A novel approach to photoelectrochemical immunoassay for procalcitonin on the basis of SnS2/CdS

Abstract

A label-free photoelectrochemical (PEC) immunoassay system based on the one-step synthesis of SnS₂/CdS nanocomposites is successfully constructed for sensitively analyzing procalcitonin (PCT). The one-step synthesis of SnS₂/CdS enables the rapid construction of an immunoassay system and avoids the waste of energy. In the constructed immunoassay system, CdS as a sensitizer for PCT analysis not only enhances the light absorption of SnS₂ as a photocurrent generator but also can accelerate the separation of photosensitive electrons and holes by forming a heterostructure. Under optimum conditions, the energy-saving assay platform based on the enhancement photocurrent response of SnS₂/CdS nanocomposites exhibited an excellent performance in analyzing a series of PCTs with different concentrations in a wide linear range of 0.5 pg mL⁻¹ to 100 ng mL⁻¹ and the detection limit was 0.17 pg mL⁻¹. In view of the advantages of good selectivity, high sensitivity, and facile preparation procedure, the PEC immunoassay is expected to be a promising analytical platform for rapid analysis of PCT and other biomarkers in clinical medical samples.