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INORGANIC NANOPARTICLES
VINISHA.VM.PHARMACY
GITAM INSTITUTE OF PHARMACY
NANOPARTICLES
Uses and advantages of nanoparticles in
medicine
Some of the uses of nanoparticles in biology and medicine include:
Creating fluorescent biological labels for important biological markers and molecules in research and diagnosis of diseases
Drug delivery systems Gene delivery systems in gene therapy For biological detection of disease causing
organisms and diagnosis Detection of proteins Isolation and purification of biological molecules
and cells in research Probing of DNA structure Genetic and tissue engineering Destruction of tumours with drugs or heat be used.
In pharmacokinetic studies: Nanoparticles are being increasingly used in drug delivery systems. The advantages of using nanoparticles as a drug delivery system include:
The size and surface characteristics of nanoparticles can be easily manipulated. This could be used for both passive and active drug targeting
Nanoparticles can be made to control Nanoparticles can be made to control and sustain release of the drug during the transportation as well as the location of the release. Since distribution and subsequent clearance of the drug from the body can be altered, an increase in drug therapeutic efficacy and reduction in side effects can be achieved
Choosing an appropriate matrix also helps in increasing the efficacy and reducing side effectsTargeted drugs may be developedVarious routes of administration including oral, nasal, injection, intra-ocular (within the eyes) etc. can be used.
TYPES OF NANOPARTICLES
Gold Nanoparticles
Introduction
AuNPs also called as Gold Colloids.Colloidal gold is a sol or colloidal suspension of submicrometre size nanoparticles of gold in a fluid, usually water. The liquid appear deep red to black in solution. In fact, a whole range of colours can be observed depending on the size of the AuNPs.
Synthesis
TURKEVICH METHOD:
10 ml of 0.002 M aq. chloroauric acid H[AuCl4]
Stir for 15 minutes at 800 C Add 10 ml of 0.01 M aq. Sodium Citrate Stir for 30 minutes at 800 C Clear Solution turns to red indicating
formation of Gold nanoparticles
Characterization TEM (Transmission Electron Microscopy) SEM (Scanning Electron Microscopy) Gel Electrophoresis UV-Visible spectroscopy Dynamic Light Scattering (DLS)
SEM image of colloidal gold
TEM image of colloidal gold
Applications
1.As conductors from printable inks to electronic chips. 2. To detect various cancers like breast cancer and oral cancer, and other diseases like neoplasia and rheumatoid arthritis. 3. For cancer therapy to eradicate targeted tumors.
4. Lasers that react with AuNPs could be used to
destroy cancer cells.
5. To optimize the bio-distribution of drugs to
diseased organs, tissues or cells, in order to
improve and target drug delivery.
6. As catalyst in number of chemical reactions.
Gold and palladium nanoparticles can be used to break TCE, a water contaminant, into non-toxic constituents. Glass beads hold the nanoparticles in place and water is pumped through the nanoparticles from the bottom up.
Gold nanoparticles direct heat from infrared lasers to target cancer tumors.
They can also detect early stage Alzheimer’s
Silver nanoparticles
INTRODUCTIONINTRODUCTION
Silver nanoparticles have a noble metallic structure and because of their unique properties they are widely used in different fields.
Such as in catalysis , optics, nanotechnology, and bio engineering.
Silver nanoparticles are prepared by several techniques like chemical reduction , electrochemicalmethods,photochemical methods , and bio chemical methods.
SYNTHESIS OF SILVERNANOPARTICLES
INTRODUCTION: Recently, nanoparticle (NP) synthesis is among the
most interesting scientific fields.
Broadly speaking, there are two approaches to
nanoparticle production:
* Top-down: milling generates small particles from the
corresponding bulk materials
* Bottom-up: produces nanoparticles by starting from
the atomic level
There is growing attention to produce
nanoparticles (NPs) using environmental friendly
methods (green chemistry).
* Green synthesis approaches include
polysaccharides, biological and irradiation
methods which have advantages over
conventional methods involving chemical agents
associated with environmental toxicity.
Various physical, chemical and biological synthetic methods have been developed to obtain silver nanoparticles (Ag NPs) of various shapes and sizes.
Methods for synthesis of silver nanoparticles
A. Physical approaches1) Evaporation-condensation2) Laser ablation
28
B . Chemical approaches
1) Reduction by tri-sodium citrate 2) Reduction by sodium borohydride 3) UV irradiation4) Gamma irradiation 5) Laser irradiation6) Microwave irradiation7) Sonochemical reduction8) Sonoelectrochemical method 9) Electrochemical method
10) Polysaccharide method 11) Tollens method
C. Biological approaches 1) Synthesis of Ag NPs by bacteria
2) Synthesis of Ag NPs by fungi
3) Synthesis of Ag NPs by plants
A) Physical approaches The most important physical approaches include
evaporation-condensation and laser ablation.
