LC/MS with a particle beam interface in forensic toxicology.

Many instruments are used in forensic toxicology to screen biologic samples for drugs and other compounds. Many of these screening instruments (and others) are used to confirm positive screening tests. The focus of this article is the use of a high pressure liquid chromatograph/mass spectrometer (HPLC/MS) for screening forensic postmortem and human performance DWI cases. This screening procedure involves an HPLC with a particle beam interfaced to a mass spectrometer detector and a photodiode array detector. Drugs such as the antidepressants, drugs of abuse, over-the-counter cold and pain preparations, anticonvulsants, benzodiazepines, and some medications that are not available in the United States are selected at therapeutic and subtherapeutic levels. Limits of detection and extraction efficiencies are presented for many compounds. Several cases are discussed showing different drug combinations.