Consolidating LC-MS/MS Method Conditions for the Analysis of Alcohol Metabolites, Barbiturates, and Drugs of Abuse

Efficiency is key when running multiple drug panels, and any way to save time or streamline a process can help reduce costs. To help simplify the analysis of alcohol metabolites, barbiturates, and drugs of abuse, three different methods were developed for each analyte class using the same analytical column and mobile phase setup. A panel of 129 drug and drug metabolite isobars in positive mode, negative mode drug and drug metabolites, and alcohol metabolites were all analyzed using a Force Biphenyl 50 x 3 mm, 2.7 µm analytical column and 0.1% formic acid in water and 0.1% formic acid in methanol mobile phases. The Force Biphenyl phase has unique selectivity due to the pi-pi interactions for drugs and drug metabolites when compared to a routine C18 phase allowing for improved resolution of isobars. Urinary interferences that are particularly problematic in alcohol metabolite testing were resolved without the use of buffer or additional mobile phases helping to streamline analytical testing processes.