Simultaneous Unlocking Optoelectronic and Interfacial Properties of C60 for Ultrasensitive Immunosensing by Coupling to Metal−Organic Framework

Due to exceptional electron-accepting ability, light-absorption and delocalized conjugated structure, buckminsterfullerene (C60) has attracted fascinating interests in the field of organic solar cells. However, poor delocalization and accumulation of electrons for pristine C60 in physiological aqueous solution and difficulties in conjugation with biomolecules limit its extended photovoltaic ap-plications in bioassay. Herein, we reported the non-covalent coupling of C60 to an electronically complementary porphyrin-derived metal-organic framework (PCN-224) with carboxyl-group terminals. Such assembly not only offered a friendly interface for biocon-jugation but also resulted in a long-range ordering C60@PCN-224 donor-acceptor system that demonstrated an unprecedented pho-tocurrent enhancement up to 10 times with respect to each component. As an example, by further cooperating with Nanobodies, the as-prepared C60@PCN-224 was applied to a photoelectrochemical (PEC) immunosensor for S100 calcium-binding protei...