Training Report
on
at
Glenmark Pharmaceuticals Ltd, Sikkim.
From 9th July to 15th July,2015
Principles and Instrumentation of Quality Control Equipments at Glenmark Pharmaceuticals Ltd., Sikkim
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Special thanks to Dr. S Roy, Head of Department
and
Mr. S.K Samanta, Asst. Professor,
Department of Biomedical Engineering,
Netaji Subhash Engineering College, Kolkata
for your constant support and inspiration.
Principles and Instrumentation of Quality Control Equipments at Glenmark Pharmaceuticals Ltd., Sikkim
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Contents
1 Analytical Balance 3
2 Autoclave 4
3 Autotitrator 6
4 BOD Incubator 7
5 Centrifuge 8
6 Conductivity meter 9
7 Disintegrator 11
8 Dissolution Tester 13
9 Gas chromatography 15
10 High Precision Liquid Chromatography 20
11 Infrared Spectroscopy 22
12 Laminar flow hood 26
13 pH meter 27
14 Refractometer 29
15 Sieve shaker 32
16 Sonicator 33
17 Tablet hardnes tester 34
18 Viscometer 35
19 Visual Melting point Apparatus 37
20 Conclusion 38
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Analytical Balance
Weighing the analytical sample is often the first step of any quantitative analytical chemical
method. To use the analytical balance effectively, the analyst must have a thorough knowledge of
the construction, design, and operation of the balance. Furthermore, the correct use and
interpretation of measurements made with the balance is dependent on an understanding of the
absolute precision with which samples can be weighed.
Working principle
The quickest way to understand the principle of how electronic balances work, is to first
understand how they are constructed. There are two basic types of electronic balance designs.
1. Electromagnetic balancing type
2. Electrical resistance wire type (load cell type)
These are based on completely different principles, but what they both have in common is
that neither directly measures mass. They measure the force that acts downward on the pan. This
force is converted to an electrical signal and displayed on a digital display.
As a means of measuring force, the electromagnetic balance method utilizes the electromagnetic
force generated from a magnet and coil, whereas the electrical resistance wire method utilizes the
change in resistance value of a strain gauge attached to a piece of metal that bends in response to
a force.
The mass is displayed because the reference standards for mass are weights, which are placed on
a pan to inform the electronic balance that a given force is equivalent to a given number of grams,
which is used for conversion. Consequently, electronic balances that do not perform this
conversion accurately cannot display accurate mass values.
Specification
Make: Sartorius
Capacity 121g
Readability 0.0001g
Maximum linearity ≤±0.0002g
Ambient temperature range +10˚C to +40˚C
Power requirements 230V, AC, 50-60Hz
Power consumption 13 VA
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Autoclave An autoclave is a device to sterilize equipment and supplies by subjecting them to high pressure saturated steam at 121 °C or more, typically for 15-20 minutes.
In its most basic form the autoclave is a pressure cooker. Water is heated in a pressurized environment to create steam. Using pressure makes it possible to heat to higher temperatures
with less energy. Autoclaves are usually made of steel and have various configurations for removing air prior to pressurization. Downward displacement autoclaves use gravity to remove
air. Steam pulsing autoclaves use pulses of steam along with pressurizing and depressurizing to reach optimum pressure. Vacuum pump autoclaves suck air out for pressurization. Super
atmospheric autoclaves are a combination of steam pulsing and vacuum pump techniques. Autoclaves are widely used in microbiology, medicine, tattooing, body piercing, veterinary science,
mycology, dentistry, chiropody and prosthetic fabrication. Typical loads include laboratory glassware, surgical instruments, medical waste, patient care
utensils, animal cage bedding, and Lysogenic broth. A notable growing application of autoclaves is in the pre-disposal treatment and sterilization of
waste material, such as pathogenic hospital waste. Machines in this category largely operate under the same principles as the original autoclave in that they are able to neutralize potentially
infectious agents by utilizing pressurized steam and superheated water.
Working
An autoclave sterilizes items by heating them with steam to a very high temperature. Some common temperatures at which autoclaves operate are: 115 degrees C/10 p.s.i., 121 degrees C/15
p.s.i., and 134 degrees C/30 p.s.i. (p.s.i.=pounds per square inch). The temperature, pressure and time of operation depend on the degree of sterilization needed.
An autoclave using standard settings can kill most bacteria, spores, viruses and fungi (all models of Osworld Autoclaves). Most doctor's offices, tattoo parlors, dentist offices and other places where
instruments might come in contact with contaminants have a small autoclave on site for disinfection (Osworld Portable Autoclave). Hospitals use larger autoclaves that look similar to
industrial dishwashers to sterilize many items at once (Rectangular/Cylindrical Horizontal Autoclave). Heat kills microorganisms by causing vital proteins to coagulate. The proteins stick
together causing fatal damage to the microorganism. An autoclave cooks microorganisms in the same way a pressure cooker cooks food, but at a higher temperature. Autoclaves use steam
instead of dry heat because steam can more effectively transmit heat to the microorganisms. It is very important to ensure that all of the trapped air is removed, as hot air is very poor at
achieving sterility. Steam at 134 °C can achieve in 3 minutes the same sterility that hot air at 160 °C takes two hours to achieve. Methods of achieving air removal include:
Downward displacement (or gravity type) - As steam enters the chamber, it fills the upper areas as
it is less dense than air. This compresses the air to the bottom, forcing it out through a drain. Often a temperature sensing device is placed in the drain. Only when air evacuation is complete
should the discharge stop. Flow is usually controlled through the use of a steam trap or a solenoid valve, but bleed holes are sometimes used, often in conjunction with a solenoid valve. As the
steam and air mix it is also possible to force out the mixture from locations in the chamber other than the bottom.
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Steam pulsing - Air dilution by using a series of steam pulses, in which the chamber is alternately
pressurized and then depressurized to near atmospheric pressure.
Vacuum pumps - Vacuum pumps to suck air or air/steam mixtures from the chamber.
Autoclave Quality Assurance
Sterilization bags/pads often have a "sterilization indicator mark" that typically darkens when the bag/pad has been processed. Comparing the mark on an unprocessed bag to a bag that has been
properly cycled will show an obvious visual difference. There are physical, chemical and biological indicators that can be used to ensure an autoclave reaches the correct temperature for the correct
amount of time.
