ORCID
https://orcid.org/0009-0003-0663-2068
Keywords
Hair, Forensic, Toxicology, LA-ICP-MS, MALDI-MS, Laser
Abstract
In forensic toxicology, human hair is a valuable biological matrix for assessing exposure to illicit drugs and toxic elements. Hair provides an extended detection window of analytes, allowing for evaluation of exposure history related to time. Laser-based analytical techniques offer direct analysis with minimal destruction, a quality essential in forensic investigations where sample preservation is crucial. However, accurate quantitative analysis relies on calibration standards that replicate the chemical and physical properties of its target matrix. Current standards relied on in industry and research do not adequately reflect the complex chemical composition of hair, resulting in sample matrix effects and compromised analytical accuracy. Therefore, there is a critical need for the development of a matrix-matched standard for chemical profiling of human hair.
This dissertation presents the synthesis of a keratin-based material extracted from human hair. The material was designed for use by laser-based elemental and molecular analysis. The material was doped using two methods: toxic elements for Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) and drug metabolites for Matrix Assisted Laser Desorption Ionization-Mass Spectrometry (MALDI-MS) Imaging. The reference material was characterized for its morphology, homogeneity, and stability for suitability as a calibration standard for laser-ablation. The standard was evaluated in comparison to doped human hairs demonstrating low limits of detection with accurate quantitation.
Collectively, these findings contribute to the advancement of forensic toxicology providing a reproducible matrix-matched standard for quantitative determination of toxic metals and drug metabolites in human hair. The development of this reference material paves the way for a new set of calibration standards within forensic investigations.
Completion Date
2025
Semester
Fall
Committee Chair
Baudelet, Matthieu
Degree
Doctor of Philosophy (Ph.D.)
College
College of Sciences
Department
Chemistry
Format
Release Date
12-15-2027
Document Type
Dissertation
Campus Location
Orlando (Main) Campus
Subjects
Hair--Toxicology; Hair--Analysis; Mass spectrometry--Forensic applications; Analytical toxicology; Forensic toxicology
STARS Citation
Bonilla, Kaitlyn A., "Development of a Stable Matrix-Matched Standard for Molecular and Elemental Analysis of Hair in Forensic Toxicology" (2025). Graduate Thesis and Dissertation post-2024. 526.
https://stars.library.ucf.edu/etd2024/526
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