A novel photoelectrochemical singal amplification assay for procalcitonin detection based on ZnxBi2S3+x sensitized NiTiO3 matrix

Abstract

Abstract An original signal amplification photoelectrochemical (PEC) immunosensor for procalcitonin detection was fabricated based on ZnxBi2S3+x sensitized NiTiO3 nanorods. Using ethylene glycol as medium, the NiTiO3 nanorods were successfully manufactured after calcination in air atmosphere, the rod-like structure have rough surface that produced benefit to capture lots of functional ZnxBi2S3+x, the sensitizer sensitized NiTiO3 on ITO substrate by means of a sequential ionic layer adsorption reaction, and the obtained ZnxBi2S3+x/NiTiO3 composites showed an excellent absorption of visible light owing to the matched band gap. By the way, ZnxBi2S3+x/NiTiO3 composites as mimic enzyme of glucose oxidase, high sensitivity was achieved due to the generated H2O2 as holes scavenger when glucose added, that promote the photo electrons transfer quickly, further increased the PEC signal. The as prepared sensor showed a large linear range of 0.0001–50\u2009ng·mL−1 with 0.04\u2009pg·mL−1 detection limit. Simultaneously, the signal amplification strategy of this sensor provides applicable to other PEC immunosensors for detection of other targets.