Dual-mode self-powered photoelectrochemical and colorimetric determination of procalcitonin accomplished by multienzyme-expressed Ni4Cu2 bimetallic hollow nanospheres and spherical nanoflower-MoS2/Cu2ZnSnS4/Bi2S3

Abstract

Bacterial infections, viral infections and autoimmune diseases pose a considerable threat to human health. Procalcitonin (PCT) has emerged as a biomarker for the detection of these diseases. To ensure accurate and reliable results, we propose a dual-mode approach that incorporates self-validation and self-correction mechanisms. Herein, we develop a dual-mode self-powered photoelectrochemical (PEC) and colorimetric sensor to determine PCT. The self-powered PEC sensor was constructed with a photoanode of spherical nanoflower-MoS₂/Cu₂ZnSnS₄/Bi₂S₃ material and a photocathode of CuInS₂ material. Ni₄Cu₂ bimetallic hollow nanospheres (BHNs) possess superoxide dismutase and catalase performance, which facilitate superoxide anion radical (·O₂^-) and H₂O₂ circulating generation, promoting the separation of photogenerated electrons and holes to amplify photocurrent signal. Thus Ni₄Cu₂ BHNs is used as a marker material for PEC sensor. Meanwhile, in colorimetric mode, Ni₄Cu₂ BHNs converts blue oxTMB to a colourless TMB for colorimetric detection of PCT. Based on this principle, dual-mode determination of PCT with high sensitivity is achieved. The dual-mode method not only demonstrates outstanding properties and practicability, but also presents an effective, highly efficient and reliable method for detecting PCT.

Keywords: Colorimetric method; CuInS(2); Ni(4)Cu(2) BHNs; PEC sensor; Type-II SNF–MoS(2)/ CZTS/Bi(2)S(3).