Chemical indicators can be found on medical packaging and autoclave tape, and these change
color once the correct conditions have been met. This color change indicates that the object inside the package, or under the tape, has been processed. Some computer-controlled autoclaves use an
F0 (F-nought) value to control the sterilization cycle. F0 values are set as the number of minutes of equivalent sterilization at 121 °C (250 °F) at 15 psi (100 kPa) above atmospheric pressure for 15
minutes . Since exact temperature control is difficult, the temperature is monitored, and the sterilization time adjusted accordingly
Types of Sterilizers:
a) Clinical sterilizer: Designed to process medical devices or medicinal products
b) Laboratory Sterilizers: are designed to process laboratory goods and materials that are neither
medical devices nor medicinal products and are not intended for use in the clinical care of patients.
Specifications:
Make OSWORLD
Model OATG-175
Capacity 175L
Temperature Sensor PT-100
Pressure Range 15 to 30 psi
Temperature range 121˚C to 134˚C
Temperature resolution 0.1˚C
Temperature accuracy ±0.5˚C
Power 230V/15A/50Hz
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Autotitrator
Titrators are considered to be the perfect option used for testing of concentration that can
determine the maximum precision and productivity and find application in the field of researching
and biotechnology. These systems are also widely appreciated for their combination of simple and
dependable functioning that can be easily instrumented and designed according to the basic
routine applications. As these are microprocessor based systems, these can also be easily
accessible in operations throughout the titration process.
Specification
Make: Lab India
Model: Titra
mv Range ±3000mV
Accuracy ±0.1mV, 0.0016pH
Temperature sensors PT100
Power 230V AC±10%, 50Hz
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BOD Incubator
All the aquatic animals rely on the oxygen present in the water (dissolved oxygen) to live. Aquatic microorganisms use the organic matter discharged into the water as food source. Common natural
sources of organic matter include plant decay and leaf fall. Bacteria will break down this organic matter using the dissolved oxygen in the water and there by produce less complex organic
substances. With increased disposal of waste materials (including organic compounds), the utility of dissolved oxygen by the microorganisms will also increased. So the water becomes depleted in
oxygen. In this anaerobic condition, microorganisms will produce offensive products and may result in undesirable effects like fish asphyxiation. So the amount of dissolved oxygen in the water
is an indicator of the quality of water.
Biological oxygen demand is a widely used technique to express the concentration of organic matter in waste water samples. It is a measure of the amount of dissolved oxygen used by
microorganisms in the water. If the amount of organic matter in sewage is more, the more oxygen will be utilized by microorganisms to degrade dumping sewage which containing high BOD value.
Digestion of these organic compounds in neutral ecosystem such as lakes, rivers etc. can deplete available oxygen and result in fish asphyxiation.
The BOD of a water sample is generally measured by incubating the sample at 20oC for 5 days in
the dark room under aerobic condition (in BOD incubator). In the water samples where more than 70% of initial oxygen is consumed, it is necessary to aerate or oxygenate and dilute the sample
with BOD free water (de ionized glass distilled water) pass through a column of activated carbon and redistilled to avoid O2 stress.
Working Principle Under alkaline conditions (by adding Alkaline-iodide-azide), the manganese sulphate produces a
white precipitate of manganese hydroxide. This reacts with the dissolved oxygen present in the sample to form a brown precipitate. On acidic condition, manganese diverts to its divalent state
and release iodine. This released iodine is titrated against Sodium thiosulphate using starch as an indicator.
Specifications
Make: Newtronic
Model:NW-480
Temperature range +5˚C to 60˚C
Temperature accuracy ±0.5˚C
Temperature uniformity ±1˚C
Temperature sensor PT-100
Power supply 230V,50Hz mains
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Centrifuge
Centrifuge is applying centrifugal force to separate the useful component in mixtures of liquids
and solids or liquids and liquids. Centrifuge is mainly used to separate solids from liquids in
suspension or separate two liquids with different density and non-homogenous liquids, for
example, separate cream form milk; and also it can be used to remove liquids existed in solids,
such as special speeding tubular centrifuges can separate the mixed gas content with different
density, depending different density and particle size of solid particles in the liquid and different
characteristics of the subsiding speed centrifuge, the sedimentation centrifuge also can classified
solids according to different density and particle size. Centrifuge is widely used in chemical, oil,
food, pharmaceutical, beneficiation, coal, water treatment and shipping etc. Part Centrifuge has a
drum rotating its axle called bowl, generally drived by motor. Suspension or emulsion is
introduced to the bowl and rotate with bowl with the same speed, eject separately under the
centrifugal force.Usually,high separation speed, high separation ratio. The principle of centrifuge is
divided to centrifugal filtering and centrifugal sedimentation. Centrifugal filtering is made
suspension become filtrate under the centrifugal force and the centrifugal sedimentation is
applied different density to separate suspension and emulsion and realize liquid-solid or liquid-
liquid separation.
Specification
Make: Remi
Model: R-4C
Maximum speed 4200 rpm
Maximum RCF 3150 g
Maximum capacity 200 ml
Power Supply 220-240 V, 50 Hz, AC
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Conductivity meter
Conductivity measurement is an extremely widespread and useful method, especially for quality
control purposes. Surveillance of feed water purity, control of drinking water and process water
quality, estimation of the total number of ions in a solution or direct measurement of components
in process solutions can all be performed using conductivity measurements. The high reliability,
sensitivity and relatively low cost of conductivity instrumentation makes it a potential primary
parameter of any good monitoring program. Some applications are measured in units of
resistivity, the inverse of conductivity. Other applications require the measurement of total
dissolved solids (TDS), which is related to conductivity by a factor dependent upon the level and
type of ions present. Conductivity measurements cover a wide range of solution conductivity from
pure water at less than 1x10-7 S/cm to values of greater than 1 S/cm for concentrated solutions. In
general, the measurement of conductivity is a rapid and inexpensive way of determining the ionic
strength of a solution. However, it is a nonspecific technique, unable to distinguish between
different types of ions, giving instead a reading that is proportional to the combined effect of all
the ions present.
Working
A typical conductivity meter applies an alternating current (I) at an optimal frequency1) to two active
electrodes and measures the potential (V). Both the current and the potential are used to calculate the
conductance (I/V). The conductivity meter then uses the conductance and cell constant to display the
conductivity. Conductivity2) = cell constant x conductance Note: the current source is adjusted so that the
measured potential (V) is equal to the reference potential (Er) (approximately ± 200 mV).
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Conductivity cells 2-pole cell In a traditional 2-pole cell, an alternating current is applied between
the 2 poles and the resulting voltage is measured. The aim is to measure the solution resistance
(Rsol) only. However the resistance (Rel) caused by polarization of the electrodes and the field
effect interferes with the measurement, and both Rsol and Rel are measured. Methods of
reducing the effects of polarization are explained on page 16. Rel Rel Electrical current V Rsol I Fig.
