- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
LED visible-light driven label-free photoelectrochemical immunosensor based on WO3/Au/CdS photocatalyst for the sensitive detection of carcinoembryonic antigen
摘要： A ternary WO3/Au/CdS photocatalyst was prepared by reversible redox and ionic adsorption for the first time. The photocatalyst exhibited high photocatalytic activity and good photoelectrochemical (PEC) property in comparison with WO3, CdS, WO3/Au and WO3/CdS, because the localized surface plasmon resonance (LSPR) effect of Au nanoparticles (Au NPs) and the sensitization of CdS benefited the spatial separation of photogenerated electron-hole pairs and the absorption of visible light. Thus, its photocurrent response intensity was quite high, up to about 218-fold of WO3 and 87-fold of CdS under 430 nm LED light irradiation. Based on the large anodic photocurrent and the specific recognition between carcinoembryonic antigen (CEA) and anti-CEA, a novel PEC immunosensor was constructed for the sensitive and selective detection of CEA. Under the selected conditions, the change of photocurrent intensity was linear to the logarithm of CEA concentration over the range from 0.01 to 10 ng/mL, and the detection limit was down to 1 pg/mL. The immunosensor also showed good stability, reproducibility and repeatability. It was successfully applied to the detection of CEA in serum samples.
关键词： Au nanoparticles,WO3,Photoelectrochemical immunosensor,Carcinoembryonic antigen,CdS
更新于2025-11-21 11:01:37
-
Facile synthesis of two-dimensional tailored graphitic carbon nitride with enhanced photoelectrochemical properties through a three-step polycondensation method for photocatalysis and photoelectrochemical immunosensor
摘要： Graphitic carbon nitride (g-C3N4) is an ideal alternative two-dimensional (2D) nanostructure for photocatalysis and photoelectrochemical (PEC) application, while controllably fabricating 2D shaped g-C3N4 nanolayers/nanosheets is still facing challenges. On the basis of temperature-dependent polymorphic characters, herein, a 2D extending g-C3N4 (g-CNS3) is synthesized from dicyandiamide as the precursor by operating the condensation temperature in a continuously three-step thermal polycondensation procedure. The g-CNS3 with film-like morphology showed improved visible-light absorption ability and enhanced PEC performance compared to g-CNS1 synthesized via the traditional one-step thermal polymerization method. Benefiting from its excellent PEC properties, the g-CNS3 exhibited high photocatalytic activity to removal MB with fast kinetics and served as the photoactive layer to construct a PEC immunosensor with high sensitivity and specificity for subgroup J avian leukosis virus detection. A linear range from 102.14 to 103.35 TCID50/mL and a detection limit of 102.08 TCID50/mL were obtained for the PEC immunoassay of the target virus. This work might provide a novel protocol for tailoring shaped 2D g-C3N4 nanosemiconductor with superior properties and shed light on its promising PEC applications.
关键词： Two-dimensional material,Photocurrent response,Graphitic carbon nitride,Photocatalysis,Photoelectrochemical immunosensor
更新于2025-09-23 15:23:52
-
Polydopamine nanospheres loaded with l-cysteine-coated cadmium sulfide quantum dots as photoelectrochemical signal amplifier for PSA detection
摘要： A sandwich-type photoelectrochemical (PEC) immunosensor was constructed for sensitive detection of prostate specific antigen (PSA). It was based on electrochemically reduced graphene oxide-TiO2 (ERGO-TiO2) as photoelectrochemical platform to immobilize capture antibody (Ab1). Then, quinone-rich polydopamine nanospheres (PDANS) loaded detection antibody (Ab2) and photocurrent signal label, L-cysteine-coated cadmium sulfide quantum dots (CdSQDs). ERGO-TiO2 displayed greatly improved photocurrent response to white light. CdSQDs conjugated with PDANS further amplified photocurrent signal because of the good conductivity of PDANS and ERGO. The increased photocurrent showed a linear correlation with PSA in the concentration range from 0.02 pg mL?1 to 200 ng mL?1 with the detection limit of 6.8 fg mL?1. It also revealed high selectivity and good stability.
关键词： Electrochemically reduced graphene oxide-TiO2,Polydopamine nanospheres,Photoelectrochemical immunosensor,L-cysteine-coated cadmium sulfide quantum dots,Prostate specific antigen
更新于2025-09-12 10:27:22
-
Simultaneous Unlocking Optoelectronic and Interfacial Properties of C <sub/>60</sub> for Ultrasensitive Immunosensing by Coupling to Metal?Organic Framework
摘要： Due to exceptional electron-accepting ability, light-absorption and delocalized conjugated structure, buckminsterfullerene (C60) has attracted fascinating interests in the field of organic solar cells. However, poor delocalization and accumulation of electrons for pristine C60 in physiological aqueous solution and difficulties in conjugation with biomolecules limit its extended photovoltaic applications in bioassay. Herein, we reported the non-covalent coupling of C60 to an electronically complementary porphyrin-derived metal-organic framework (PCN-224) with carboxyl-group terminals. Such assembly not only offered a friendly interface for bioconjugation but also resulted in a long-range ordering C60@PCN-224 donor-acceptor system that demonstrated an unprecedented photocurrent enhancement up to 10 times with respect to each component. As an example, by further cooperating with Nanobodies, the as-prepared C60@PCN-224 was applied to a photoelectrochemical (PEC) immunosensor for S100 calcium-binding protein B with by far the most promising detection activities. This work may open a new venue to unlock the great potential of C60 in PEC biosensing with excellent performances.
关键词： photoelectrochemical immunosensor,S100 calcium-binding protein B,Nanobodies,metal-organic framework,C60
更新于2025-09-11 14:15:04
-
Sandwich-type signal-off photoelectrochemical immunosensor based on dual suppression effect of PbS quantum dots/Co3O4 polyhedron as signal amplification for procalcitonin detection
摘要： A novel signal-off photoelectrochemical (PEC) immunosensor was proposed for procalcitonin (PCT) sensitive detection based on the Au nanoparticles/BiOI nanosheets/Black TiO2 nanoparticles (Au NPs/BiOI NSs/B-TiO2 NPs) as photoactive matrix and PbS quantum dots/Co3O4 polyhedron (PbS/Co3O4) as a quenching signal label for signal amplification. Concretely, BiOI NSs was fabricated by successive ionic layer absorption and reaction (SILAR) and formed the interlaced flake-like structure. Then Au NPs dropped on the BiOI NSs/B-TiO2 NPs electrode forming Au NPs/BiOI NSs/B-TiO2 NPs sensitization structure, which increased the utilization of visible light and accelerated electron transfer rate, resulting in a desirable PEC signal. PbS/Co3O4, an effective dual suppression signal quencher, was proposed for signal-off PEC immunosensor to weaken the photocurrent response because of the steric impedance, competitive absorption of light and competing consumption of electron donor. In this proposal, PCT was chosen to measure the performance of the suggested PEC immunosensor. Consequently, the fabricated PEC immunosensor showed a widely detection ranged from 0.1 pg/mL to 50 ng/mL and a low detection limit of 0.02 pg/mL (S/N = 3). What is more, the proposed PEC immunosensor possessed satisfactory selectivity, stability and reproducibility.
关键词： Dual suppression effect,Procalcitonin,Photoelectrochemical immunosensor,Signal-off
更新于2025-09-11 14:15:04