This study explores the possibility of combining LC/MS/MS production scan technology with GC/MS analysis to identify drugs and poisons in postmortem fluids and tissues.
This study aims to develop an LC/MS/MS screening method for drugs and poisons in postmortem fluids and tissues from Medical Examiner cases to augment the current screening procedures using GC/MS. The original intent of this method was to replace ELISA as an initial routine screening tool and to supplement GC/MS in the normal screening of all cases. During the validation of the new method and its application to real cases to evaluate its efficacy, variations were found between the LC/MS/MS and GC/MS test results. Ultimately, if successful, this new procedure would replace the ELISA screening procedure that was unable to provide the sensitivity and specificity required. The secondary goal was to develop a method that generates more spectral detail to provide a higher confidence in the identification of a substance and eliminate misidentifications. Preliminary research proved that this could be achieved by performing production scanning at three different collision energies and combining these product scans into a library-searchable spectrum. The process would be triggered using known MRM transitions for each compound. If the MRM was present, the product scan would be triggered, and the production scans would be collected. To accomplish these goals, funding was used to purchase a Shimadzu Model 8060 LC/MS/MS instrument with the required scanning speed and data collection rate to collect and collate the spectral data. In addition, the grant funding was used to purchase a centrifuge used in the sample preparation process and certified reference materials to be used in the preparation of the reference drug library.