Photoelectrochemical thrombin biosensor based on perylene-3,4,9,10-tetracarboxylic acid and Au co-functionalized ZnO nanorods with signal-off quenching effect of Ag@Ag2S

Highly efficient photoelectrochemical aptasensor based on CdS/CdTe QDs co-sensitized TiO2 nanoparticles designed for thrombin detection

A photoelectrochemical (PEC) sensor for the sensitive detection of thrombin (TB) was established. Co-sensitized combination of TiO2 nanoparticles combined with modified cadmium sulfide and cadmium telluride quantum dots (CdS/CdTe QDs) was utilized as a photoactive material. Successful growth of CdS/CdTe quantum dots on mesoporous TiO2 films occured by successive ion-layer adsorption and reaction. This interesting formation of co-sensitive structure is conducive to enhancing the photocurrent response by improving the use rate of light energy. Additionally, the step-level structure of CdS/CdTe QDs and TiO2 NPs shows a wide range of visible light absorption, facilitating the dissociation of excitons into free electrons and holes. Consequently, the photoelectric response of the PEC analysis platform is significantly enhanced. This constructed PEC aptasensor shows good detection of thrombin with a low detection limit (0.033 pM) and a wide linear range (0.0001-100 nM) in diluted actual human serum samples. In addition, this PEC aptasensor also has the characteristics of good stability and good reproducibility, which provides a novel insight for the quantitative measurement of other similar analytes.

High-performance Vo-ZnO/ZnS benefiting nanoarchitectonics from the synergism between defect engineering and surface engineering for photoelectrochemical glucose sensors

In this study, a ZnO/ZnS nanocluster heterojunction photoelectrode rich in surface oxygen defects (Vo-ZnO/ZnS) was prepared by applying a simple in situ anion substitution and nitrogen atmosphere annealing method. The synergism between defect and surface engineering significantly improved the photocatalysts. Given this synergism, Vo-ZnO/ZnS was endowed with a long carrier lifetime, narrow band gap, high carrier density, and high performance toward electron transfer under light conditions. Thus, Vo-ZnO/ZnS had three times the photocurrent density of ZnO under light illumination. To further evaluate its advantages in the field of photoelectric bioassay, Vo-ZnO/ZnS was applied as the photocathode of photoelectric sensor system for glucose detection. Vo-ZnO/ZnS showed excellent performance in glucose detection in various aspects, including a low detection limit, high detection sensitivity, and a wide detection range.