3: Simplified diagram of a 2-pole conductivity cell 3-pole cell The 3-pole cell is not as popular now
as it has been replaced by the 4-pole one. The advantage of this design was that the third pole
which was linked to pole 1 allowed the field lines to be guided and confined in an optimal manner,
limiting dispersion in the measurement and minimizing influences on the measurement such as
beaker volume and position of the cell in the beaker (field effect). It guarantees a better
reproducibility when determining the cell constant and therefore more reproducible results. - 12 -
4-pole cell In a 4-pole cell, a current is applied to the outer rings (1 and 4) in such a way that a
constant potential difference is maintained between the inner rings (2 and 3). As this voltage
measurement takes place with a negligible current, these two electrodes are not polarized (R2 =
R3 = 0). The conductivity will be directly proportional to the applied current. The geometry of 4-
pole cells with an outer tube minimizes the beaker field effect, due to the measurement volume
being well defined within the tube. The position of the conductivity cell in the measuring vessel or
the sample volume therefore has no influence on the measurement.
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Disintegrator
An orally administered drug must disintegrate to attain good absorption of its active substance.
The first step toward dissolution is usually the break-up of the tablet; a process described as
disintegration. The disintegration test results in a time necessary to disintegrate a group of tablets
into small particles under standard conditions. The disintegration test is a valuable tool in quality
control environments. The test is used for batch release and trending of lot-to-lot variations during
manufacturing of tablets.
The disintegration test determines whether tablets or capsules disintegrate within the prescribed
time when placed in a liquid medium in the experimental conditions prescribed below.
Disintegration is considered to be achieved when: a) no residue remains on the screen, or b) if
there is a residue, it consists of a soft mass having no palpably firm, unmoistened core, or c) only
fragments of coating (tablets) or only fragments of shell (capsules) remain on the screen; if a disc
has been used (capsules), fragments of shell may adhere to the lower surface of the disc.
Specifications
Device: Tablet Disintegrator Tester
Make & Model: Electro lab, ED-2SAPO
Salient Features:
Disintegration time registration of each tablet
Built-in stirrer for precise temperature probes for continuous monitoring of temperature in
both the beakers.
Power failure recovery.
Parts Specifications
Motor Stepper motor (2nos.)
Display 20x4 LCD
Heater 230V AC, 400W
Illumination White LED
Power Supply 230V AC, 50/60 Hz
Stroke rate 30±1 stroke/minute
Stroke height 55mm±2mm
Temperature 30.0˚C to 40.0˚C
Temperature accuracy ±0.2 ˚C
Resolution 0.1 ˚C
Power 220/230V AC,50Hz,500W
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Operation
The operation of disintegrator is quite simple, with a
electronic Resistor-Capacitor (RC) circuit controlling the
timer settings and a temperature sensor (for example,
AD590) constantly monitoring the water bath
temperature and completing a feedback circuit. The
purpose of the feedback circuit is maintenance of the
temperature within the prescribed range.
There are two stepper motors which is electronically
connected to the overall circuitry and controls the
vertical movement of the basket rack assembly during
device operation. A Stepper Motor or a step motor is a
brushless, synchronous motor which divides a full
rotation into a number of steps. Unlike a brushless DC
motor which rotates continuously when a fixed DC
voltage is applied to it, a step motor rotates in discrete
step angles. The Stepper Motors therefore are manufactured with steps per revolution of 12, 24,
72, 144, 180, and 200, resulting in stepping angles of 30, 15, 5, 2.5, 2, and 1.8 degrees per step.
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Dissolution Test
Tablets or capsules taken orally remain one of the most
effective means of treatment available. The effectiveness of
such dosage forms relies on the drug dissolving in the fluids of
the gastrointestinal tract prior to absorption into the systemic
circulation. The rate of dissolution of the tablet or capsule is
therefore crucial. One of the problems facing the
pharmaceutical industry is to optimize the amount of drug
available to the body, i.e. its bioavailability. Inadequacies in
bioavailability can mean that the treatment is ineffective and
at worst potentially dangerous (toxic overdose). Drug release
in the human body can be measured in-vivo by measuring the
plasma or urine concentrations in the subject concerned.
However, there are certain obvious impracticalities involved in
employing such techniques on a routine basis. These
difficulties have led to the introduction of official in-vitro tests
which are now rigorously and comprehensively defined in the
respective Pharmacopoeia.
Tablet Dissolution is a standardized method for measuring the
rate of drug release from a dosage form. The principle function of the dissolution test may be
summarized as follows:
Optimization of therapeutic effectiveness during product development and stability assessment.
Routine assessment of production quality to ensure uniformity between production lots.
Assessment of ‘bioequivalence’, that is to say, production of the same biological availability from
discrete batches of products from one or different manufacturers. Prediction of in-vivo availability,
i.e. bioavailability (where applicable). Although initially developed for oral dosage forms, the role
of the dissolution test has now been extended to drug release studies on various other forms such
as topical and transdermal systems and suppositories.
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Specifications
Device: Dissolution System
Make & Model: Electro lab, EDT-14Lx
Salient features:
Magnetically coupled water circulating pump for precise temperature control of the water
bath
Individual vessel centering system
Component Specification
No. of stations 12
Speed range 20 to 250 RPM
Speed accuracy 0.5 RPM
Temperature Range 20˚C to 40˚C
Temperature Accuracy 0.1˚C
Display 40x4 LCD
Stirrer drive High performance BLDC
Temperature controller Heater:1kW, SS 316 Sensor: RTD Circulation: Magnetically coupled
Power 220/230V AC, 50/60Hz
Operation
The input such as RPM, dissolution time,temperature,ect is taken from the user and processed
through suitable electronic circuitry and is fed to the respect control unit. There are mainly two
main control unit circuitry, that is temperature control and RPM control. The former parameter,
temperature is sensed using an Resistor Temperature Detector and the later parameter is
controlled by using Brush Less DC (BLDC) motor.
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GAS Chromatography
Gas chromatography is a term used to describe the group of analytical separation techniques used
to analyze volatile substances in the gas phase. In gas chromatography, the components of a
sample are dissolved in a solvent and vaporized in order to separate the analytes by distributing
the sample between two phases: a stationary phase and a mobile phase. The mobile phase is a
chemically inert gas that serves to carry the molecules of the analyte through the heated column.
