Advisory Committee Chair
Ellen Mwenesongole
Advisory Committee Members
Chris Dockery
Jason Linville
Document Type
Thesis
Date of Award
1-1-2025
Degree Name by School
Master of Science in Forensic Science (MSFS) College of Arts and Sciences
Abstract
Drug-facilitated sexual assault (DFSA) is an ongoing issue that remains significant in the United States and the World. DFSA can be either proactive or opportunistic, where a victim becomes impaired and is unable to provide consent. Common drugs found in DFSA cases are ethanol and cannabis. However, alternative drugs are increasingly being used to incapacitate a victim and enable a sexual assault. These include tetrahydrozoline (THZ), commonly found in over-the-counter eye drops, such as Visine®. Minimal research surrounds THZ, in which agencies may process case samples with a general drug screen, which may only detect common drugs, while THZ goes undetected. Additionally, due to delayed reporting, alternative samples are of interest in the absence of relevant biological samples, such as urine and blood. Therefore, additional investigation into the use of alternative samples, such as alcoholic beverage residue, may be of use. This study was conducted to develop and validate a method to detect THZ using a derivatizing reagent, pentafluoropropionic anhydride in ethyl acetate (PFPA), and solid-phase extraction (SPE) to increase the method's sensitivity. The method validation parameters assessed were repeatability, intermediate precision, linearity, LOD, LOQ, autosampler stability, interference studies, and freeze-thaw analysis. The repeatability and intermediate precision produced RSD% below 10% at 0.25, 0.50, and 1.00 μg/mL, demonstrating low variability. Derivatized THZ at high and low concentrations produce curves with an R-squared value of 0.99, displaying a linear response. The LOD and LOQ were determined to be 3.9 ng/mL and 15.6 ng/mL, respectively. Derivatized THZ was unstable for the 24-hour autosampler stability. However, in the freeze-thaw analysis, THZ remains stable when stored at -20°C over a week, producing an RSD% below 10% for all concentrations. THZ was detected in the presence of other compounds in the interference studies. When THZ standard and Visine® (containing THZ) were spiked in High Noon Lemon Vodka Seltzer, the majority of extracted samples produced ion ratios within 20% of the ion ratios of a neat THZ standard, showing that THZ can be reliably detected using the study’s method. The study found the method to detect THZ to be sensitive, specific, and precise.
Recommended Citation
Hampton, Alyssa Simone, "Detection Of Tetrahydrozoline In Alcoholic Beverage Residue Related To Drug-Facilitated Sexual Assault Using Gc-Ms" (2025). All ETDs from UAB. 6843.
https://digitalcommons.library.uab.edu/etd-collection/6843
Comments
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