1) Evaporation-condensation
Vaporize the material into gas, and then cool the gas.
a) Using a tube furnace has some disadvantages
The tube furnace consumes a great amount of energy.
Raises the environmental temperature around the
source material.31
Requires power consumption of more than several kilowatts
Requires a preheating time of several tens of minutes to reach
a stable operating temperature.
b) Using a small ceramic heater with a local heating source
The evaporated vapor can cool faster than tube furnace.
This physical method can be used for:
1. Formation of small nanoparticles in high concentration.
2. Formation of nanoparticles for long-term experiments for
inhalation toxicity studies.32
B) Laser ablation Laser ablation of metallic bulk materials in solution.
Laser ablation can vaporize materials that cannot readily
be evaporated.
33
Laser ablation in
liquid medium
Advantages of laser ablation technique compared to
other methods for production of metal colloids:
1. Absence of chemical reducing agents
2. Pure and uncontaminated metal colloids can be prepared
by this technique.
34
9) Electrochemical method
It is possible to control particle size by adjusting the
electrolysis parameters and to improve homogeneity of
Ag NPs by changing the composition of the electrolytic
solution.
PVP can be used to protect Ag NPs from agglomeration,
significantly reduces silver deposition rate and promotes
silver nucleation & Ag NPs formation rate.35
Electrochemical method for
synthesis of Ag NPs
36
The rate of reaction was found to increase with:
– Decrease in the distance between the electrodes (1–2 cm)
– Increase in the voltage (5–50 V DC)
– Increase in the temperature
A longer reaction time resulted in:
– Larger size of Ag NPs
– Higher concentration of Ag NPs37
Alternatively, the cathode could be other metals such
as platinum.
The presence of PVA (1–100 ppm):
– Acts as supporting electrolyte
– Accelerates the NP nucleation and growth
– Produces highly concentrated suspensions of NPs
38
39Electrochemical method for synthesis of Ag NPs
40
Silver nanoparticles
SEM
Uses of silver nanoparticles USES OF SILVER NANOPARTICLES:
In refrigerators, washing machines, air-conditioners, clothing, baby pacifiers, food containers, detergent, surgical instruments, etc.
SILICA NANOPARTICLES
Silicon dioxide nanoparticles, also known as silica nanoparticles or nanosilica, are the basis for a great deal of biomedical research due to their stability, low toxicity and ability to be functionalized with a range of molecules and polymers. Nano-silica particles are divided into P-type and S-type according to their structure..
SYNTHESIS OF SILICA NANOPARTICLES
Preparation of silica nanoparticles
APPLICATIONS
IRON OXIDE NANOPARTICLES
SYNTHESIS
APPLICATIONS
Applications:The key applications of iron oxide nanoparticles are as follows: 2. In magnetic resonance imaging to provide enhanced contrast at very low concentrations in the nanomolar range for studying tumors 3. As a targeted delivery vehicle and as a drug delivery coating for nanoscale anti-cancer drugs 4. For magnetic data storage In coatings, plastics, nanowires, nanofibers, and textiles and in specific alloy and catalyst applications
IRON OXIDE RECENT FOCUS IN NANOMEDICINE:
**** Nanomedecine is an emerging interdisciplinary research field related to the use of hybrid nanoparticles in life sciences, especially for improvement of diagnosis, prevention and treatment of disease. Within the different chemical compositions of nanomaterials, superparamagnetic iron oxide nanoparticles (SPIONs) are certainly the most promising material for medical applications. *** The most commonly utilized forms of magnetic nanoparticles are the iron oxide γ-Fe2O3 (maghemite)andFe3O4(magnetite). *** Below approximatively 30 nm in size, such particle exhibit superparamagnetism. Briefly, the nanoparticles consist of single crystal domain and thus present a single magnetic moment. With the help of thermal energy, however, the magnetic moment can overcome the anisotropy barrier and spontaneously flip from one direction of anisotropy to another thus, the net magnetization of a particle averages to zero.
***A collection of magnetic nanoparticles consequently displays negligible magnetic remanence. When placed inside an external magnetic field, the magnetic moments align in the direction of the field lines and yielding a fixed magnetization direction. *** The intrinsic interaction of magnetic nanoparticle with applied magnetic field gradients makes these particles attractive for a large panel of biomedical applications such as immunoassays, imaging, nanovehicles and drug carriers or hyperthermia.
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