Instruments used in forensics

Analytical Instrumentation

For quantitative forensic analysis, specialized instruments are used. A variety of analytical instruments exist, which have their respective advantages depending on what is being examined and the potential target molecules that could be contained within it.

 

 

Laboratory analytical techniques for identification:

1. Electrophoresis - many substances carry an electrical charge
2. Spectrophotometry - the absorption of light by a substance
3. Chromatography - a means of separating the components of substances
4. Mass Spectrometry - combined chromatography and spectrophotometry
5. Atomic Absorption/Emission - the spectra of colors when atoms are excited
6. Neutron Activation - the measurement of gamma ray radioactivity
7. X-Ray Diffraction - the bending of X-rays off the atomic planes of a substance

  ELECTROPHORESIS: involves putting substances in a gel or liquid, applying a positive and negative charge to each end, and forcing components in the substance to migrate across the gel. Among other things, it's a quick and easy way to separate organic from inorganic matter because all proteins carry an electrical charge (and migrate at known speeds). It's commonly used in blood and DNA samples.

 

 

 

 

 

FORENSIC DOCUMENT EXAMINATION INSTRUMENTATION:

The Electrostatic Detection Apparatus (ESDA), used for indented writing detection, and the Video Spectral Comparator (VSC), for UV/IR imaging in reflection/absorption and fluorescence modes, are two of the most important instruments used in the examination of questioned documents.

 

 

 

 

 

 

 

 (To Be contd...)