Date of Award


Document Type


Degree Name

Master of Science (MS)


Department of Chemistry

First Advisor

Jun-Hyun Kim


Due to the worsening national drug epidemic and increasing prevalence of exceptionally potent synthetic opioids, there is a need to improve the forensic detection of illicit drugs, including sample analyses conducted on-site. In this thesis, the analysis of several illicit drugs spotted onto plasmonic surfaces was investigated using surface-enhanced Raman spectroscopy (SERS) with the goal of improving detection limits. Plasmonic surfaces (gold nanoparticle-loaded filter papers) were prepared and characterized prior to their SERS applications. Plasmonic surfaces were then further modified for improved SERS detection of each illicit drug with the treatment of self-assembled monolayer (SAM) forming compounds; in addition to the implementation of paper-spray ionization (PSI). Each of these modifications were optimized both independently and simultaneously for each drug through the screening process of many SAMs, durations of PSI, and SERS scan location on the sample surface. Finally, each combination of drug with optimal SAM and/or PSI optimization was calibrated to assess limits of detection. Limits of detection were found to be in the single-nanograms of drug deposited and improvements were observed in samples modified with SAMs and PSI.


Imported from Harms_ilstu_0092N_11888.pdf


Page Count


Available for download on Tuesday, July 15, 2025

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