Author ORCID Identifier

https://orcid.org/0009-0002-8623-3050

Semester

Spring

Date of Graduation

2025

Document Type

Thesis

Degree Type

MS

College

Eberly College of Arts and Sciences

Department

Forensic and Investigative Science

Committee Chair

Luis Arroyo

Committee Co-Chair

Tatiana Trejos

Committee Member

Tatiana Trejos

Committee Member

Sunil Sharma

Committee Member

Marc LeBeau

Abstract

Sexual assault affects over 400,000 Americans annually, including 13% of college students, yet only 2.5% of assailants face incarceration. This disparity stems from significant challenges in evidence collection, particularly in drug-facilitated crimes (DFCs). Victims often delay reporting due to fear, self-blame, or unawareness of the assault which is common in cases involving substances like γ-hydroxybutyric acid (GHB). Current forensic standards rely on blood and urine, which offer detection windows of just 48 and 120 hours, respectively. These short timeframes frequently fail to capture critical toxicological evidence, leaving investigators with only victim testimony, which the judicial system struggles to act upon without corroborating physical proof. To address this gap, this thesis explores hair as an alternative matrix, capable of retaining drug evidence for a minimum of two months and providing a chronological toxicological profile.

Hair analysis, while promising, faces significant hurdles. Unlike blood or urine, it requires time-consuming preparation before extraction can begin. External factors such as cosmetic products, UV exposure, and contamination can alter drug concentrations, and no standardized protocols exist for analysis or interpretation. These challenges are amplified when targeting GHB. GHB’s endogenous presence in humans, short half-life (t1/2 = 30 minutes), and large inter-individual variation prevents the establishment of universal concentration cut-off. Instead, individuals must serve as their own baselines, though interpreting such data lacks consistency.

A comprehensive literature review revealed gaps in extraction techniques, decontamination protocols, and analytical workflows, highlighting the need for standardized forensic approaches to differentiate endogenous from exogenous GHB. This research developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to detect GHB and other DFC drugs in hair, achieving effective separation using C18 and hydrophilic interaction liquid chromatography (HILIC) columns in both positive and negative ionization modes. Three extraction methods, NaOH digestion, methanol solvent swelling, and M3 reagent, were evaluated for GHB recovery. The M3 reagent proved most reliable, yielding approximately 30% recovery across 11 trials, though matrix-dependent variations emerged when comparing synthetic hair, authentic human hair, and hydrolyzed keratin.

Despite these advancements, full method validation was not achieved within the study’s timeframe due to GHB’s low recovery, signal suppression, and matrix effects. Nevertheless, this work provides practical contributions: optimized mass spectrometry transitions, two chromatographic separation methods, and methodological guidance for forensic scientists. Experimental and literature evidence confirmed GHB’s complexity as a target analyte, while the study demonstrated awareness and identified key challenges for future resolution.

Download

Share

COinS