What can gas chromatography/mass spectrometry do that other electronic detectors cannot?

Gas chromatography/mass spectrometry (GC/MS) is a powerful analytical technique primarily used for the identification and quantification of chemical substances. One of its standout features is its ability to differentiate between isomers and specific compounds within complex mixtures. In the context of crime scene investigation, particularly when analyzing fire debris or ignitable liquids, GC/MS can provide specific information about the chemical nature of the substances present.

Choosing between isomers—chemical compounds that have the same molecular formula but different structural formulas—is particularly challenging with simpler electronic detectors. They may only provide a general indication of the presence of a substance, without sufficient detail to specify which isomer is present. GC/MS, however, separates the compounds thermally through gas chromatography and then identifies them by their mass spectrometry signature, allowing forensic analysts to ascertain the precise nature of materials involved in a fire scene. This capability is crucial for investigations, helping to determine whether an ignitable liquid was used and potentially linking a suspect to the scene.

The other options, while relevant to forensic analysis, do not capture the unique distinguishing ability of GC/MS in fire investigations. For example, detecting all forms of fuel or measuring the intensity of fire damage do not require the sophisticated separation and identification that GC/MS provides. Similarly,