Perylene Derivative Self-Assembly Material for Photoelectrochemical Biosensing

Screening highly efficient photoelectrochemical (PEC) materials such as organic semiconductors self-assembled by organic molecules was crucial for designing sensitive biosensors. The local chemical environment of an organic molecule, for example, a functional group, is a critical factor to be taken into account when improving the PEC properties. In this work, the functional group─anhydride, imide, and N -methylimide─on the 3, 4, 9, and 10 positions of the perylene core was used to create different chemical environments and investigate the PEC properties. The three perylene derivatives were 3,4,9,10-perylenetetracarboxylic dianhydride (PDA), 3,4,9,10-perylenetetracarboxylic diimide (PDI), and N, N ′-dimethyl-3,4,9,10-perylenedicarboximide (PDI-CH 3 ). They showed distinct photocurrent: PDI-CH 3 > PDA > PDI. The results were illustrated with the intermolecular distance of cofacial π–π stacking of the perylene plane and self-assembly structure, which was caused by their different functional group. In the presence of the electron donor ascorbic acid (AA), the photocurrent of PDI-CH 3 showed the largest enhancement among them. As a proof of concept, a self-powered PEC biosensor for alkaline phosphatase (ALP) detection using a PDI-CH 3 self-assembly material as the PEC platform was successfully constructed with the linear range from 0.1 to 400 U·L –1 . The PEC sensor showed good feasibility in a human serum sample.