Comprehensive Urine Drug Screen by Liquid Chromatography-Quadrupole Time of Flight Mass Spectrometry

Current trends in drug use include polydrug use as well as an ever-changing landscape of novel psychoactive substances. Immunoassay-based urine drug screens limited to classic drugs of abuse do not have the scope necessary to identify patients with drug intoxications or drug misuse. Mass spectrometry is an alternative method that is both sensitive and specific. In this chapter, we present a liquid chromatography-quadrupole mass spectrometry-based method for qualitative comprehensive urine drug screening. The method runs in positive mode and encompasses over 1000 basic compounds, including pharmaceutical, illicit, and novel drugs. Retention time, MS and MS/MS spectra, mass error, and isotope confidence are parameters used for compound identification. New compounds are readily added as new recreational drugs emerge.