Gas chromatography is one of the sole forms of chromatography that does not utilize the mobile
phase for interacting with the analyte. The stationary phase is either a solid adsorbent, termed
gas-solid chromatography (GSC), or a liquid on an inert support, termed gas-liquid
chromatography (GLC).
Instrumentation
Sample Injection: A sample port is necessary for
introducing the sample at the head of the column.
Modern injection techniques often employ the use of
heated sample ports through which the sample can be
injected and vaporized in a near simultaneous fashion.
A calibrated micro syringe is used to deliver a sample
volume in the range of a few microliters through a
rubber septum and into the vaporization chamber.
Most separations require only a small fraction of the
initial sample volume and a sample splitter is used to
direct excess sample to waste.
The vaporization chamber is typically heated 50 °C
above the lowest boiling point of the sample and
subsequently mixed with the carrier gas to transport the
sample into the column.
Carrier Gas: The carrier gas plays an important role, and
varies in the GC used. Carrier gas must be dry, free of
oxygen and chemically inert mobile-phase employed in gas chromatography. Helium is most
commonly used because it is safer than, but comparable to hydrogen in efficiency, has a larger
range of flow rates and is compatible with many detectors. Nitrogen, argon, and hydrogen are
also used depending upon the desired performance and the detector being used. Both hydrogen
and helium, which are commonly used on most traditional detectors such as Flame Ionization(FID),
thermal conductivity (TCD) and Electron capture (ECD), provide a shorter analysis time and lower
elution temperatures of the sample due to higher flow rates and low molecular weight. For
instance, hydrogen or helium as the carrier gas gives the highest sensitivity with TCD because the
difference in thermal conductivity between the organic vapor and hydrogen/helium is greater
than other carrier gas. Other detectors such as mass spectroscopy, uses nitrogen or argon which
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has a much better advantage than hydrogen or helium due to their higher molecular weights, in
which improve vacuum pump efficiency. All carrier gasses are available in pressurized tanks and pressure regulators, gages and flow meters
are used to meticulously control the flow rate of the gas. Most gas supplies used should fall
between 99.995% - 99.9995% purity range and contain a low levels (< 0.5 ppm) of oxygen and
total hydrocarbons in the tank. The carrier gas system contains a molecular sieve to remove water
and other impurities. Traps are another option to keep the system pure and optimum sensitive
and removal traces of water and other contaminants. A two stage pressure regulation is required
to use to minimize the pressure surges and to monitor the flow rate of the gas. To monitor the
flow rate of the gas a flow or pressure regulator was also require onto both tank and
chromatograph gas inlet. This applies different gas type will use different type of regulator. The
carrier gas is preheated and filtered with a molecular sieve to remove impurities and water prior
to being introduced to the vaporization chamber.
Column Oven: The thermostatted oven serves to control the temperature of the column within a
few tenths of a degree to conduct precise work. The oven can be operated in two
manners: isothermal programming or temperature programming. In isothermal programming, the
temperature of the column is held constant throughout the entire separation. However,
isothermal programming works best only if the boiling point range of the sample is narrow. If a
low isothermal column temperature is used with a wide boiling point range, the low boiling
fractions are well resolved but the high boiling fractions are slow to elute with extensive band
broadening. If the temperature is increased closer to the boiling points of the higher boiling
components, the higher boiling components elute as sharp peaks but the lower boiling
components elute so quickly there is no separation. In the temperature programming method, the column temperature is either increased continuously or in steps as the separation progresses. This method is well suited to separating a mixture with a broad boiling point range. This method is well suited to separating a mixture with a broad boiling point range. The analysis begins at a low temperature to resolve the low boiling components and increases during the separation to resolve the less volatile, high boiling components of the sample. Rates of 5-7 °C/minute are typical for temperature programming separations.
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Open Tubular Columns and Packed Columns: Open tubular columns, which are also known as
capillary columns, come in two basic forms. The first is a wall-coated open tubular (WCOT) column
and the second type is a support-coated open tubular (SCOT) column. WCOT columns are capillary
tubes that have a thin later of the stationary phase coated along the column walls. In SCOT
columns, the column walls are first coated with a thin layer (about 30 micrometers thick) of
adsorbent solid, such as diatomaceous earth, a material which consists of single-celled, sea-plant
skeletons. The adsorbent solid is then treated with the liquid stationary phase. While SCOT
columns are capable of holding a greater volume of stationary phase than a WCOT column due to
its greater sample capacity, WCOT columns still have greater column efficiencies.
Most modern WCOT columns are made of glass, but T316 stainless steel, aluminum, copper and
plastics have also been used. Each material has its own relative merits depending upon the
application. Glass WCOT columns have the distinct advantage of chemical etching, which is usually
achieved by gaseous or concentrated hydrochloric acid treatment. The etching process gives the
glass a rough surface and allows the bonded stationary phase to adhere more tightly to the
column surface.
Detection Systems: The detector is the device located at the end of the column which provides a
quantitative measurement of the components of the mixture as they elute in combination with
the carrier gas. In theory, any property of the gaseous mixture that is different from the carrier
gas can be used as a detection method. These detection properties fall into two categories: bulk
properties and specific properties. Bulk properties, which are also known as general properties,
are properties that both the carrier gas and analyte possess but to different degrees. Specific
properties, such as detectors that measure nitrogen-phosphorous content, have limited
applications but compensate for this by their increased sensitivity.
Each detector has two main parts that when used together they serve as transducers to
convert the detected property changes into an electrical signal that is recorded as a
chromatogram. The first part of the detector is the sensor which is placed as close the the column
exit as possible in order to optimize detection. The second is the electronic equipment used to
digitize the analog signal so that a computer may analyze the acquired chromatogram. The sooner
the analog signal is converted into a digital signal, the greater the signal-to-noise ratio becomes, as
analog signal are easily susceptible to many types of interferences.
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Mass Spectrometry Detectors: Mass Spectrometer (MS) detectors are most powerful of all gas chromatography detectors. In a GC/MS system, the mass spectrometer scans the masses continuously throughout the separation. When the sample exits the chromatography column, it is passed through a transfer line into the inlet of the mass spectrometer . The sample is then ionized and fragmented, typically by an electron-impact ion source. During this process, the sample is bombarded by energetic electrons which ionize the molecule by causing them to lose an electron due to electrostatic repulsion. Further bombardment causes the ions to fragment. The ions are then passed into a mass analyzer where the ions are sorted according to their m/z value, or mass-to-charge ratio. Most ions are only singly charged.
