Department of Electronic Materials Engineering, Kwangwoon University, Gwangun-ro 20, Nowon-gu, Seoul 01897, Republic of Korea.
Biosensors (Basel). 2024 Mar 13;14(3):141. doi: 10.3390/bios14030141.
Bovine serum albumin (BSA) is commonly incorporated in vaccines to improve stability. However, owing to potential allergic reactions in humans, the World Health Organization (WHO) mandates strict adherence to a BSA limit (≤50 ng/vaccine). BSA detection with conventional techniques is time-consuming and requires specialized equipment. Efficient alternatives such as the ion-sensitive field-effect transistor (ISFET), despite rapid detection, affordability, and portability, do not detect BSA at low concentrations because of inherent sensitivity limitations. This study proposes a silicon-on-insulator (SOI) substrate-based dual-gate (DG) ISFET platform to overcome these limitations. The capacitive coupling DG structure significantly enhances sensitivity without requiring external circuits, owing to its inherent amplification effect. The extended-gate (EG) structure separates the transducer unit for electrical signal processing from the sensing unit for biological detection, preventing chemical damage to the transducer, accommodating a variety of biological analytes, and affording easy replaceability. Vapor-phase surface treatment with (3-Aminopropyl) triethoxysilane (APTES) and the incorporation of a SnO sensing membrane ensure high BSA detection efficiency and sensitivity (144.19 mV/log [BSA]). This DG-FET-based biosensor possesses a simple structure and detects BSA at low concentrations rapidly. Envisioned as an effective on-site diagnostic tool for various analytes including BSA, this platform addresses prior limitations in biosensing and shows promise for practical applications.
牛血清白蛋白（BSA）通常被纳入疫苗中以提高稳定性。然而，由于人类潜在的过敏反应，世界卫生组织（WHO）要求严格遵守 BSA 限制（≤50ng/疫苗）。传统技术检测 BSA 既费时又需要专门的设备。尽管离子敏感场效应晶体管（ISFET）等高效替代品具有快速检测、经济实惠和便携性等优点，但由于固有灵敏度限制，无法检测低浓度的 BSA。本研究提出了一种基于绝缘体上硅（SOI）基底的双栅（DG）ISFET 平台，以克服这些限制。电容耦合 DG 结构具有固有放大效应，无需外部电路即可显著提高灵敏度。扩展栅（EG）结构将用于电信号处理的换能器单元与用于生物检测的传感单元分离，防止换能器受到化学损伤，容纳各种生物分析物，并易于更换。采用（3-氨丙基）三乙氧基硅烷（APTES）的气相表面处理和 SnO 传感膜的结合，确保了高 BSA 检测效率和灵敏度（144.19 mV/log [BSA]）。这种基于 DG-FET 的生物传感器结构简单，能够快速检测低浓度的 BSA。该平台有望成为包括 BSA 在内的各种分析物的有效现场诊断工具，解决了生物传感中的先前限制问题，并具有实际应用的潜力。
