Award Date

12-15-2025

Degree Type

Thesis

Degree Name

Master of Science in Engineering (MSE)

Department

Electrical and Computer Engineering

First Committee Member

Shengjie Zhai

Second Committee Member

Biswajit Das

Third Committee Member

Mei Yang

Fourth Committee Member

Hui Zhao

Number of Pages

128

Abstract

Every second, human skin processes over one million sensory signals while maintaining properties such as electrical conductivity, mechanical adaptability, and regenerative capability that surpass all synthetic materials. Contemporary bioelectronic devices prove inadequate when contacting skin surfaces due to poor adhesion and electrical contact issues that prevent effective sensing. Despite advancements in wearable and bioelectronic technologies, current devices face major drawbacks when interfacing with human skin, particularly in maintaining firm adhesion, conformability, and low-noise electrical signal acquisition.

This research focuses on the development of a biomimetic hydrogel-based interface for bioelectronic sensing. Specifically, a hybrid hydrogel system composed of polydopamine (PDA)- doped polyacrylamide (PAM) was devised to mimic the functional characteristics of natural skin. Within this soft, hydrated matrix, various conductive and reinforcing dopants including iron oxide (Fe₃O₄) nanoparticles, graphene nanoplatelets (xGNP), and lithium chloride (LiCl) were incorporated in different combinations to tune the hydrogel’s conductivity, and mechanical integrity while strengthening bioelectrical performance and skin adhesion.

The synthesized hydrogel composites were characterized using a suite of physicochemical, mechanical, and electrical tests to evaluate adhesion performance, stretchability, biocompatibility, and signal fidelity. Results demonstrated that a formulation containing all three dopants (Fe₃O₄, xGNP, and LiCl) as the best-performing composition, achieving the most favorable balance. The results show that such a biomimetic hydrogel can enable more reliable long-term biosignal monitoring in applications such as wearable health devices, biomedical diagnostics, human–machine interfaces, and soft robotics.

Keywords

Bioelectronic Interfaces; Conductive Hydrogels; Electrophysiological Signal Acquisition; Nanocomposite Hydrogels; Polydopamine (PDA); Skin-Adhesive Sensors

Disciplines

Biomechanical Engineering | Biomedical | Biomedical Devices and Instrumentation | Electrical and Computer Engineering | Engineering Science and Materials | Materials Science and Engineering

File Format

PDF

File Size

7000 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

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