Development of photoelectrochemical methods for the detection of calprotectin based on nanocomposites prepared by one-step method

Gold nanoparticles(Au NPs)-sensitized tin dioxide(SnO2) semiconductor not only broadens the visible light absorption range of the material,but also easily forms a Schottky barrier at the heterogeneous interface,which effectively promotes the separation of photogenerated e-/h+ and improves the sensitivity of the sensor. This work explored the one-step synthesis method to prepare SnO2@Au NPs heterogeneous materials,which have high photoelectric conversion efficiency and show better photoelectric properties. Based on the uniformity and firmness of this nanocomposite,the recognition layer can be modified on its surface to construct a“sandwich”biosensor with a sandwich structure to realize the specific photoelectric determination of calprotectin(CP). The linear range is 0.01-20.00 μg·mL-1,the detection limit is as low as 3.2 ng·mL-1,and the specificity is good and stable. In addition,the sensor has also been successfully used to detect CP in actual blood samples and obtained a good recovery rate,which could realize rapid and non-invasive detection of CP.