Trace Analysis (ppt) Via LC/MS/MS to Assess Removal of Various Pharmaceutical Compounds by Activated Carbon Based Drinking Water Filters

摘要

Sensitive LC/MS/MS methods were developed to quantitate low (pg/mL) concentrations of pharmaceutical compounds in water following recent news stories and peer reviewed articles reporting on the presence of trace levels (ppt) of pharmaceutical compounds in wastewater and surface water. These methods were developed to evaluate the ability of water filtration systems to remove trace levels of various pharmaceutical compounds (i.e. common pain relievers, hormones, anti-anxiety and anti-infective drugs). The activated carbon based filters were very effective at removing the various cocktails of pharmaceutical compounds spiked into water. In order to quantitatively determine the percent removal, LC/MS/MS based methodologies were developed that had the ability to quantitate drug levels that were reduced by 99.98percent. This level of reduction relates to a limit of 200 ppt in filtered water and was achieved using SPE and 1000-fold concentration prior to injection. The quantitation range for all 12 compounds tested was 0.2 ng/mL to 40 ng/mL. Sample preparation and HPLC/MS/MS methodology were standardized such that the same type of SPE cartridge, HPLC column and mobile phase were utilized for all classes of compounds tested.