Tong Jing, Zhang Peng, Zhang Lei, Zhang Dongwei, Beratan David N, Song Haifeng, Wang Yi, Li Tie
Science and Technology on Microsytem Laboratory, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
University of Chinese Academy of Sciences (UCAS), Beijing 100049, China.
Sens Actuators B Chem. 2020 May 1;310. doi: 10.1016/j.snb.2020.127838. Epub 2020 Feb 6.
Photosensitive proteins are naturally evolved photosensors that often respond to light signals of specific wavelengths. However, their poor stability under ambient conditions hinders their applications in non-biological settings. In this proof-of-principle study, we grafted the blue light using flavin (BLUF) protein reconstructed with flavin adenine dinucleotide (FAD) or roseoflavin (RoF) onto pristine graphene, and achieved selective sensitivity at 450 nm or 500 nm, respectively. We improved the thermal and operational stability substantially via structure-guided cross-linking, achieving 6-month stability under ambient condition and normal operation at temperatures up to 200 °C. Furthermore, the device exhibited rare negative photoconductivity behavior. The origins of this negative photoconductivity behavior were elucidated via a combination of experimental and theoretical analysis. In the photoelectric conversion studies, holes from photoexcited flavin migrated to graphene and recombined with electrons. The device allows facile modulation and detection of charge transfer, and provides a versatile platform for future studies of photoinduced charge transfer in biosensors as well as the development of stable wavelength-selective biophotosensors.
光敏蛋白是自然进化的光传感器，通常对特定波长的光信号作出反应。然而，它们在环境条件下稳定性较差，这阻碍了它们在非生物环境中的应用。在这项原理验证研究中，我们将用黄素腺嘌呤二核苷酸（FAD）或玫红菌素（RoF）重构的蓝光利用黄素（BLUF）蛋白接枝到原始石墨烯上，分别在450纳米或500纳米处实现了选择性灵敏度。我们通过结构导向交联大幅提高了热稳定性和操作稳定性，在环境条件下实现了6个月的稳定性，在高达200℃的温度下能正常运行。此外，该器件表现出罕见的负光电导行为。通过实验和理论分析相结合的方式阐明了这种负光电导行为的起源。在光电转换研究中，光激发黄素产生的空穴迁移到石墨烯上并与电子复合。该器件能够轻松调制和检测电荷转移，并为未来生物传感器中光诱导电荷转移的研究以及稳定的波长选择性生物光传感器的开发提供了一个通用平台。
