Biomaterial-based dry electrodes to improve EEG signal quality

This study investigates the development of soft, biomaterial-based dry electrodes aimed at improving the quality of Electroencephalography (EEG) signal acquisition while ensuring enhanced wearer comfort. A comprehensive review of recent research demonstrates that biomaterial-derived dry electrodes exhibit notably lower skin-electrode impedance, greater signal stability, and diminished susceptibility to motion artifacts compared to conventional alternatives. Their inherent flexibility and microstructured surface topology promote superior skin conformity, thereby enabling signal recordings comparable to those obtained with standard gel electrodes. Furthermore, the mechanical resilience and biocompatibility of these polymer systems reinforce their suitability for integration into clinical and long-term monitoring frameworks. Overall, the presented findings underscore the promising potential of polymeric dry electrodes as a reliable, durable, and user-friendly solution for continuous EEG applications. Electroencephalography remains one of the most extensively applied noninvasive approaches for assessing cerebral electrical activity, particularly in clinical diagnostics and neuroscience research. Despite their widespread use, conventional wet electrodes are associated with several inherent drawbacks, including skin irritation, potential allergic responses, and reduced stability during prolonged recordings. These limitations have led to a growing focus on alternative electrode technologies, particularly dry electrodes. By eliminating the need for conductive gel, dry electrodes simplify the setup process and enhance user comfort, thereby offering greater practicality for continuous and long-term health monitoring under real-world conditions [۱,۲]. Biomaterial-based dry electrodes present substantial advantages over their traditional counterparts. Specifically, flexible polymer matrices, such as polydimethylsiloxane (PDMS) and organic conductive films, facilitate superior skin conformity, thereby maximizing the contact area and mitigating signal artifacts. Furthermore, the strategic incorporation of nanomaterials including MXene nanosheets, carbon nanotubes, and graphene flakes-significantly enhances electrical conductivity. By integrating breakthroughs in materials science and biocompatible engineering, these advanced electrodes are positioned to effectively bridge the functional gap between conventional gel-based systems and practical, dry monitoring solutions [۲,۴,۵]. A systematic search of leading electronic databases was executed employing the predefined set of keywords. The scope of this literature review was intentionally restricted to articles published in the English language within the preceding fifteen years. Relevant data points-specifically the materials employed, the electrode architectural designs, and the reported outcomes pertaining to EEG signal quality-were subsequently extracted for analysis. Mechanical assessments validated the electrodes' substantial flexibility and mechanical resilience, confirming their suitability for protracted wearable monitoring. Furthermore, surface micro-texturing proved highly effective in suppressing motion-induced artifacts, particularly during dynamic facial movements. Following optimization of the polymer formulation, the measured skin-electrode impedance was found to be approximately ten times that of standard gel electrodes. Crucially, these biomaterial-based dry electrodes successfully captured high-fidelity resting-state alpha rhythms and event-related potentials (e.g., P۳۰۰) that were practically indistinguishable from those recorded by gel- based references. Subjective feedback also corroborated superior participant comfort throughout extended recording periods. Collectively, these findings establish these novel devices as a reliably comfortable and high-performance alternative to conventional EEG instrumentation [۲,۳]. The realization of this soft polymer-based dry electrode configuration effectively addresses several intrinsic limitations associated with conventional EEG measurement systems. These devices consistently yield high signal fidelity, maintain a significantly reduced skin-electrode impedance profile, and exhibit robust operational stability. These outcomes are consistent with prior literature advocating for such designs as viable counterparts to gel-based systems, crucially omitting their inherent disadvantages. Nevertheless, future research efforts must prioritize validating Metallurgy and Materials Engineering ۱۶ & ۱۷ December ۲۰۲۵ Tehran انجمن یادگری ایران ددانشگاهی مهندسی مواد و متالورژی ایران ۲۵ و ۲۶ آذرماه ۱۴۰۴ / تهران the efficacy of these electrodes across diverse and larger subject cohorts to definitively establish their broad applicability within routine EEG procedures [۱,۴].

کلیدواژه ها:

Biomaterials ، Electroencephalography ، Dry EEG electrodes ، Long-term monitoring