Keywords

Electrochemical Biological Impedance Spectroscopy, Bacterial Stencil Mask Microenvironment, Antibiotic Testing, Gram Negative Bacteria, Xurography

Abstract

With the increasing incidence of diverse global bacterial outbreaks, establishing an immutable, decentralized database that can track regional changes in bacterial resistance with time is crucial. In this work, we present a biosystems approach to tackle this problem, utilizing two novel in vitro bacterial assays: 1) Minimum Inhibitory Concentration Test (MIC) built using Kapton® stencil masks for localized microenvironments, 2) Electrochemical Biological Impedance Spectroscopy (EBIS) devices microfabricated using laser ablation on metalized 3D printed substrates, for enhanced resolution of interdigitated electrode (IDE) characteristics. Using our IDE method, we successfully recorded four parameters of bacterial biofilm growth, separating bacterial species at the 9.77 kHz frequency point at the 2- and 8-hour time points. When testing antibiotic susceptibility with kanamycin, oxytetracycline, penicillin G, and streptomycin, the MICs showed an increase in inhibition size with increased dose efficiency, corresponding to logarithmic and polynomial equations. Additionally, a Caspio database was developed with the data collected from the two key assays. The variations in these microbiological assays proved to be searchable using this query-enabled database, demonstrating that this biosystems technology has the potential to become a widely used tool in bacterial exploration, being of huge value extending to pharmaceuticals, biotechnology, food industries, and microbial conservation.

Completion Date

2024

Semester

Spring

Committee Chair

Rajaraman, Swaminathan

Degree

Doctor of Philosophy (Ph.D.)

College

College of Engineering and Computer Science

Department

Material Science and Engineering

Degree Program

Material Science and Engineering

Format

application/pdf

Language

English

Rights

In copyright

Release Date

November 2025

Length of Campus-only Access

1 year

Access Status

Doctoral Dissertation (Campus-only Access)

Campus Location

Orlando (Main) Campus

Accessibility Status

Meets minimum standards for ETDs/HUTs

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Restricted to the UCF community until November 2025; it will then be open access.

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