Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Anal Chem. 2021 Jan 19;93(2):677-682. doi: 10.1021/acs.analchem.0c04248. Epub 2020 Dec 7.
A light source plays a pivotal role in a photofuel cell (PFC)-based self-powered biosensor. Although a visible light source has been extensively employed to drive a PFC, it still has some drawbacks for biosensing due to its relatively high energy. Herein we constructed a PFC-based aptasensor using near-infrared (NIR) light as the irradiation source. To achieve an efficient absorption of the NIR light, NaYF:Yb,Er upconversion nanoparticles (UCNPs) that could convert low-energy incident light into high-energy radiation were combined with BiS nanorods (UCNPs/BiS) to serve as the photoactive materials. The PFC was comprised of a UCNPs/BiS photoanode and a Pt cathode, which could generate electrical output under NIR light irradiation to provide the self-powered sensing signal without the supply from an external power source. The aflatoxin B1 (AFB1) binding aptamer was immobilized on the photoanode to serve as the recognition element. The detection of AFB1 was based on the competition between the interaction of aptamer with AFB1 analyte and the hybridization of aptamer with Au nanoparticles-labeled DNA sequence (AuNPs-cDNA). Under optimum conditions, the proposed aptasensor presented good sensitivity and high specificity for AFB1 detection in the concentration range from 0.01 to 100 ng·mL, with a detection limit of 7.9 pg·mL. Moreover, the developed sensor was applied to an assay of AFB1 in flour samples with a desirable accuracy and precision.
光源在基于光燃料电池（PFC）的自供电生物传感器中起着关键作用。尽管可见光光源已被广泛用于驱动 PFC，但由于其能量相对较高，对于生物传感仍存在一些缺点。在此，我们构建了一种基于近红外（NIR）光作为辐照源的 PFC 适体传感器。为了实现对 NIR 光的有效吸收，我们将能够将低能量入射光转化为高能辐射的 NaYF:Yb,Er 上转换纳米粒子（UCNPs）与 BiS 纳米棒（UCNPs/BiS）结合，用作光活性材料。PFC 由 UCNPs/BiS 光阳极和 Pt 阴极组成，可在 NIR 光照射下产生电输出，为自供电传感信号提供无需外部电源的支持。黄曲霉毒素 B1（AFB1）结合适体被固定在光阳极上作为识别元件。AFB1 的检测是基于适体与 AFB1 分析物相互作用与适体与 Au 纳米粒子标记的 DNA 序列（AuNPs-cDNA）杂交之间的竞争。在最佳条件下，该适体传感器在 0.01 至 100 ng·mL 的浓度范围内对 AFB1 表现出良好的灵敏度和特异性，检测限为 7.9 pg·mL。此外，该开发的传感器还应用于面粉样品中 AFB1 的测定，具有良好的准确性和精密度。
