Life Sciences Commons^™

Development Of Electrochemical Aptamer-Based Sensors For Sensitive And Specific Detection Of Small-Molecule Targets, Yingzhu Liu

FIU Electronic Theses and Dissertations

Electrochemical aptamer-based (E-AB) sensors have been applied for diverse applications such as forensic science, pharmaceutical diagnostics, food safety, environmental monitoring, and personal medical care due to their rapid, accurate, and specific detection of analytes in complex samples. However, limited sensitivity and a lack of portable devices for point-of-care applications have greatly hindered the maturation of E-AB sensors from proof-of-concept designs to commercial systems. This dissertation describes several novel strategies to improve the sensitivities of E-AB sensors and fabricate portable paper-based devices to remedy these problems. We first detail the development of a novel approach to utilize a defined mixture of …

Exonuclease Digestion Assay For Streamlining Aptamer Characterization, Engineering, And Sensor Development, Juan Canoura

FIU Electronic Theses and Dissertations

Aptamers are DNA or RNA oligonucleotide-based bioreceptors isolated in vitro through the Systematic Evolution of Ligands by Exponential Enrichment. Given the ease with which a selection can be customized, aptamers can be evolved to function in nearly any chemical environment, making them tailormade for their final application. However, the post-SELEX characterization of the 100-1000’s aptamer candidates remains a significant bottleneck as there are no suitable techniques for high-throughput characterization of each candidate’s affinity/specificity. Moreover, the final aptamer must be engineered to possess signal reporting functionality; this is often done via trail-and-error truncation to yield a structure-switching aptamer. This dissertation describes …

The Utilization Of Volatile Organic Compounds And Human Leukocyte Antigen Genes For Ethnic-Specific Differentiation Within Target Populations, Alice Breia Boone

FIU Electronic Theses and Dissertations

Human scent has been previously defined as a complex mixture of volatile organic compounds (VOCs) detected in the headspace above a scent sample. Humans generate odor from several areas of the body including hair, mouth, hand, axillae, and foot. Due to the novelty of human scent research, human scent evidence has been undervalued in the court of law. However, this type of evidence has significant value when physical evidence is not available at crime scenes. To increase the individualization and differentiation power of human scent evidence, this study aimed to further investigate the identification of chemical signatures within axillae of …

An Investigation To Corroborate Volatile And Biological Profiles Of Human Odor For Forensic Subject Identification, Chantrell J.G. Frazier

FIU Electronic Theses and Dissertations

Hands are an integral part in transferring complex microbial communities to and from our surroundings. As a result, hands are significant in provenance investigations as specific microbiota can be deposited on everyday objects through touch interactions. Skin microbiome, including bacteria, fungi, and viruses, are unique to each person, and this ‘uniqueness’ can be exploited and applied to forensic identification. Skin microbiota and volatile organic compounds (VOCs) are closely related due to specific bacteria breaking down non-volatile organic compounds to volatile organic compounds that are characteristically present in human scent. However, analyses of microbiota from touch interactions have proven to be …

Development Of A Microwave-Based Dna Extraction Method To Increase The Success Of Direct And Rapid Pcr Technique, Fabiana Taglia

FIU Electronic Theses and Dissertations

The goal of this project was to develop a fast, microwave-based extraction technique that could be employed for direct and rapid DNA analysis. The hypothesis was that the use of a microwave could increase the yield of DNA by opening the cell membrane, rendering the DNA available without the use of any other chemical treatment, and improving results from very low quantity samples.

At present rapid human DNA analysis is mainly restricted to genotyping saliva and sometimes blood samples. We hypothesized that microwave processing could expand the types of samples assessable to these procedures and increase sensitivity.

There were two …