Gas chromatography with dual mass spectrometric and nitrogen–phosphorus specific detection: a new and powerful tool for forensic analyses

Abstract

Mass spectrometry in combination with gas chromatography (GC–MS) is nowadays state of the art for searching, confirmation and quantitation in the field of forensic analytics. With the aid of mass spectral libraries, unknown substances can be easily identified. Many forensic laboratories use a separate instrument with specific detectors like the nitrogen–phosphorus specific detector (NPD) for the search of general unknowns, involving absolute or relative retention indices. To our knowledge, no publications with both MS and NPD on the same instrument exist for forensic analyses. By the adaptation of the lengths of the analytical columns, differences in the absolute retention times could be minimized to fractions of a minute. We would like to present a technical improvement to combine and further enhance the analytical possibilities of two modern analytical techniques in the field of forensic analyses. Examples are presented from routine work: Analysis of an illicit powder suspected to contain drugs of abuse and a toxicological screening for basic drugs in human blood.