Biosensor Research Team, Electronics and Telecommunications Research Institute, 218 Gajeong-ro, Yuseong-gu, Daejeon 305-700, Republic of Korea.
Biosens Bioelectron. 2012 Mar 15;33(1):233-40. doi: 10.1016/j.bios.2012.01.010. Epub 2012 Jan 17.
This paper describes a new technique for the detection of uncharged or feebly charged small molecules (<400Da) using Si field-effect transistor (FET) biosensors that are signal-enhanced by gold nanoparticle (NP) charges under dry measurement conditions. NP charges are quickly induced by a chemical deposition (that is, Au deposition) and the indirect competitive immunogold assay, and strongly enhance the electrical signals of the FET biosensors. For the validation of signal enhancement of FET biosensors based on NP charges and detection of uncharged or feebly charged small molecules, mycotoxins (MTXs) of aflatoxin-B1 (AFB1), zearalenone (ZEN), and ochratoxin-A (OTA) were used as target molecules. According to our experimental results, the signal is 100 times more enhanced than the use of the existing solution FET biosensing techniques. Furthermore, this method enables the FET biosensor to quantitatively detect target molecules, regardless of the ionic strengths, isoelectric points (pI), or pHs of the measured sample solutions.
本文介绍了一种新的技术，用于检测不带电荷或电荷微弱的小分子（<400Da），使用的是在干燥测量条件下通过金纳米粒子（NP）电荷增强的 Si 场效应晶体管（FET）生物传感器。NP 电荷可通过化学沉积（即 Au 沉积）和间接竞争免疫金测定快速诱导，并强烈增强 FET 生物传感器的电信号。为了验证基于 NP 电荷的 FET 生物传感器信号增强和检测不带电荷或电荷微弱的小分子的能力，本文选择了黄曲霉毒素 B1（AFB1）、玉米赤霉烯酮（ZEN）和赭曲霉毒素 A（OTA）等真菌毒素作为目标分子。根据我们的实验结果，与使用现有溶液 FET 生物传感技术相比，信号增强了 100 倍。此外，该方法使 FET 生物传感器能够定量检测目标分子，而不受测量样品溶液的离子强度、等电点（pI）或 pH 值的影响。
