Defense Date
2023
Document Type
Directed Research Project
First Advisor
James Hutchings, Ph.D.
Second Advisor
Michelle Peace, Ph.D.
Third Advisor
Ashley Pierce, M.S.
Abstract
Calibrators and controls are an integral part of forensic toxicology. The Virginia Department of Forensic Science (DFS) utilizes blank human blood prepared from human packed red blood cells (RBCs) for calibrators and controls. Because blank blood must be negative for analytes of interest to be used for calibrators and controls, many lots of blank blood are unsuitable for use. Animal blood as an alternative matrix is a possible solution to the increasing prevalence of analytes in human blank blood. This work sought to validate the DFS liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the confirmation and quantitation of benzodiazepines using whole horse blood for calibrators and controls. Method validation was performed according to the ANSI/ASB Standard 036 guidelines for method validation in forensic toxicology. Failure to meet the predetermined validation acceptance criteria was observed for the horse blood and blank blood calibration curves in the bias, precision, limit of detection (LOD), and limit of quantitation (LOQ) studies. Because the method was previously validated in 2012 according to the Scientific Working Group for Forensic Toxicology (SWGTOX) method validation guidelines, differences in validation acceptance criteria were observed and are the reason the method did not meet the ANSI/ASB Standard 036 validation criteria. Revalidation of the DFS benzodiazepine method according to the ANSI/ASB Standard 036 method validation guidelines is needed. This work also indicated the potential usefulness of horse blood and the need for further studies using animal blood for commonly encountered analytes in forensic toxicology.
Rights
© The Author(s)
Is Part Of
VCU Master of Science in Forensic Science Directed Research Projects
Date of Submission
5-2-2023