Anderson Grace I, Agee Alec A, Furst Ariel L
Department of Chemical Engineering, Massachusetts Institute of Technology Cambridge MA 02139 USA
Center for Environmental Health Sciences, Massachusetts Institute of Technology Cambridge MA 02139 USA.
Mater Adv. 2024 Aug 6;5(17):6813-6819. doi: 10.1039/d4ma00558a. eCollection 2024 Aug 27.
Understanding electron transport with electroactive microbes is key to engineering effective and scalable bio-electrochemical technologies. Much of this electron transfer occurs through small-molecule flavin mediators that perform one-electron transfers in abiotic systems but concerted two-electron transfer in biological systems, rendering abiotic systems less efficient. To boost efficiency, the principles guiding flavin electron transfer must be elucidated, necessitating a tunable system. Ionic liquids (ILs) offer such a platform due to their chemical diversity. In particular, imidazolium-containing ILs that resemble the amino acid histidine are bio-similar electrolytes that enable the study of flavin electron transfer. Using the model IL 1-ethyl-3-methylimidazolium ([Emim][BF]), we observe concerted two-electron transfer between flavin mononucleotide and an unmodified glassy carbon electrode surface, while a one-electron transfer occurs in standard inorganic electrolytes. This work demonstrates the power of ILs to enable the mechanistic study of biological electron transfer, providing critical guidelines for improving electrochemical technologies based on these biological properties.
了解电活性微生物的电子传递是设计有效且可扩展的生物电化学技术的关键。这种电子转移大多通过小分子黄素介导剂进行，这些介导剂在非生物系统中进行单电子转移，但在生物系统中进行协同双电子转移，这使得非生物系统效率较低。为提高效率，必须阐明指导黄素电子转移的原理，这需要一个可调谐系统。离子液体（ILs）因其化学多样性提供了这样一个平台。特别是，类似于氨基酸组氨酸的含咪唑鎓离子液体是生物相似电解质，能够用于研究黄素电子转移。使用模型离子液体1-乙基-3-甲基咪唑鎓（[Emim][BF]），我们观察到黄素单核苷酸与未修饰的玻碳电极表面之间发生协同双电子转移，而在标准无机电解质中发生单电子转移。这项工作展示了离子液体在生物电子转移机理研究方面的作用，为基于这些生物学特性改进电化学技术提供了关键指导。
