Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30536 (PBS)
 9,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A fluorescence sandwich immunoassay using high-affinity antibodies and quantum dot (QD) reporters has been developed for detection of botulinum neurotoxin serotype A (BoNT/A) using a nontoxic recombinant fragment of the holotoxin (BoNT/A-H(C)-fragment) as a structurally valid simulant for the full toxin molecule. The antibodies used, AR4 and RAZ1, bind to nonoverlapping epitopes present on both the full toxin and on the recombinant fragment. In one format, the immunoassay is carried out in a 96-well plate with detection in a standard plate reader using AR4 as the capture antibody and QD-coupled RAZ1 as the reporter. Detection to 31 pM with a total incubation time of 3 h was demonstrated. In a second format, the AR4 capture antibody was coupled to Sepharose beads, and the reactions were carried out in microcentrifuge tubes with an incubation time of 1 h. The beads were subsequently captured and concentrated in a rotating rod "renewable surface" flow cell equipped with a fiber optic system for fluorescence measurements. In PBS buffer, the BoNT/A-H(C)-fragment was detected to concentrations as low as 5 pM using the fluidic measurement approach.
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PMID:Quantum dot immunoassays in renewable surface column and 96-well plate formats for the fluorescence detection of botulinum neurotoxin using high-affinity antibodies. 1964 93

In this work, a novel nanocomposite film consisting of the Au nanoparticles/graphene-chitosan has been designed to construct an impedimetric immunosensor for a rapid and sensitive immunoassay of botulinum neurotoxin A (BoNT/A). BoNT/A antibody was immobilized on glassy carbon electrode modified with Au nanoparticles/graphene-chitosan for the signal amplification. The fabrication of immunosensor was extensively characterized by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The impedance changes, due to the specific immuno-interactions at the immunosensor surface that efficiently restricted the electron transfer of redox probe Fe(CN)64-/3- were utilized to detect BoNT/A. The measurements were highly targeted specific and linear with logarithmic BoNT/A concentrations in PBS, milk and human serum across a 0.27-268pgmL-1 range and associated with a detection limit of 0.11pgmL-1.
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PMID:Impedimetric immunosensor for the label-free and direct detection of botulinum neurotoxin serotype A using Au nanoparticles/graphene-chitosan composite. 2766 69