Physical Sciences and Mathematics Commons^™

The Use Of Electrospun Nanofibers With Gold And Silver Nanostars For The Detection Of Fentanyl Using Surface Enhance Raman Spectroscopy, The Modification Of Current Gc-Ms Methods To Increase Separation And Detection Of Synthetic Cathinones In Mixtures, Daniel Rubin

FIU Electronic Theses and Dissertations

Many criminal cases involve the use or sale of illicit substances. The forensic analyst has many different techniques they can use to analyze samples to determine which illicit substance is present. This project aims at developing electrospun nanofibers with nanoparticles to analyze fentanyl by surface enhanced Raman spectroscopy, as well as modifying current GC-MS parameters to enhance separation and analysis of synthetic cathinones. Using the fibers with nanoparticles allowed for the detection of fentanyl standards at 1mg/ml while slowing the oven ramp rate and modifying the hold times led to an increase in separation and better fragmentation patterns for determination. …

Surface Enhanced Raman Spectroscopy (Sers) As A Nanoscale Adsorption Phenomenon: Development Of Tailored Nanomaterials For Applications In Drug Detection, Chiara Deriu

FIU Electronic Theses and Dissertations

Surface Enhanced Raman Spectroscopy (SERS) is an analytical technique in which nanostructured substrates amplify the inherently weak Raman signal of an adsorbed species by several orders of magnitude, enabling the detection of trace compounds, up to the single molecule level. While this may be an exceptional tool for any analytical scientist, SERS is at present relegated to the role of academic sensation, and is underutilized in everyday analytical practice. The SERS community is increasingly attributing this setback to a poor understanding of nanoscale surfaces and their chemical environment; since molecular adsorption at the nanostructured surface enables SERS detection, uncertainty about …

The Development Of A Surface Enhanced Raman Spectroscopy Method For The Detection Of Synthetic Cannabinoids In Urine, Thaddeus Mostowtt

FIU Electronic Theses and Dissertations

The use and abuse of synthetic cannabinoids has increased significantly in recent years due to their easy access and growing popularity. Despite having more known drugs become illegal, new synthetic versions of these drugs are being made that have not yet been recognized or classified as illegal substances. Therefore, standard methods may not be able to detect these drugs.

The most common method of screening detection for drugs of abuse in biological samples is the immunoassay. However, the immunoassay method presents some disadvantages, particularly for newly synthesized compounds. More advanced methods have also been used, such as LC-MS; however, these …

In Situ Arsenic Speciation Using Surface-Enhanced Raman Spectroscopy, Mingwei Yang

FIU Electronic Theses and Dissertations

Arsenic (As) undergoes extensive metabolism in biological systems involving numerous metabolites with varying toxicities. It is important to obtain reliable information on arsenic speciation for understanding toxicity and relevant modes of action. Currently, popular arsenic speciation techniques, such as chromatographic/electrophoretic separation following extraction of biological samples, may induce the alternation of arsenic species during sample preparation. The present study was aimed to develop novel arsenic speciation methods for biological matrices using surface-enhanced Raman spectroscopy (SERS), which, as a rapid and non-destructive photon scattering technique. The use of silver nanoparticles with different surface coating molecules as SERS substrates permits the measurement …

Development Of A Surface-Enhanced Raman Spectroscopy Method For The Detection Of Benzodiazepines In Urine, Erika L. Doctor

FIU Electronic Theses and Dissertations

Benzodiazepines are among the most prescribed compounds for anti-anxiety and are present in many toxicological screens. These drugs are also prominent in the commission of drug facilitated sexual assaults due their effects on the central nervous system. Due to their potency, a low dose of these compounds is often administered to victims; therefore, the target detection limit for these compounds in biological samples is 10 ng/mL. Currently these compounds are predominantly analyzed using immunoassay techniques; however more specific screening methods are needed.

The goal of this dissertation was to develop a rapid, specific screening technique for benzodiazepines in urine samples …