SPECIMEN ASSAYS

Yenny Yustisia

Surface characterization

Contact angle analysis

Light microscopy

Electron microscopy

Light microscopy

an instrument that uses visible light and magnifying lenses to examine small objects not visible to the naked eye, or in finer detail than the naked eye allows

techniques Transmitted Light Microscopy is the general term used for any

type of microscopy where the light is transmitted from a source on the opposite side of the specimen to the objective lens

Inverted observing living cells or organisms

at the bottom of a large container (e.g., a tissue culture flask) under more natural conditions than on a glass slide

Bright Field (Khler illumination) Microscopy

Dark Field Microscopy

Phase Contrast

Polarised Light Microscopy

Differential Interference Contrast

Fluorescence Microscopy

Confocal Microscopy

Electron microscopy

a microscope that uses accelerated electronsas a source of illumination

Scanning Electron Microscopy (SEM)

Transmission Electron Microscopy (TEM)

CR

T

Detector

Amplifier

Electron gun

Condenser lens

Objective lens

Magnification control unit

Scanning circuit

Beam deflector

Specimen

Condenser lens

Specimen

Objective lens

Lampu

Intermediate lens

Projector lens

Projector screen

Penyinaran dan pembentukan bayangan pada MO, TEM, dan SEM

TEM SEMMO

Contact angle analysis

The force balance between the liquidvapor surface tension (lv) of a liquid drop and the interfacial tension between a solid and the drop (sl), manifested through the contact angle () of the drop with the surface, can be used to quantitatively characterize the energy of the surface (sv)

(a) Wetting system showing forces acting on the liquid drop.

(b) Nonwetting system with > 90 .

The basic relationship describing this force balance is:

sv = sl + lvcos

The energy of the surface, which is directly related to its wettability, is a useful parameter that has often correlated strongly with biological interaction.

Four possibilities for contact angle measurement: (A) sessile drop, (B) captive air bubble method, (C) capillary rise method, (D) Wilhelmy plate method.

Spectrophotometry to measure the amount of light that a sample absorbs.

The instrument operates by passing a beam of light through a sample and measuring the intensity of light reaching a detector

Infrared Spectroscopy

a simple and reliable technique widely used in both organic and inorganic chemistry

A Molecul was indentifed by its molecular vibration, based on the absorbtion and intensity of spesific infrared wavelengths

Provides information on functional groups

Assays for protein type and amount

High-Performance Liquid Chromatography (HPLC)

Colorimetric assays

Enzyme-linked Immunosorbent Assay (ELISA)

Western Blotting

High-Performance Liquid Chromatography (HPLC)

is a technique in analytic chemistry used to separate the components in a mixture, to identify each component, and to quantify each component

It relies on pumps to pass a pressurized liquid solventcontaining the sample mixture through a column filled with a solid adsorbent material

Each component in the sample interacts slightly differently with the adsorbent material, causing different flow rates for the different components and leading to the separation of the components as they flow out the column

Ex: detecting vitamin D levels in blood serum, separating the components of a complex biological sample, or of similar synthetic chemicals from each other

Colorimetric assays

Assays for the presence of a certain protein, based on changes in an observable quantity such as color

applicable to both organic compounds and inorganic compounds and may be used with or without an enzymatic stage

Fluorescent assays

Similar in concept to colorimetric assays

Key difference: reaction causes the attachment of a fluorescing molecule (fluorophore) to the protein of interest

Enzyme-linked Immunosorbent Assay (ELISA)

a test that uses antibodies and color change to identify a substance

For a very specific identification of a protein

Western Blotting

Assay to identify a certain protein after separation of the many proteins contained in a sample through the use of gel electrophoresis

Immunostaining

To identify the location of proteins in tissues and visualized via light microscopy

A primary antibody is added to the section bind protein of interest

Second Ab linked to and anzyme or chromophore binds primary Ab

Imaged under visible light

DNA and RNA assays

To determine gene mutation, damaged gene

Polymerase Chain Reaction (PCR)

Southern and Northern Blotting

Polymerase Chain Reaction (PCR) &Reverse-Transcription PCR

To expand the amount of DNA or RNA for that gene to detectable levels

Polymerase Chain Reaction (PCR) DNAReverse-Transcription PCR RNA