Visible-light driven Photoelectrochemical Immunosensor Based on SnS2@mpg-C3N4 for Detection of Prostate Specific Antigen

Abstract

Herein, a novel label-free photoelectrochemical (PEC) immunosensor based on SnS2@mpg-C3N4 nanocomposite is fabricated for the detection of prostate specific antigen (PSA) in human serum. Firstly, mesoporous graphite-like carbon nitride (mpg-C3N4) with carboxyl groups is synthesized successfully which possesses high specific surface area and large pore volume. Then, SnS2 as a typical n-type semiconductor with weak photoelectric conversion capability is successfully loaded on carboxylated mpg-C3N4 to form a well-matched overlapping band-structure. The as-synthesized SnS2@mpg-C3N4 nanocomposite performs outstanding photocurrent response under visible-light irradiation due to low recombination rate of photoexcited electron-hole pairs, which is transcend than pure SnS2 or pure mpg-C3N4. It is worth noting that SnS2@mpg-C3N4 nanocomposite is firstly employed as the photoactive material in PEC immunosensor area. The concentration of PSA can be analyzed by the decrease in photocurrent resulted from increased steric hindrance of the immunocomplex. Under the optimal conditions, the developed PEC immunosensor displays a liner photocurrent response in the range of 50 fg·mL−1 ~ 10 ng·mL−1 with a low detection limit of 21 fg·mL−1. Furthermore, the fabricated immunosensor with satisfactory stability, reproducibility and selectivity provides a novel method for PSA determination in real sample analysis.

CuS nanoparticles anchored to g-C3N4 nanosheets for photothermal ablation of bacteria

“…During the past few years, many research groups have reported different types of heterojunction photocatalysts comprised of g-C 3 N 4 and metal oxides or sulphides showing improved photothermal conversion efficiencies when compared with their individual components. 32,[35][36][37][38][39] Inspired by the above efforts, we herein construct a selfassembled PTT agent, PEG-CuS@g-C 3 N 4 by a rapid and simple recrystallization growth which was schematically illustrated in Scheme 1. In this composite, CuS played a role in generating hyperthermia under the NIR irradiation.…”

Recent Progress in Biosensors for Detection of Tumor Biomarkers

“…In order to obtain higher PEC (photoelectrochemical) efficiency, Zhang et al developed a new type of label-free photoelectrochemical immunosensor based on SnS 2 @mpg-C 3 N 4 to detect PSA [ 53 ]. The linear detection range of the photoelectrochemical immunosensor was 50 fg/mL–10 ng/mL, and the detection limit was 21 fg/mL with high sensitivity.…”

Vertically oriented SnS2 on MoS2 nanosheets for high-photoresponsivity and fast-response self-powered photoelectrochemical photodetectors

“…Moreover, this PEC-type photodetector collects the electrons at the conductive substrate, and then the electrons go into the counter electrode (Pt foil) and are combined with H + in the electrolyte, thus producing hydrogen. The reported studies predict in theory that the conduction and valence band edges of SnS 2 and MoS 2 could straddle the electrochemical potentials for water splitting, 32,33 which are also desirable in PEC applications.…”