Screening of Urine and Blood Using Limited Sample Preparation and Information Dependent Acquisition with LC-MS/MS as Alternative for Immunoassays in Forensic Toxicology

Screening of Urine and Blood Using Limited Sample Preparation and Information Dependent Acquisition with LC-MS/MS as Alternative for Immunoassays in Forensic Toxicology

Immunoassays are widely used to perform an initial toxicological screening of biological samples. However, LC-MS/MS is described as a promising technique that can overcome the limitations of immunoassays (such as their lack of selectivity). The objective of this project was to implement a LC-MS/MS method for screening of forensic ante- and post-mortem urine and whole blood samples that can replace the immunoassays. Easy and rapid sample preparation techniqueswere evaluated. Protein precipitation with acetonitrile combined with aqueous dilution (dilution factor 5 for urine and 10 for blood) proved to be an effective procedure. On the LC-MS/MS, 1 scheduled multiple reaction monitoring transition for each of 414 compounds was analyzed in positive mode, followed by an enhanced product ion scan if the peak height exceeded a specified threshold.