Enzymatic Oxydate-Triggered Self-Illuminated Photoelectrochemical Sensing Platform for Portable Immunoassay Using Digital Multimeter

Abstract

Herein a novel split-type photoelectrochemical (PEC) immunosensing platform was designed for sensitive detection of low-abundance biomarkers (prostate-specific antigen, PSA, used in this case) by coupling a peroxyoxalate chemiluminescence (PO-CL) self-illuminated system with digital multimeter (DMM) readout. The PEC detection device consisted of a capacitor/DMM-joined electronic circuit and a PO-CL-based self-illuminated cell. Initially, reduced graphene oxide-doped BiVO4 (BiVO4-rGO) photovoltaic materials with good photoelectric properties was integrated into the capacitor/DMM-joined circuit for photocurrent generation in the presence of hydrogen peroxide (H2O2, as the hole-trapping reagent). A sandwich-type immunoreaction with target PSA was carried out in capture antibody-coated microplates by using glucose oxidase/detection antibody-conjugating gold nanoparticle (pAb2-AuNP-GOx). Accompanying the sandwiched immunocomplex, the labeled GOx could oxidize glucose to produce H2O2. The as-generated H2O2 could act as the coreaction reagent to trigger the chemiluminescence of the peroxyoxalate system and the PEC reaction of the BiVO4-rGO. Meanwhile, the self-illuminated light could induce photovoltaic material (BiVO4-rGO) to produce a voltage that was utilized to charge an external capacitor. With the switch closed, the capacitor could discharge through the DMM and provide an instantaneous current. Different from conventional PEC immunoassays, the as-generated photoelectron was stored in the capacitor and released instantaneously to amplify the photocurrent. Under the optimal conditions, the transient current increased with the increasing target PSA concentration in the dynamic working range from 10 pg mL(-1) to 80 ng mL(-1) with a detection limit (LOD) of 3 pg mL(-1). This work demonstrated for the first time that the peroxyoxalate CL system could be used as a suitable substitute of physical light source to apply in PEC immunoassay. In addition, this methodology afforded good reproducibility, precision, and high specificity, and the method accuracy matched well with the commercial PSA ELISA kit. Importantly, the developed split-type photoelectrochemical immunoassay could not only avoid the interfering of the biomolecules relative to the photovoltaic materials but also eliminate the need of an exciting light source and expensive instrumentation, thus representing a user-friendly and low-cost assay protocol for practical utilization in quantitative low-abundance proteins.

CdS:Mn quantum dot-functionalized g-C3N4 nanohybrids as signal-generation tags for photoelectrochemical immunoassay of prostate specific antigen coupling DNAzyme concatamer with enzymatic biocatalytic precipitation

“…The increased PSA concentration is commonly suspected to be connected with prostate cancer or other prostate diseases. Recently, different methods have been reported for PSA detection, e.g., (electro-)chemiluminescence immunoassay, enzyme immunoassay, fluorescence immunoassay, electrochemical immunoassay and radioimmunoassay (RIA) (Xu et al, 2017;Shi et al, 2016;Acevedo et al, 2002;Shu et al, 2016;Zhuang et al, 2015;Graves et al, 1992). Despite the high sensitivity of conventional immunoassays such as RIA and ELISA, they have some limitations, such as the short shelf life of 125 I-labeled antibody, radiation hazards, low sensitivity and expensive instruments.…”

Ag nanoclusters could efficiently quench the photoresponse of CdS quantum dots for novel energy transfer-based photoelectrochemical bioanalysis

“…Photoelectrochemical (PEC) bioanalysis has recently gained substantial momentum for its potential in future bioanalysis (Zhao et al, 2014;Gill et al, 2008;Shu et al, 2016;Yan et al, 2015;Zhang et al, 2013c;Li et al, 2016;Tang et al, 2015). Analysts in this field are now infatuated with exploiting exquisite signaling mechanisms for innovative applications (Zhang et al, 2012b;Zhuang et al, 2015;Wang et al, 2015;Long et al, 2011;Wang et al, 2014a, Sun et al, 2015.…”

Silicon phthalocyanine-decorated TiO2 mesocrystal coupled with multifunctional all-carbon structure for multistep cascade signal amplifier in photoelectrochemical immunoassay

“…The newly emerged photoelectrochemical (PEC) protocol with tremendous potential could be regarded as the next-generation detection platform owing to its high sensitivity, short response time, and simple apparatus [10]. This promising analytical methodology that based on the connection between the change of photocurrent and target concentration has become a powerful passport in the fields of food security, environmental monitoring, and clinical diagnostics [11]. Typically, the method commonly consists of sandwich-type and competitive-type PEC assay formats.…”

“…These comparison experiments sufficiently demonstrated the admirable photoelectric performance of dentritic SiPcs sensitized QOTM.3.3 EIS and PEC characterization of the biosensorElectrochemical impedance spectroscopy (EIS) was an available way to characterize interface properties and construction procedures of the electrodes. The electron transfer resistance (R et ) was equal to the semicircle diameter at low frequency, which represented the charge transfer resistance of redox probe accessing the layer[11]. As depicted inFig.…”