Automated Sample Preparation for the Monitoring of Pharmaceutical and Illicit Drugs by LC-MS/MS

Automated sample preparation enables highly reproducible quantitative analyses while meeting the increased efficiency needs often required for sample processing in laboratories. This application note describes results obtained using a liquid handling-based automation system for the sample preparation of compounds to be analyzed by LC-MS/ MS and applied to the monitoring of multiple classes of pharmaceutical and illicit drugs. This screen panel contains 56 compounds that could be identified and quantified over a wide range of concentrations from 0.5X to 10X the cutoff value. In addition, the large majority of the compounds could be analyzed with accuracy over 80% and CV under 15%. This method provides automated capabilities for analytical laboratories that currently routinely process samples manually for the monitoring of these drugs in biological fluids. Introduction Liquid chromatography-tandem mass spectrometry provides laboratories with a powerful tool for accurate, multiplexed analysis of large panels of compounds. As a consequence, this technology is being increasingly applied to the forensic screening of urine samples, to monitor for the potential diversion of prescription pharmaceutical drugs. As the number of samples to be analyzed increases, the bench time required to process these samples, as well as the opportunity for errors in processing also increases. Automating the sample preparation prior to analysis by LCMS/ MS can increase the possible throughput, reduce the active bench time required to prepare even small numbers of samples, and minimize the number of human intervention points, thereby minimizing opportunities for error and maintaining the integrity of sample information. Automation can also eliminate the variability that is introduced by multiple technologists processing samples in slightly different fashions. In this work, we have utilized a Biomek 4000 Workstation (Figure 1) to automate the sample processing for the forensic screening of pharmaceutical drugs in human urine on an SCIEX Triple QuadTM 4500 LC/MS/MS system. Automated Sample Preparation for the Monitoring of Pharmaceutical and Illicit Drugs by LC-MS/MS SCIEX Triple QuadTM 4500 LC/MS/MS system and Beckman Coulter Biomek 4000 Workstation APPLICATION NOTE Figure 1A. Beckman Coulter Biomek 4000 Workstation. Figure 1B. SCIEX Triple QuadTM 4500 LC/MS/MS system.