The Chromatogram will point out the retention times and the mass spectrometer will use the peaks to determine what kind of molecules are exist in the mixture. The figure below represents a typical mass spectrum of water with the absorption peaks at the appropriate m/z ratios. Electron-capture Detectors: Electron-capture detectors (ECD) are highly selective detectors commonly used for detecting environmental samples as the device selectively detects organic compounds with moieties such as halogens, peroxides, quinones and nitro groups and gives little to no response for all other compounds. Therefore, this method is best suited in applications where traces quantities of chemicals such as pesticides are to be detected and other chromatographic methods are unfeasible.
The simplest form of ECD involves gaseous electrons from a radioactive ? emitter in an electric field. As the analyte leaves the GC column, it is passed over this ? emitter, which typically consists of nickle-63 or tritium. The electrons from the ? emitter ionize the nitrogen carrier gas and cause it to release a burst of electrons. In the absence of organic compounds, a constant standing current is maintained between two electrodes. With the addition of organic compounds with electronegative functional groups, the current decreases significantly as the functional groups capture the electrons.
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The advantages of ECDs are the high selectivity and sensitivity towards certain organic species with electronegative functional groups. However, the detector has a limited signal range and is potentially dangerous owing to its radioactivity. In addition, the signal-to-noise ratio is limited by radioactive decay and the presence of O2 within the detector.
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High Performance Liquid Chromatography In chromatography a liquid is pumped through a bed of particles. The liquid is called the mobile phase and the particles the stationary phase. A mixture of the molecules that shall be separated is introduced into the mobile phase. The molecules in the mixture that adsorbs the most to the stationary phase, in this particular case the red molecules, is moving slowest through the particle bed. The red molecules become separated from the blue!
Working
The heart of a HPLC system is the column. The column contains the particles that contains the stationary phase. The mobile phase is pumped through the column by a pump. The mixture to be separated is injected into the flowing mobile phase by an injector. In the animation below the injector injects a mixture of blue and red molecules into the mobile phase. When the mobile phase passes through the column that contains the stationary phase, the molecules that adsorbs most to the stationary phase migrates slowest through the column. When the mobile phase has passed through the column it enters into the detector that detects the different molecules as they have pass through it. A signal goes from the detector to a printer that presents the separation graphically.
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Specification
Make: Shimazdu
Model:LC-2010 CHT
Pump type Serial dual pluger, micro volume
Flow rate 0.001-5mL/min
Flow rate accuracy ±1% or ±2uL/min
Pressure display accuracy ±2% or ±0.5Mpa
Concentration precision ±0.1%
Column Oven Block heating
Temperature setting range 4-60˚C
UV source Deuterium lamp
Wavelength range 190-600nm
Power 100-240V AC, 700VA, 50/60 Hz
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Infrared Spectroscopy
Infrared spectroscopy has been a workhorse technique for materials analysis in the laboratory for over seventy years. An infrared spectrum represents a fingerprint of a sample with absorption peaks which correspond to the frequencies of vibrations between the bonds of the atoms making up the material. Because each different material is a unique combination of atoms, no two compounds produce the exact same infrared spectrum. Therefore, infrared spectroscopy can result in a positive identification (qualitative analysis) of every different kind of material. In addition, the size of the peaks in the spectrum is a direct indication of the amount of material present. With modern software algorithms, infrared is an excellent tool for quantitative analysis. In infrared spectroscopy, IR radiation is passed through a sample. Some of the infrared radiation is absorbed by the sample and some of it is passed through (transmitted). The resulting spectrum represents the molecular absorption and transmission, creating a molecular fingerprint of the sample. Like a fingerprint no two unique molecular structures produce the same infrared spectrum. This makes infrared spectroscopy useful for several types of analysis.
Fourier Transform Infrared Spectroscopy (FTIR)
Fourier Transform Infrared (FT-IR) spectrometry was developed in order to overcome the limitations encountered with dispersive instruments. The main difficulty was the slow scanning process. A method for measuring all of the infrared frequencies simultaneously, rather than individually, was needed. A solution was developed which employed a very simple optical device called an interferometer. The interferometer produces a unique type of signal which has all of the infrared frequencies “encoded” into it. The signal can be measured very quickly, usually on the order of one second or so. Thus, the time element per sample is reduced to a matter of a few seconds rather than several minutes. Most interferometers employ a beam splitter which takes the incoming infrared beam and divides it into two optical beams. One beam reflects off of a flat mirror which is fixed in place. The other beam reflects off of a flat mirror which is on a mechanism which allows this mirror to move a very short distance (typically a few millimeters) away from the beam splitter. The two beams reflect off of their respective mirrors and are recombined when they meet back at the beam splitter. Because the path that one beam travels is a fixed length and the other is constantly changing as its mirror moves, the signal which exits the interferometer is the result of these two beams “interfering” with each other. The resulting signal is called an interferogram which has the unique property that every data point (a function of the moving mirror position) which makes up the signal has information about every infrared frequency which comes from the source. This means that as the interferogram is measured, all frequencies are being measured simultaneously. Thus, the use of the interferometer results in extremely fast measurements. Because the analyst requires a frequency spectrum (a plot of the intensity at each individual frequency) in order to make an identification, the measured interferogram signal can not be interpreted directly. A means of “decoding” the individual frequencies is required. This can be accomplished via a well-known mathematical technique called the Fourier transformation. This transformation is performed by the computer which then presents the user with the desired spectral information for analysis.
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FTIR has a numerous practical applications such as it can identify unknown materials, can determine the quality or consistency of a sample or can determine the amount of components in a mixture. Instrumentation The normal instrumental process is as follows: 1. The Source: Infrared energy is emitted from a glowing black-body source. This beam passes through an aperture which controls the amount of energy presented to the sample (and, ultimately, to the detector). 2. The Interferometer: The beam enters the interferometer where the “spectral encoding” takes place. The resulting interferogram signal then exits the interferometer. 3. The Sample: The beam enters the sample compartment where it is transmitted through or reflected off of the surface of the sample, depending on the type of analysis being accomplished. This is where specific frequencies of energy, which are uniquely characteristic of the sample, are absorbed. 4. The Detector: The beam finally passes to the detector for final measurement. The detectors used are specially designed to measure the special interferogram signal. 5. The Computer: The measured signal is digitized and sent to the computer where the Fourier transformation takes place. The final infrared spectrum is then presented to the user for interpretation and any further manipulation.
