Investigation of Highly Sensitive ZnO Nanostructure-Based Biosensors for the Detection of Biomarkers in Human Sweat

Author

G. M. Mehedi Hossain, The University of Texas Rio Grande Valley

Date of Award

8-2025

Document Type

Thesis

Degree Name

Master of Science in Engineering (MSE)

Department

Electrical Engineering

First Advisor

Fahmida Alam

Second Advisor

Karen Lozano

Third Advisor

Nazmul Islam

Abstract

The increasing global prevalence of chronic diseases such as diabetes, cardiovascular conditions, and stress-related disorders has emphasized the urgent need for real-time, non-invasive diagnostic tools. This thesis presents the development of a flexible, sweat-based biosensing platform capable of detecting four clinically significant biomarkers: glucose, cortisol, C-reactive protein (CRP), and lactate using low-cost, nanomaterial-integrated electrochemical sensors. The central focus of the work is the synthesis and integration of zinc oxide (ZnO) nanostructures grown by sonochemical synthesis method, which offers advantages such as low-temperature processing, tunable morphology, and compatibility with flexible substrates like polyethylene terephthalate (PET). ZnO Nanostructures were fabricated on gold-coated PET substrates and subsequently functionalized with enzyme or antibody layers for selective detection of glucose, cortisol, and CRP. In addition, a graphene-based flexible lactate sensor was developed using laser-engraved electrodes and nanocomposite inks, extending the platform to a fourth analyte. To support portable and wearable deployment, a custom-built miniaturized potentiostat was designed using a modular op-amp-based analog front-end and BLE-enabled microcontroller. This device was fabricated on a compact PCB and integrated with a rechargeable power supply, wireless interface, and real-time mobile visualization platform. Together, this work demonstrates a comprehensive, low-cost, and scalable approach to multi-analyte, noninvasive biosensing using sweat as the sampling medium.

Comments

Copyright 2025 G. M. Mehedi Hossain. All Rights Reserved. https://proquest.com/docview/3253949262

Recommended Citation

Hossain, G. M. M. (2025). Investigation of highly sensitive ZnO nanostructure-based biosensors for the detection of biomarkers in human sweat [Master's thesis, The University of Texas Rio Grande Valley]. ScholarWorks @ UTRGV. https://scholarworks.utrgv.edu/etd/1751