trace evidences for 2nd MBBS practical

1. TRACE EVIDENCES
Dr PRIYAL JAIN
SR Deptt. Of Forensic Medicine

2. Blood
Semen
Saliva
Urine
Feacal Matter

3. Blood
Physical examination
Chemical test / Colour Tests
Microchemical test
Spectroscopic examination
Microscopic examination

4. Chemical tests
Leucomalachite green
Orthotoludine test
Guaiacum test
Benzidine test ( blue colour)
Phenophthaline test / KM Test (pink colour)
peroxidase enzyme causes change in colour

5. Microchemical test
Teichman`s test / acid hematin test
NaCl + GAA + Stain = brownish black rhombic crystals
Takayama test / hemochromogen test
Reagent + stain = pink feathery hemochromogen
crystals
Positive with old stains, more delicate and reliable,
Can be subjected to spectroscopic examination
Luminol spray test(3-aminophthalhydrazide)
Old stains, minutr traces, non visible stains
When washed with cleaning agents like NH3 or bleach.

6. Species detection test
Precipitin test
Antiglobulin consumption / hemeagglutination
inhibition
Gel diffusion
Double diffusion in agar gel
Precipitaon electrophoresis
Passive hemeagglutination
Latex test

7. Semen
Physical examination
Chemical examination
Microscopic examination

8. Chemical examination
Florence test
dark brown crystals of choline iodide
Barberio test
yellow needle shaped rhombic crystals of spermin
picrate
Acid phosphatase
340-360 Bodonsky / ml ; 2500-3500 Angstrom
Creatine phosphokinase
> 400
Immunological methods
PSA or P30
choline and spermine test