Development of photoelectrochemical immunosensor based on halide perovskite protected by organometallic compounds for determining interleukin-17A (IL-17A).

The overexpression of interleukin-17A (IL-17A) is closely associated with the pathogenesis of autoimmune diseases and cancer, rendering precise identification of IL-17A level critical for disease diagnosis and prognosis monitoring. In this study, CsPbBr nanoclusters (NCs) were embedded in CHBrOPb organometallic compound (Pb-MA MOC) via a hot injection approach. Through this way, the issue of CsPbBr NCs susceptible to decomposition in water was solved, and the photocurrent intensity that is generated by CsPbBr was significantly enhanced. A highly sensitive photoelectrochemical (PEC) sensor for detecting IL-17A in human serum was developed using CsPbBr/Pb-MA as the photoactive material. The electrode was initially modified with CsPbBr/Pb-MA. Then, antibody-modified FeO magnetic nanoparticles (MNs) with target analyte IL-17A captured, and IL-17A antibody-modified Au@CuNi diatomic catalyst (DAC) formed sandwich immune complex structure on the electrode. The existence of CuNi DAC led to a substantial reduction in photoelectric signal intensity due to oxidation of ascorbic acid in the supporting electrolyte. The photocurrent intensity exhibited linear correlation with IL-17A concentration within the range 15-750 pg/mL, and achieving an impressive detection limit of 1 pg/mL. Moreover, the sensor was successfully applied to the determination of IL-17A in human serum, suggesting its potential clinical applications.