For Biochemical Investigations
The blood and CSF from the cadaver may be collected for various biochemical examinations.
Collection of Gastric Aspirate
It is the duty of every medical officer to collect and preserve the gastric lavage sample in all cases of poisoning. The first wash should always be done with plain water and the returning sample should be preserved in a saturated solution of sodium chloride. In the subsequent washes, the antidotes should be added and continued till the returning fluid is clear and odorless. The preserved sample should be packed, labeled, sealed and handed over to the investigating officer after obtaining a due receipt from him.
Collection of samples for DNA finger printing
- A fresh blood sample is collected in any anti–coagulant bulb. Heparin is not advisable as it interferes with the activity of certain restriction enzymes.
- Buccal epithelial cells – from buccal smears.
- Amniotic fluid, chorionic villi are collected by medical procedures.
As far as possible, a DNA extraction should be started immediately. But, if the procedure is to be delayed for more than 48 hours, samples should be stored at –20 to –80°C.
- Dried stains should be collected in clean and dry envelopes and maintained in clean, dry and frozen state.
- Autopsy tissues should be wrapped in aluminum foil, placed in clean plastic bags and frozen immediately.
- Every sample should be properly labeled and labels should be kept inside storage containers.