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Because there needs to be a relative scale for the absorption intensity, a background spectrum must also be measured. This is normally a measurement with no sample in the beam. This can be compared to the measurement with the sample in the beam to determine the “percent transmittance.” This technique results in a spectrum which has all of the instrumental characteristics removed. Thus, all spectral features which are present are strictly due to the sample. A single background measurement can be used for many sample measurements because this spectrum is characteristic of the instrument itself.
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FTIR v/s IR
The original infrared instruments were of the dispersive type. These instruments separated the individual frequencies of energy emitted from the infrared source. This was accomplished by the use of a prism or grating. An infrared prism works exactly the same as a visible prism which separates visible light into its colors (frequencies). A grating is a more modern dispersive element which better separates the frequencies of infrared energy. The detector measures the amount of energy at each frequency which has passed through the sample. This results in a spectrum which is a plot of intensity vs. frequency. Fourier transform infrared spectroscopy is preferred over dispersive or filter methods of infrared spectral analysis for several reasons: • It is a non-destructive technique • It provides a precise measurement method which requires no external calibration • It can increase speed, collecting a scan every second • It can increase sensitivity – one second scans can be co-added together to ratio out random noise • It has greater optical throughput • It is mechanically simple with only one moving part
Advantages of FT-IR Some of the major advantages of FT-IR over the dispersive technique include: • Speed: Because all of the frequencies are measured simultaneously, most measurements by FTIR are made in a matter of seconds rather than several minutes. This is sometimes referred to as the Felgett Advantage. • Sensitivity: Sensitivity is dramatically improved with FT-IR for many reasons. The detectors employed are much more sensitive, the optical throughput is much higher (referred to as the Jacquinot Advantage) which results in much lower noise levels, and the fast scans enable the condition of several scans in order to reduce the random measurement noise to any desired level (referred to as signal averaging). • Mechanical Simplicity: The moving mirror in the interferometer is the only continuously moving part in the instrument. Thus, there is very little possibility of mechanical breakdown. • Internally Calibrated: These instruments employ a HeNe laser as an internal wavelength calibration standard (referred to as the Connes Advantage). These instruments are self-calibrating and never need to be calibrated by the user. These advantages, along with several others, make measurements made by FT-IR extremely accurate and reproducible. Thus, it a very reliable technique for positive identification of virtually any sample. The sensitivity benefits enable identification of even the smallest of contaminants. This makes FT-IR an invaluable tool for quality control or quality assurance applications whether it be batch-to-batch comparisons to quality standards or analysis of an unknown contaminant. In addition, the sensitivity and accuracy of FT-IR detectors, along with a wide variety of software algorithms, have dramatically increased the practical use of infrared for quantitative analysis. Quantitative methods can be easily developed and calibrated and can be incorporated into simple procedures for routine analysis.
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Laminar Flow Hoods (LFH)
A laminar flow hood is a carefully enclosed bench designed to prevent contamination of
semiconductor wafers, biological samples, or any particle sensitive materials. Air is drawn through a HEPA filter and blown in a very smooth, laminar flow towards the user. The cabinet is usually
made of stainless steel with no gaps or joints where spores might collect.
Working Principle A laminar flow hood consists of a filter pad, a fan and a HEPA (High Efficiency Particulates Air)
filter. The fan sucks the air through the filter pad where dust is trapped. After that the prefiltered air has to pass the HEPA filter where contaminating fungi, bacteria, dust etc. are removed. Now
the sterile air flows into the working (flasking) area where the user can do all his/her flasking work without risk of contamination.
The Laminar Flow Hoods (LFH) provides clean air to the working area and a constant flow of air out of the work area to prevent room air from entering the working area. The air flowing out from
the hood suspends and removes contaminants introduced into the work area by personnel.
The most important part of a laminar flow hood is a high efficiency bacteria-retentive filter. Room air is taken into the unit and passed through a pre-filter to remove gross contaminants (lint, dust
etc.). The air is then compressed and channeled up behind and through the HEPA filter (High Efficiency Particulate Air filter) in a laminar flow fashion--that is the purified air flows out over the
entire work surface in parallel lines at a uniform velocity. The HEPA filter removes nearly all of the bacteria from the air.
Such hoods exist in both horizontal and vertical configurations, and there are many different types of cabinets with a variety of airflow patterns and acceptable uses.
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pH meter
An acidic solution has far more positively charged hydrogen ions in it than an alkaline one, so it has
greater potential to produce an electric current in a certain situation—in other words, it's a bit like
a battery that can produce a greater voltage. A pH meter takes advantage of this and works like
a voltmeter: it measures the voltage (electrical potential) produced by the solution whose acidity
we're interested in, compares it with the voltage of a known solution, and uses the difference in
voltage (the "potential difference") between them to deduce the difference in pH.
Instrumentation:
A typical pH meter has two basic components: the meter itself, which can be a moving-coil
meter (one with a pointer that moves against a scale) or a digital meter (one with a numeric
display), and either one or two probes that you insert into the solution you're testing. To make
electricity flow through something, you have to create a complete electrical circuit; so, to make
electricity flow through the test solution, you have to put two electrodes (electrical terminals) into
it. If your pH meter has two probes (like the one in the photo at the top of this article), each one is
a separate electrode; if you have only one probe, both of the two electrodes are built inside it for
simplicity and convenience.
The electrodes aren't like normal electrodes (simple pieces of metal wire); each one is a mini
chemical set in its own right. The electrode that does the most important job, which is called
the glass electrode, has a silver-based electrical wire suspended in a solution of potassium
chloride, contained inside a thin bulb (or membrane) made from a special glass containing metal
salts (typically compounds of sodium and calcium). The other electrode is called the reference
electrode and has a potassium chloride wire suspended in a solution of potassium chloride.
Working
The potassium chloride inside the glass electrode (shown here colored orange) is a neutral
solution with a pH of 7, so it contains a certain amount of hydrogen ions (H+). Suppose the
unknown solution you're testing (blue) is much more acidic, so it contains a lot more hydrogen
ions. What the glass electrode does is to measure the difference in pH between the orange
solution and the blue solution by measuring the difference in the voltages their hydrogen ions
produce. Since we know the pH of the orange solution (7), we can figure out the pH of the blue
solution. When we dip the two electrodes into the blue test solution, some of the hydrogen ions
move toward the outer surface of the glass electrode and replace some of the metal ions inside it,
while some of the metal ions move from the glass electrode into the blue solution. This ion-
swapping process is called ion exchange, and it's the key to how a glass electrode works. Ion-
swapping also takes place on the inside surface of the glass electrode from the orange solution.
