Ultrasensitive Photoelectrochemical Immunoassay Strategy Based on Bi2S3/Ag2S for the Detection of the Inflammation Marker Procalcitonin

Abstract

As an inflammatory marker, procalcitonin (PCT) is more representative than other traditional inflammatory markers. In this work, a highly efficient photoelectrochemical (PEC) immunosensor was constructed based on the photoactive material Bi2S3/Ag2S to realize the sensitive detection of PCT. Bi2S3 was prepared by a hydrothermal method, and Ag2S quantum dots were deposited on the ITO/Bi2S3 surface via in situ reduction. Bi2S3 is a kind of admirable photoelectric semiconductor nanomaterial on account of its moderate bandgap width and low binding rate of photogenerated electron holes, which can effectively convert light energy into electrical energy. Therefore, based on the energy level matching principle of Bi2S3 and Ag2S, a labeled Bi2S3/Ag2S PEC immunosensor was constructed, and the sensitive detection of PCT was successfully established. The linear detection range of the PEC immunosensor was 0.50 pg∙mL−1 to 50 ng∙mL−1, and the minimum detection limit was 0.18 pg∙mL−1. Compared with the traditional PEC strategy, the proposed PEC immunosensor is simple, convenient, and has good anti-interference, sensitivity, and specificity, which could provide a meaningful theoretical basis and reference value for the clinical detection of PCT.

A Novel Ratiometric Photoelectrochemical Biosensor Based on Front and Back Illumination for Sensitive and Accurate Glutathione Sensing

“…Therefore, the influence of mTiO 2 /Ag 2 S heterojunction formation on the photoelectric performance was investigated. The UV-visible absorption spectra in Figure 2 a depict the light-capturing abilities of Ag 2 S, mTiO 2 and mTiO 2 /Ag 2 S. It can be observed that TiO 2 exhibits significant absorption capability in the ultraviolet region, with an absorption edge at approximately 390 nanometers, while Ag 2 S demonstrates remarkable absorption in both the ultraviolet and visible light regions [ 34 , 35 ]. In contrast, upon Ag 2 S modification on the surface of mTiO 2 , there is a clear absorption in the visible light region.…”

Challenges and Advances in Biomarker Detection for Rapid and Accurate Sepsis Diagnosis: An Electrochemical Approach

“…Quantum dot-modified electrodes exhibit a change in photocurrent response, which successfully translates to analyte quantification. For example, the photocurrent generated by Ag 2 S quantum dot-modified Bi 2 S 3 /ITO electrodes allows the detection of picogram levels of PCT [ 80 ]. (iv) Electrochemically active redox couple molecules serve as promising biomarker labels.…”

“…This sandwich-type Ab1/PCT/An2-non-noble OER catalyst architecture ( Figure 8 ) achieved the LOD of 0.33 pg mL −1 . The photoelectrochemical method was also applied for the design of a PCT sensor, with the use of a Bi 2 S 3 /Ag 2 S catalyst for the production of photocurrent [ 80 ]. Owing to the specific attraction between the antigen and a modified electrode, photocurrent intensity was found to decrease owing to the electron transfer hindrance effect.…”

Advances in nanoprobes‐based immunoassays

“…As expected, a signal-enhanced immunosensor can be achieved by amplifying the photocurrent signal through the formation of a sandwich immunostructure, and the photocurrent was linear with the common logarithm of CYFRA21-1 ranging from 100 fg mL −1 to 50 ng mL −1 , with a LOD of 56 fg mL −1 . Zhao et al [63] established a PECI method based on the energy level matching principle of Bi 2 S 3 and Ag 2 S to realize the sensitive detection of procalcitonin (Figure 8d). This admirable platform shows a good linear range of 0.5 pg mL −1 -50 ng mL −1 and a low detection limit of 0.18 pg mL −1 .…”

“…[60] Copyright 2019, American Chemical Society. The sensitivity of the PECI sensor was improved by copper in situ deposition signal amplification (b) [61] , heterojunction modification (c) [62] , and energy level matching principles (d) [63] . Copyright 2019, Royal Society of Chemistry.…”