Which instrument has the capability of confirming the presence of a drug residue in the tissue of food animals with a 99% accuracy?

• A. Gas chromatograph
• B. High speed ultra centrifuge
• C. Mass spectrometer
• D. Recording spectrophotometer

Answer: (C)

When you need to confirm a drug residue in animal tissue with high certainty, you rely on an instrument that can definitively identify the chemical present. A mass spectrometer does this by measuring the mass-to-charge ratio of ionized molecules and analyzing their fragmentation pattern, producing a unique molecular fingerprint for the compound. This allows precise confirmation of the residue’s identity, especially when paired with chromatography to separate complex mixtures; together, GC-MS or LC-MS methods are standard for definitive residue testing and can achieve very high accuracy, often cited around the 99% range when validated properly. In contrast, a gas chromatograph alone only separates compounds and does not confirm identity, a spectrophotometer measures absorbance without providing specific molecular structure, and an ultracentrifuge is used for physical separation rather than identification. So the mass spectrometer is the tool that provides definitive confirmation of a drug residue in tissue.