The two solutions on either side of the glass have different acidity, so a different amount of ion-
swapping takes place on the two sides of the glass. This creates a different degree of hydrogen-ion
activity on the two surfaces of the glass, which means a different amount of electrical charge
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builds up on them. This charge difference means a tiny voltage (sometimes called a potential
difference, typically a few tens or hundreds of millivolts) appears between the two sides of the
glass, which produces a difference in voltage between the silver electrode (5) and the reference
electrode (8) that shows up as a measurement on the meter.
Although the meter is measuring voltage, what the pointer on the scale (or digital display) actually
shows us is a pH measurement. The bigger the difference in voltage between the orange (inside)
and blue (outside) solutions, the bigger the difference in hydrogen ion activity between. If there is
more hydrogen ion activity in the blue solution, it's more acidic than the orange solution and the
meter shows this as a lower pH; in the same way, if there's less hydrogen ion activity in the blue
solution, the meter shows this as a higher pH (more alkaline).
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Refractometer
A refractometer is a laboratory or field device for the measurement of an index of
refraction (refractometry). The index of refraction is calculated from Snell's law and can be calculated from the composition of the material using the Gladstone–Dale relation.
Working Principle
When light enters from a medium with a lower refractive index as for example air into a medium
with a higher refractive index as for example water it thus changes its speed. This has as a consequence that a beam of light changes its angle when it passes from one medium with a
refractive index n1 to another medium with a refractive index n2.The ratio of the sines of the two angles is equivalent to the opposite ratio of the refractive indices of the two media. This
mathematical relationship is known as Snell's law.
The refractive index depends on the temperature of the media: The higher the temperature of a media, the higher the speed of light in the media and the lower its refractive index. The picture
below shows the refractive index of water in relation to the temperature. In vacuum light travels at a constant speed (c), independent of its wavelength. In all other media, however, the speed of
light depends as well on its wavelength: The shorter the wavelength of the light, the higher its speed. This frequency dependency of the refractive index is known as dispersion and causes a
prism or a rainbow (where the light travels from air through water) to divide white light into its constituent spectral colors.
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The refractive index has thus always to be stated together with the wavelength of the light used for the measurement and the temperature of the media. The refractive index is normally
measured at a temperature of 20°C using light with the wavelength of the sodium D line (589.29 nm) and is therefore expressed as nD20.
In digital refractometers the light (1) travels from a prism (2) with a high refractive index (normally glass or artificial sapphire) into the sample (3). If the angle of incidence exceeds a certain value,
the light is reflected at the prism/sample boundary (see 'total internal reflection' in the chapter above). The reflected light is detected by a CCD (or CMOS) sensor (4): The lower the refractive
index of the sample being measured, the smaller the critical angle and the bigger the illuminated surface of the sensor. The refractive index of the sample can thus by calculated by the
refractometer, using the ratio of the length of the illuminated and the length of the dark region on the CCD.
Under ideal conditions a sharp transition dividing the dark and the light areas is yielded on the CCD.
When measuring turbid samples, however, part of the light is reflected by the particles in the sample.
The same can happen if the prism of the instrument was not clean when the sample was applied (non
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homogeneous sample on the surface of the prism) or if too few sample was used for the
measurement (total reflection of light at the interface sample/air!). A part of this so called scattered light hits the CCD as well causing a blurry transition dividing the dark and the light areas
on the CCD. Scattered light reduces the accuracy of the reading and is one of the most frequent sources of error when performing refractive index measurements. The pictures below illustrate
the measurement of a clear (no scattered light, left) and a turbid (scattered light, right) sample.
When measuring turbid samples with optical Abbe refractometers, this blurry transition can easily
been seen. With most digital refractometers, however, this is not the case: They simply give a non accurate reading.
Applications
The refractive index is a value specific to a material. It is therefore a quick and easy method for materials characterization and to check the purity of liquids.
Often the refractive index is used for concentration determinations in binary mixtures. The most
popular concentration measurement by refractive index is the determination of the sugar concentration in water. There are many refractometers which directly display the results in so
called Brix degrees: One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the concentration of the solution as percentage by weight (% w/w). Such instruments are mainly
popular in the food industry. The BX-1 portable digital Brix Meter from KEM is a very easy to use instrument for this application.
The RA-600 and RA-610 refractometers from KEM are ideally suited for concentration measurements: They have several built-in concentration scales and can store up to 100 additional
concentration tables. With these instruments it is thus possible to cover a wide range of different concentration determinations by refractive index.
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Sieve shaker
A sieve shaker is a machine designed to hold and agitate a stack of sieves for the purpose of
separating a soil or other granular material sample into its component particles by size. The stack
of sieves is composed of sieves of different sizes. The one with the largest openings is on the top
while the sieve with the smallest openings is on the bottom with a solid tray beneath to catch the
smallest of the particles. The sample is placed into the top sieve of the stack, and as the sieve
shaker agitates the sample, the individual components sift through each of the sieves in turn with
each one retaining particles of a successively smaller size.
Agitation patterns can vary from machine to another. Some sieve shakers use a circular motion, moving the sieves in a circle but without rotating them. Vibration is another method and a third method incorporates a vertical element with a lateral shaking movement like a chef tossing food in a frying pan. Some sieve shaker machines are capable of more than one of these patterns.
All sieve machines have electric motors. Some models are portable, running on battery power. Controls tend to be relatively simple and include timers and shaker motion controls. Most sieve shakers accept any manufacturer's sieve although some can use only their own sieves.
Specification Make: Electro Lab Model: EMS-8
Noise level up to 70dB
Power 230 VAC, 2A, 50-60Hz
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Sonicator
Sonication is the act of applying sound energy to agitate particles in a sample, for various
purposes. Ultrasonic frequencies (>20 kHz) are usually used, leading to the process also being
known as ultra sonication or ultra-sonication.
In the laboratory, it is usually applied using an ultrasonic bath or an ultrasonic probe, colloquially
known as a sonicator.
Sonication can be used to speed dissolution, by breaking intermolecular interactions. It is
especially useful when it is not possible to stir the sample, as with NMR tubes. It may also be used to provide the energy for certain chemical reactions to proceed. Sonication can be used to remove
dissolved gases from liquids (degassing) by sonicating the liquid while it is under a vacuum. This is an alternative to the freeze-pump-thaw and sparging methods.
Working principle High frequency electrical energy is converted into ultrasound waves by means of ultrasonic transducers, which are bonded to the base of a Stainless Steel Water Tank. These high frequency
sound waves create in the liquid countless, microscopic vacuum bubbles, which rapidly expand and collapse. This phenomenon is called cavitation. These bubbles act like miniature high speed
brushes, driving the liquid into all the openings and minute recesses of the object immersed in the liquid. Intense scrubbing by the process of cavitation cleans away all the dirt and soil from the
object immersed and the object comes out perfectly cleaned. Intricate objects can be cleaned with either complete or little dismantling.
