在本研究中，我們圖案化的聚(3,4-乙烯基二氧噻吩):聚(苯乙烯磺酸)(PEDOT:PSS)薄膜上，深入探討無模板電化學聚合法以製備羥基官能化聚(3,4-乙烯基二氧噻吩)(PEDOT-OH)三維(3D)奈米結構，並開發出五種不同形態的奈米結構以作為有機電化學電晶體(OECT)的主動層通道。同時，我們進一步探索這些OECT的元件特性，並優化發展成生物感測器對人體汗液中壓力荷爾蒙之皮質醇(Cortisol)進行量化感測應用潛力評估。研究結果顯示，通過調整電聚合條件(如電解質配方、聚合時間及溫度)，可以成功製備出顆粒狀(Granular, G)、珊瑚狀(Coral-like, C)、管狀(Tubular, T)、珊瑚狀修飾的顆粒(GC)和珊瑚狀修飾的管狀(TC)等奈米結構，並設計成複合式OECT主動層通道。在研究中，我們不僅分析這些PEDOT-OH奈米結構的物理化學特性，還評估其在OECT中的元件特性差異，並進一步優化界面工程技術以實現Cortisol的高效量化感測。為了提升元件對Cortisol的感測靈敏度及專一性，研究導入多項表面工程技術，包括3-環氧丙氧丙基三甲氧基矽烷(GOPS)的氣相沉積、適體(Aptamer)的表面化學接枝、以及牛血清白蛋白(BSA)的非特異性封裝。研究結果證實，經奈米結構化及官能基化修飾的OECT元件，對於Cortisol的線性檢測範圍為1 pM至10 μM，涵蓋了人體汗液中Cortisol的分泌濃度範圍。該研究開發的元件具有極高的檢測穩定性，感測響應時間僅需20秒，並對於結構相似的干擾物展現卓越的選擇性。此外，本開發OECT元件的檢測極限可達到0.012 fM。綜合評估，此優化的3D-OECT元件可展現結合穿戴式醫療檢測的潛力，在未來能為個人化汗液醫療感測應用提供了極具前景的解決方案。

This study thoroughly investigated the template-free electrochemical polymerization methods for hydroxyl-functionalized poly(3,4-ethylenedioxythiophene) (PEDOT-OH) nanostructures. Using the pre-patterned poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) films, we fabricated five distinct nanostructures to serve as the decorated layers on the active-layer channels in organic electrochemical transistors (OECTs) for sweat detection applications. Furthermore, we explored the characteristics of these OECT devices and optimized them for potential application as biosensors for detecting cortisol, a stress hormone present in human sweat. The results demonstrated that by tailoring the polymerization conditions, such as electrolyte composition, polymerization time, and temperature, we successfully synthesized granular (G), coral-like (C), tubular (T), granular-decorated coral-like (GC), and tubular-decorated coral-like (TC) nanostructures. These were then designed ab the hybrid OECT active-layer channels. Additionally, we not only analyzed the physicochemical properties of these PEDOT-OH nanostructures but also evaluated their performance in OECT devices. We then optimized interfacial engineering techniques to enable OECTs for efficient quantitative sensing of cortisol. To enhance the sensitivity and specificity of the OECTs for cortisol detection, multiple surface engineering techniques were employed, including vapor deposition of 3-glycidyloxypropyltrimethoxysilane (GOPS), aptamer-based surface chemical grafting, and nonspecific blocking with bovine serum albumin (BSA). The results confirmed that the OECT devices, modified with nanostructures and functionalized interfaces, achieved a linear detection range of 1 pM to 10 μM, encompassing the physiological cortisol concentrations found in human sweat. The devices demonstrated high detection stability, with a response time of just 20 seconds, and exceptional selectivity against structurally similar interferents. Moreover, the OECT devices achieved an impressive detection limit (LOD) of 0.012 fM. Overall, the developed 3D-OECT devices exhibit significant potential for integration with wearable biomedical sensors, providing a promising solution for personalized sweat-based healthcare monitoring applications.

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