Derivatization

Gas chromatography-mass spectrometry (GC-MS) is still one of the most widely used analytical techniques in the forensic toxicology laboratory. Chemical derivatization is used to enhance the volatility, temperature stability, and detectability of drugs. It is an unavoidable requirement for some drugs and metabolites, particularly those with polar functional groups. Although chemical derivatization is an additional sample preparation step, chromatographic characteristics, stability, and overall improvements in detectability and specificity can be achieved. The most common derivatization techniques include silylation, acylation, and alkylation. A wide variety of derivatization reagents can be employed for this purpose. Approaches to derivatization are discussed for drugs of forensic interest, including amphetamines, benzodiazepines, cocaine metabolites, and opiates.