Following a shooting arrest, the investigating officer must collect samples from the suspect's hands for subsequent SEM-EDX analysis. The preferred collection method is:

• A Moist cotton swabbing of both palms
• B Taking paraffin casts of both hands for dermal nitrate testing
• C Washing the hands with dilute nitric acid and analysing the solution
• D Pressing adhesive aluminium stubs against the hand surfaces ✓

Explanation

SEM-EDX requires individual particles on a flat conductive mount, so adhesive stubs or tape lifts pressed onto the hands recover intact particulate residue directly compatible with the instrument stage. Swabbing dissolves and dilutes particles in a matrix unsuitable for SEM, acid washing destroys the sample, and paraffin casting belongs to the obsolete dermal nitrate test, which lacked specificity and is no longer accepted as evidence.

Reference: Saferstein, Criminalistics: An Introduction to Forensic Science, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.