Development and Optimization of a Rapid and Comprehensive Drug Screening Method in Urine by LC-MS/MS
Date of Award
Spring 5-28-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department/Program
Forensic Science
Language
English
First Advisor or Mentor
Marta Concheiro-Guisan
Second Reader
Gail Cooper
Third Advisor
Damon Borg
Abstract
Urine remains a critical matrix for toxicological analysis in clinical and forensic settings due to its noninvasive collection and longer detection window for parent drugs and metabolites compared to blood. However, traditional sample preparation techniques, such as solid phase extraction (SPE) and liquid-liquid extraction (LLE) are often time consuming, expensive, and too selective for general screening. This study aimed to develop and optimize a fast and simplified LC-MS/MS method for a comprehensive panel of 89 drugs, starting with the “crash-and-shoot” and “dilute-and-shoot” protocols. Experimental optimization of the crash-and-shoot procedure demonstrated that adding hydrolysis, removing 600 µL of supernatant, and adjusting the electron multiplier voltage (EMV) to +/- 200 resulted in a substantial increase in sensitivity across the entire drug panel as shown by significantly enhanced drug responses. A modification that used ice-cold acetonitrile (ACN) for protein precipitation which yielded mixed results for various analytes was also added. It was ultimately incorporated to maintain consistency with established toxicological standards. A comparative analysis of matrix effects revealed that the dilute-and shoot protocol was more effective at minimizing ion suppression and enhancement, especially for high concentration samples, compared to the crash-and-shoot method which showed extreme variability. Furthermore, the dilute-and-shoot procedure proved more time efficient and cost effective. Limit of detection and full validation studies should be completed before implementation in professional laboratories.
Recommended Citation
Seelall, Avani, "Development and Optimization of a Rapid and Comprehensive Drug Screening Method in Urine by LC-MS/MS" (2026). CUNY Academic Works.
https://academicworks.cuny.edu/jj_etds/397
