Which analytical technique is often used in toxicology for drug testing?

Which analytical technique is often used in toxicology for drug testing?

• A. Electrophoresis
• B. Gas chromatography-mass spectrometry (GC-MS)
• C. Infrared spectroscopy
• D. Polymerase chain reaction (PCR)

Answer: (B)

Gas chromatography-mass spectrometry (GC-MS) is a powerful analytical technique frequently employed in toxicology for drug testing due to its high sensitivity, specificity, and ability to analyze complex mixtures. In toxicology, accurate identification and quantification of substances are critical, particularly in cases of overdose or poisoning. GC-MS allows for the separation of volatile and semi-volatile compounds, which are then identified based on their mass-to-charge ratio. The process starts with gas chromatography, where the sample is vaporized and passed through a column to separate its components based on their volatility. The separated compounds are then introduced into the mass spectrometer, where they are ionized and fragmented. The resulting ions are analyzed, producing a unique mass spectrum for each compound. This enables forensic scientists to detect trace amounts of drugs and metabolites, making GC-MS the gold standard in toxicological analysis. Other methods, while useful in various contexts, do not match the combination of sensitivity and specificity offered by GC-MS. Electrophoresis, for example, is useful for separating biomolecules but may not provide the same level of detail for small molecules like drugs. Infrared spectroscopy is valuable for identifying functional groups but lacks the resolution to effectively differentiate similar compounds in a complex mixture. Polymerase chain

Gas chromatography-mass spectrometry (GC-MS) is a powerful analytical technique frequently employed in toxicology for drug testing due to its high sensitivity, specificity, and ability to analyze complex mixtures. In toxicology, accurate identification and quantification of substances are critical, particularly in cases of overdose or poisoning. GC-MS allows for the separation of volatile and semi-volatile compounds, which are then identified based on their mass-to-charge ratio.

The process starts with gas chromatography, where the sample is vaporized and passed through a column to separate its components based on their volatility. The separated compounds are then introduced into the mass spectrometer, where they are ionized and fragmented. The resulting ions are analyzed, producing a unique mass spectrum for each compound. This enables forensic scientists to detect trace amounts of drugs and metabolites, making GC-MS the gold standard in toxicological analysis.

Other methods, while useful in various contexts, do not match the combination of sensitivity and specificity offered by GC-MS. Electrophoresis, for example, is useful for separating biomolecules but may not provide the same level of detail for small molecules like drugs. Infrared spectroscopy is valuable for identifying functional groups but lacks the resolution to effectively differentiate similar compounds in a complex mixture. Polymerase chain