Anion-exchange reactions: facile and general access to sensitive photoelectrochemical platforms for biomarker immunosensing

Abstract

The combination of CdSe NCs with biocatalytic precipitation provides a highly sensitive immunosensing strategy.

Photoelectrochemical Immunoassays

“…On the basis of the HRP accelerated oxidation of 4-chloro-1-naphthol (4-CN) by H 2 O 2 to yield the insoluble and insulating product benzo-4-chlorohexadienone on the transducer surface, an isolating barrier would thus be produced against the interfacial electron transfer and thereby altered the light-absorption feature of the electrode obviously. Consequently, the holes of the excited QDs cannot interact with the donor directly due to the blocking by the precipitate, which could decrease the hole trapping capacity of QDs and result in the declined generation of photocurrent. , Following this strategy, a lot of BCP-based PEC immunoassays have been reported. , For example, Tu and co-workers reported a low potential and competitive PEC immunoassay of CEA; Zhang et al used the HRP-catalyzed BCP to amplify the PEC immunoassay of tumor-associated carbohydrate antigen . Since the product of the ALP-catalyzed BCP reaction was of indigo color, Chen and co-workers recently realized the simultaneous PEC and visualized immunoassay of β-human chorionic gonadotrophin (β-HCG) .…”

“…52,128 Following this strategy, a lot of BCP-based PEC immunoassays have been reported. 128,143 For example, Tu and co-workers reported a low potential and competitive PEC immunoassay of CEA; 91 Zhang et al used the HRP-catalyzed BCP to amplify the PEC immunoassay of tumor-associated carbohydrate antigen. 94 Since the product of the ALP-catalyzed BCP reaction was of indigo color, Chen and co-workers recently realized the simultaneous PEC and visualized immunoassay of β-human chorionic gonadotrophin (β-HCG).…”

Photoelectrochemical Cytosensors

“…PEC aptasensing [24], PEC enzymatic biosensors [26], and PEC immunoassays [28,[32][33]. However, PEC cytosensing, as an important category of PEC bioanalysis, has not been discussed systematically.…”

“…Assembling with these superiorities, PEC biosensing has become a powerful tool in the field of advanced analytical science. In the past few years, several specific topics linked to PEC bioanalysis have been exhaustively discussed, e. g. general development of PEC bioanalysis [21, 30], PEC DNA biosensors [22], PEC detection of metal ions [31], PEC aptasensing [24], PEC enzymatic biosensors [26], and PEC immunoassays [28, 32–33]. However, PEC cytosensing, as an important category of PEC bioanalysis, has not been discussed systematically.…”