Applications
Laboratory: for glassware, filter cleaning & HPLC mobile phase, degassing Industrial: semi-conductors, electronic components, precious parts & mechanisms Medical: dental & surgical instruments Optical: glasses, glasses frames, lenses Jewelry: for all kinds of jewelry, precious stones, etc. Removes: dust, oils, grease, polishing compounds, waxes, stains, soils, and any other
contaminant
Specifications
Operating frequency 33±3 KHz
Power 170V-270V AC, 50Hz
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Tablet Hardness Tester
Tablet hardness testing, is a laboratory technique used by the pharmaceutical industry to test the
breaking point and structural integrity of a tablet "under conditions of storage, transportation, and
handling before usage" The breaking point of a tablet is based on its shape. It is similar
to friability testing, but they are not the same thing. There are 2 main processes to test tablet
hardness: compression testing and 3 point bend testing. For compression testing, the analyst
generally aligns the tablet in a repeatable way, and the tablet is squeezed by 2 jaws. The first
machines continually applied force with a spring and screw thread until the tablet started to
break. When the tablet fractured, the hardness was read with a sliding scale.
Specification
Make:Erweka
Diameter measurement 2-28mm
Thickness measurement 0.10-28mm
Accuracy ±0.05mm
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Viscometer
A rotational viscometer consists of a sample-filled cup and a measuring bob that is immersed into
the sample. There are two main principles in use:
The Couette Principle
The Searle Principle
The Couette principle - bob fixed, cup rotates. If the bob stands still and the drive rotates the
sample cup, this is the Couette principle (named after M. M. A. Couette, 1858 to 1943). Although
this construction avoids problems with turbulent flow, it is rarely used in commercially available
instruments. This is probably due to problems with the insulation and tightness of the rotating
sample cup.
The Searle Principle: In most industrially available viscometers the motor drives the measuring bob
and the sample cup stands still. The viscosity is proportional to the motor torque that is required
for turning the measuring bob against the fluid’s viscous forces. This is called the Searle principle
(named after G. F. C. Searle, 1864 to 1954). When employing the Searle principle, the bob's
rotational speed in low-viscosity samples should not be too high. Otherwise flow could occur due
to centrifugal forces or the effects of inertia.
Physics of the Searle Principle
The motor turns a measuring bob or spindle in a container filled with sample fluid. While the
driving speed is preset, the torque required for turning the measuring bob against the fluid’s
viscous forces is measured.
Rotational Device Types: In rotational viscometers there are two common approaches to measure
the torque.
Spring Devices: The motor - typically a stepper motor - drives the main shaft. A pivot and spring
assembly rotates on the shaft. The spindle with the measuring bob (rotor) is attached to this
assembly. As the spindle rotates, the spring is deflected proportional to the torque caused by the
viscosity of the sample under test.
This system provides high measurement accuracy at the cost of covering only a small measuring
range. The sensitive pivot bearing must be protected from undesirable influences and damage.
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Servo Devices: This viscometer type uses a servo motor to drive the main shaft. The spindle with
the measuring bob (rotor) is attached directly to the shaft. A high-resolution digital encoder
measures the rotational speed. The motor current is proportional to the torque caused by the
viscosity of the sample under test. The viscosity can be computed based on rotational speed and
current.
Compared to models with a pivot bearing and spring systems, viscometers with a servo motor
cover a wider measuring range and are more robust. The electronic decoder and motor allow for
greater torque and speed ranges than is possible with a mechanical spring. However, the accuracy
for low speeds and low viscosity is lower than for spring systems, as the friction of the motor and
bearing influences the measurement.
The shear rate at the surface of the bob can be calculated from the system's geometry and the
angular velocity. Likewise, the shear rate can be calculated from the measured torque and the
geometry. With shear rate and shear stress, you get the dynamic viscosity.
Specification
Power 230V AC, 50Hz, 20W
Accuracy ±1.0% of Full Scale Range
Reproducibility 0.2% of Full Scale Range
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Visual melting point apparatus
Melting point (MP) is the temperature at which a solid becomes a liquid at standard atmospheric
pressure; at this point, solid and its liquid are in an equilibrium at a certain pressure. Melting point is one of physical properties of a compound by which it is identified. This property is intrinsic to a
compound when it is pure. A pure crystalline compound has a sharp melting point. When a sample melts at a lower than expected temperature over an extended range, this is indicate that the
sample was impurity. Therefore, melting point of a compound can give indication of compound's purity and for identification. The melting point can be measured by melting point apparatus.
Determining the melting point of a compound is one way to test if the substance is pure. A pure substance generally has a melting range (the difference between the temperature where the
sample starts to melt and the temperature where melting is complete) of one or two degrees. Impurities tend to depress and broaden the melting range so the purified sample should have a
higher and smaller melting range than the original, impure sample. The Visual Melting Range Apparatus is completely based on ingenious concept for detecting melting point of polymers, wax, chemical powders, etc. Further, these systems can handle analysis and melting process monitoring of any type of colored sample. Moreover, these systems also feature automatic detection of melting range as well as advanced micro-controller based user control along with alphanumeric splash waterproof polyester soft keys.
Salient features:
Detects melting range or point of substances
Built-in calibration of automatic 2-point
Calibration with respect to data, date & time for authentication
Specifications
Make:LABINDIA Model: MR-VIS
Control type Microcontroller
Temperature sensor PT100
Temperature range Ambient +5˚C to 350˚C
Temperature readability 0.1˚C
Heating rates 0.2˚C/min to 12˚C/min
Max cooling time from 350˚C to ambient (25˚C) 25 minutes
Accuracy of detection of melting temperature a. Ambient+5˚C to 200˚C: ±0.5˚C b. 200˚C to 300˚C: ±0.8˚C
c. Above 300˚C: 1.4˚C
Sample size 5mg
Visual image 10X magnified image
Camera CCD
Power 230V±10%, 50Hz
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Conclusion This one week training was a very fruitful experience for me. It helped me to enhance my
knowledge regarding the various equipments that are being used in the pharmaceutical
field in modern times. The detailed study of the instruments helped me to understand the
principles which I have studied during my Engineering course.
I hope that this overview of the equipments will be of some help to Glenmark
Pharmaceuticals Ltd in the near future.