Sensitive Electrochemical Immunosensor For Detection Research Articles

Sensitive Electrochemical Immunosensor for Detection of Mycotoxins Aflatoxin B1 Using Disposable screen-Printed Carbon Electrode

Sensitive Electrochemical Immunosensor for Detection of Mycotoxins Aflatoxin B1 Using Disposable screen-Printed Carbon Electrode

Sensitive Electrochemical Immunosensor for Detection of Nuclear Matrix Protein-22 based on NH2-SAPO-34 Supported Pd/Co Nanoparticles.

A novel sandwich-type electrochemical immunosensor using the new amino group functionalized silicoaluminophosphates molecular sieves (NH2-SAPO-34) supported Pd/Co nanoparticles (NH2-SAPO-34-Pd/Co NPs) as labels for the detection of bladder cancer biomarker nuclear matrix protein-22 (NMP-22) was developed in this work. The reduced graphene oxide-NH (rGO-NH) with good conductivity and large surface area was used to immobilize primary antibody (Ab1). Due to the excellent catalytic activity toward hydrogen peroxide, NH2-SAPO-34-Pd/Co NPs were used as labels and immobilized secondary antibody (Ab2) through adsorption capacity of Pd/Co NPs to protein. The immunosensor displayed a wide linear range (0.001–20 ng/mL) and low detection limit (0.33 pg/mL). Good reproducibility and stability have showed satisfying results in the analysis of clinical urine samples. This novel and ultrasensitive immunosensor may have the potential application in the detection of different tumor markers.

Electrochemical immunosensor for detecting typical bladder cancer biomarker based on reduced graphene oxide–tetraethylene pentamine and trimetallic AuPdPt nanoparticles

A highly sensitive electrochemical immunosensor for detection of typical bladder cancer biomarker-nuclear matrix protein 22 (NMP22) was developed by using reduced graphene oxide–tetraethylene pentamine (rGO–TEPA) and trimetallic AuPdPt nanoparticles (NPs). rGO–TEPA was used as the ideal material for signal amplification and AuPdPt NPs immobilization due to its excellent conductivity and large surface area. An effective platform was constructed for antibodies anchoring by using AuPdPt NPs, which kept the antibodies’ high stability and bioactivity. Moreover, AuPdPt NPs could accelerate the electron transfer and enhance the signal response, which assisted by the synergistic effect of the three different metals (Au, Pd and Pt). The proposed immunosensor showed satisfied performance such as simple fabrication, low detection limits (0.01U/mL), wide linear range (from 0.040 to 20U/mL), short analysis time (2min), high stability and selectivity in the detection of NMP22. Furthermore, the proposed immunosensor was employed to test real urine samples with satisfactory results.

Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon nanotube–graphene composite and functionalized mesoporous materials

A facile and sensitive electrochemical immunosensor for detection of human chorionic gonadotrophin (hCG) was designed by using functionalized mesoporous nanoparticles as bionanolabels. To construct high-performance electrochemical immunosensor, Au nanoparticles (AuNPs) dotted carbon nanotubes (MWCNTs)–graphene composite was immobilized on the working electrode, which can increase the surface area to capture a large amount of primary antibodies (Ab1) as well as improve the electronic transmission rate. The as-prepared bionanolabels. composed of mesoporous silica nanoparticles (MCM-41) coated with AuNPs through thionine linking, showed good adsorption of horseradish peroxidase-labeled secondary anti-hCG antibody. Interlayer thionine was not only a bridging agent between MCM-41 and AuNPs but also an excellent electron mediator. The approach provided a good linear response range from 0.005 to 500mIUmL−1 with a low detection limit of 0.0026mIUmL−1. The immunosensor showed good precision, acceptable stability and reproducibility. Satisfactory results were obtained for determination of hCG in human serum samples. The proposed method provides a new promising platform of clinical immunoassay for other biomolecules.