Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Entire DC Network

Analysis Of Polycyclic Aromatic Hydrocarbons In Tobacco Related Samples Via High Performance Liquid Chromatography And Laser Excited Time Resolved Shpol' Skii Spectroscopy, Ahmed Comas Jan 2023

Analysis Of Polycyclic Aromatic Hydrocarbons In Tobacco Related Samples Via High Performance Liquid Chromatography And Laser Excited Time Resolved Shpol' Skii Spectroscopy, Ahmed Comas

Electronic Theses and Dissertations, 2020-2023

Human exposure to polycyclic aromatic hydrocarbons (PAHs) due to cigarette smoke is well known. It is also known that PAHs are not inherent components of tobacco. Their presence in cigarette smoke results from the curing process of tobacco leaves used for the fabrication of cigarettes and the incomplete combustion of tobacco during the smoking process. The two chromatographic versions of EPA method 610 are popular approaches for the analysis of PAHs in a wide variety of samples. This method, which is based either on High-Performance Liquid-Chromatography (HPLC) or Gas-Chromatography (GC) has shown the presence of Benzo[a]pyrene (B[a]P) in tobacco samples …


Analysis Of Multi-Drug Resistant Mycobacterium Tuberculosis Using Split Deoxyribozymes, Abryana Fergus Jan 2023

Analysis Of Multi-Drug Resistant Mycobacterium Tuberculosis Using Split Deoxyribozymes, Abryana Fergus

Electronic Theses and Dissertations, 2020-2023

Globally, tuberculosis, a disease caused by the species of Mycobacterium tuberculosis (Mtb) complex, stands as a leading cause of death from a single infectious agent. Even though antituberculous drugs are available, treatment is challenging due to antibiotic resistance associated with point mutations in the bacterial genome. Resistance to the first-line antibiotics – rifampin and isoniazid – results in multidrug-resistant tuberculosis (MDR) requiring a more complicated treatment regimen. Timely and accurate identification of drug-resistant TB cases can help prescribe the most effective treatment and prevent the spread of infection. This research aims to develop an assay to discern multi-drug resistant forms …


A Developmental Investigation Of Separation And Analysis Of Molecular Mass 302 Da Polyaromatic Hydrocarbons Using High Performance Liquid Chromatography And Chiral Stationary Phase, James Janesko Jan 2023

A Developmental Investigation Of Separation And Analysis Of Molecular Mass 302 Da Polyaromatic Hydrocarbons Using High Performance Liquid Chromatography And Chiral Stationary Phase, James Janesko

Electronic Theses and Dissertations, 2020-2023

High molecular weight – polycyclic aromatic hydrocarbons (HMW-PAH) are often found where air, water, and soil are subject to higher levels of industrial pollutants. These molecules are environmentally concerning due to their carcinogenic, mutagenic, and tumorigenic propensities. Furthermore, the isomers in this family are challenging to separate due to similar retention parameters, spectroscopic fingerprints, and mass spectral patterns. The primary purpose of this dissertation is to expand on the methodology for separation and analysis of the molecular mass 302 Da six-ring isomers using High Performance Liquid Chromatography. Retention behaviors of 21 commercially available isomers in synthetic mixture were collected via …


Error Rate Determination Of Latent Print Chemistry Via 1d And 2d Gas Chromatography, Jessica Kindell Jan 2023

Error Rate Determination Of Latent Print Chemistry Via 1d And 2d Gas Chromatography, Jessica Kindell

Electronic Theses and Dissertations, 2020-2023

Latent print evidence collected from crime scenes are analyzed and compared by examiners using the ACE-V protocol (Analysis, Comparison, Evaluation-Verification) to identify potential suspects. However, smudged and poor-quality prints, usually deemed inconclusive, could be utilized for source association or discrimination based on the chemistry of the oils and sweat that comprises the latent print residue (LPR). For this research, LPRs were collected from various places on the face and analyzed via two-dimensional gas chromatography-mass spectrometry (2D GC-MS), one-dimensional (1D) GC-MS, and direct analysis in real time-high resolution mass spectrometry (DART-HRMS). LPR recovery with two common sample preparation methods, derivatization and …


Instrumental Approaches For High Resolution Photoluminescence Spectroscopy And Its Applications To Environmental Analysis, Anthony Santana Jan 2023

Instrumental Approaches For High Resolution Photoluminescence Spectroscopy And Its Applications To Environmental Analysis, Anthony Santana

Electronic Theses and Dissertations, 2020-2023

Photoluminescence phenomena provide valuable information for the direct analysis of target chemicals in complex samples. To take full advantage of the information content of fluorescence and phosphorescence phenomena, the analyst should have access to instrumentation capable to record data formats in the wavelength and time domains. Previous efforts in our lab have developed laser-based instrumentation to combine spectral and lifetime information into data formats known as wavelength time matrices (WTMs) and time-resolved excitation emission matrices (TREEMs). Recording WTMs during the emission decay of the sample makes it possible to unambiguously identify chemicals on the bases of spectral and lifetime information. …


Using Wastewater-Based Epidemiology To Study Chlamydia Occurrence On A College Campus, Jessie E. Chin Quee Jan 2023

Using Wastewater-Based Epidemiology To Study Chlamydia Occurrence On A College Campus, Jessie E. Chin Quee

Honors Undergraduate Theses

Chlamydia is a sexually transmitted disease caused by Chlamydia trachomatis, commonly affecting sexually active college-aged adults. Presently, opportunistic testing, self-testing, and information campaigns are methods to screen vulnerable populations and raise awareness about chlamydia. Chlamydia remains underdiagnosed and undertested due to a lack of participation by individuals who may have been exposed to it. Wastewater-based epidemiology is a rising biomonitoring tool that detects the presence of disease- and drug-specific biomarkers in a community's wastewater. In this study, wastewater-based epidemiology was used to detect the presence of C. trachomatis on the University of Central Florida campus. Wastewater samples were collected …


Development Of A Screening Methodology For The Analysis Of Rhodamine B In Foodstuffs, George T. Knecht Jan 2023

Development Of A Screening Methodology For The Analysis Of Rhodamine B In Foodstuffs, George T. Knecht

Honors Undergraduate Theses

Synthetic dyes that are used as color additives in foodstuffs are regulated by the Food and Drug Administration (FDA) under the Food, Drug, and Cosmetic Act (FD&C). The use of synthetic dyes not approved by the FDA, or the addition of dyes approved by the FDA above their maximum concentration limits in foodstuffs necessarily constitutes illegal food adulteration. Recently, rhodamine B (RhB), a bright-pink synthetic dye not approved for use in foodstuffs, has become an adulterant of interest due to its discovery in a large variety of food samples, and its identity as a potential carcinogen. Numerous chromatographic and spectroscopic …


Split Catalytic Probes For The Detection Of Monkeypox Virus, Jaehyun Ahn Jan 2023

Split Catalytic Probes For The Detection Of Monkeypox Virus, Jaehyun Ahn

Honors Undergraduate Theses

The COVID-19 outbreak highlighted the important role that diagnostic tests play in the healthcare system. To reduce the impact of infectious disease outbreaks, the development of rapid and cost-effective point-of-care-tests (POCTs) is crucial. With the dissemination of the Monkeypox (Mpox) virus, it became a necessity to produce POCTS that are inexpensive and easy to use. This work explored the construction of two colorimetric assays that aim to detect Mpox genetic signatures. One is based on the split-peroxidase-like deoxyribozyme probes (sPDz), while the other utilizes a cascade system of split RNA-cleaving deoxyribozyme (sDz) and peroxidase-like deoxyribozyme (PDz). Both rely on catalytic …