Unger, Kirk2019-12-042019-12-042019-11-13https://laurentian.scholaris.ca/handle/10219/3379Blood microsampling techniques, like Dried Blood Spots (DBS), have seen recent development as an alternative to wet blood samples and offer numerous advantages. Quantification of ng/mLrange concentrations using DBS microvolumes (10-20 µL) is made possible with cutting edge instrumentation. Worldwide establishment of per se limits for drug impaired driving requires timely methods of sampling blood for accurate drug concentration measurements and interpretation. The method validation for the analysis of stimulants and metabolites in DBS samples by Ultra Performance Liquid Chromatography-Quadrupole Time of Flight-High Resolution Mass Spectroscopy (UPLC-QTOF-HRMS) is presented. Limits of detection and quantitation to 10 ng/mL was achieved. Method validation criteria was satisfied for 10 of 14 analytes. DBS drug stability over 8 weeks varied by analyte. DBS samples may assist in overcoming challenges in blood sampling as they are less invasive, easily transported and stored, and accurate drug quantitation even at low concentrations in DBS samples is possible.endried blood spotsDBSmicrovolume samplingQTOFhigh resolution mass spectrometryforensic toxicologyThesis