DOI: 10.3886/icpsr39085
title: Combining LC-MS/MS Product-Ion Scan Technology with GC-MS Analysis to Identify Drugs and Poisons in Postmortem Fluids and Tissues, Florida, 2019-2022
title: Archival Version

description: The Miami-Dade County Medical Examiner Department (MDME) successfully conducted preliminary studies that evaluated the effectiveness of fast scanning liquid chromatography-tandem mass spectrometry (LC/MS/MS) which created a detailed merged-product ion scan spectra with library search capabilities to identify substances more accurately. The project intent was to establish its effectiveness in replacing more traditional immunoassay testing procedures that are costly, of limited scope, non-specific, and can only provide presumptive results. The goal was to develop a superior screening protocol that combines fast scanning LC/MS/MS technology with the currently utilized gas chromatography mass spectrometry (GC/MS) screening technique. By merging these two analytical tools, GC/MS and LC/MS/MS, a broader range of drugs can be identified more efficiently and at appropriate drug concentrations for postmortem analysis.
description: The principal goal of this project was to develop a fast scanning liquid chromatography-tandem mass spectrometry (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 gas chromatography mass spectrometry (GC/MS). Ultimately 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. The essential goals were to:

Establish suitable instrument conditions to scan for 400 drugs in a single analysis, while retaining low detection limits and detailed spectra.
Create a searchable spectrum library that includes relevant drugs found in a traditional toxicology
screen that contained a searchable composite product-ion spectra.
Development of a rapid broad scope sample preparation technique (extraction) of postmortem
fluids and tissues suitable for a comprehensive screening method.
Replace ELISA drug screening with the new method.
Correlate of test results with GC/MS testing method currently used.
Improve testing process and turnaround time using the new LC/MS/MS screening method.
description: Please see the final report (linked in the Data Related Publications tab) for technical details about study procedures, sample preparation, and analysis.
description: The Principal Investigator provided one Excel file of summary data broken out into three worksheets.

<strong>Worksheet 1 (Compound List):</strong> Details all compounds and their reference ions, retention time, product ions, collision energies, and other mass spectrometer parameters.
<strong>Worksheet 2 (Validation Data):</strong> Experimental data determining limit of detection of each compound.
<strong>Worksheet 3 (Method Comparison):</strong> Cases retroactively analyzed on the newly created method, as compared to older methodologies in the laboratory.
description: Datasets: 
DS1: Combining LC-MS/MS Product-Ion Scan Technology with GC-MS Analysis to Identify Drugs and Poisons in Postmortem Fluids and Tissues, Florida, 2019-2022
description: record abstractsAdditional data was deposited with ICPSR as a compressed .zip file that includes Shimadzu data files (.lcd and .lcm) used with and acquired from Shimadzu instrumentation. This file was designated by NIJ for archival only. Additionally, the Miami-Dade County Medical Examiner is not capable of providing independent means to review or access this data without Shimadzu Labsolutions software suite.Some additional terminology used in-house by the Principal Investigators.

SCLCMSMS: the method developed through the instrumentation purchased with this grant
SCRNZ / Z: a blood drug screen method by GC-MS-NPD
SCGEN / GEN: a blood drug screen method by LC-ion trap-MSn
SCELISA / ELISA: immunoassay kit purchased through Neogen