CoproELISA C difficile GDH Assay Kit
The CoproELISA C difficile GDH Assay is For Research Use Only
Size: 1×96 wells
Sensitivity: Cut-Off Control
Incubation Time: < 2 hours
Sample Type: Stool
Sample Size: 0.1 to 0.3g
Alternative Name: Clostridium difficile glutamate dehydrogenase
The gram-positive anaerobic bacillus Clostridium difficile is the leading causative agent of antibiotic-associated diarrhea and pseudomembranous colitiss. This pathogen is capable of causing disease that could be severe or fatal if not diagnosed on time and treated. Exposure to antibiotics is the major risk factor for C. difficile infection. Infection can develop if the normal gastrointestinal flora is disrupted by antibiotic therapy and a person acquires toxin-producing C. difficile, typically via the fecal-oral route. C. difficile’s key virulence factors are toxin A and toxin B. These toxins show high sequence and functional homology. Toxin A has been described as a tissue damaging enterotoxin which attracts neutrophils and monocytes and toxin B as a potent cytotoxin that degrades the colonic epithelial cells. Most virulent strains produce both toxins, however, toxin A negative/toxin B positive strains are also capable of causing disease. All strains of C. difficile produce high levels of GDH. Therefore, C. difficile’s GDH enzyme is considered a very good antigen marker for detection of this organism. The CoproELISA C. difficile GDH test is a highly specific and sensitive diagnostic kit for GDH in stool specimens. A positive result confirms the presence of C. difficile and a negative result indicates its absence. A separate test should be performed to confirm the presence of C. difficile toxins in the GDH positive samples.
CoproELISA C. difficile Toxin A B Assay Kit
CoproELISA H Pylori Assay Kit
Break-apart microwells are coated with C. difficile GDH specific monoclonal antibodies. A horseradish peroxidase (HRP) conjugated monoclonal anti-GDH antibody is added to the antibody-coated microwells. Fecal samples are diluted in sample diluent and added to the microwells. In this step C. difficile GDH is marked by the HRP conjugated antibody and immobilized by the coated antibody. Unbound conjugate is removed by washing. TMB-substrate is added, the substrate is hydrolyzed by the peroxidase and yields a blue solution of the reduced substrate. Upon the addition of the stop solution, the blue color turns yellow and should be read by an ELISA reader at a wavelength of 450/620 nm. The absorbance is proportional to the level of C. difficile GDH in the sample.
The CoproELISA C. difficile GDH test was evaluated using microbial culture isolates and clinical stool specimens*. No cross-reactivity was observed with any of the gastrointestinal pathogens and microbes listed: Blastocystis, Campylobacter, Cryptosporidium parvum, Dientamoeba fragilis, Escherichia coli, Entamoeba histolitica, Enterococcus faecali, Enterococcus faesium, Enterococcus avium, Enterococcus aerogenes, Enterococcus cloacae, Enterococcus gallinarum, Enterococcus durans, Giardia lamblia, Helicobacter pylori, Klebsiella pneumonia,
Salmonella enterica, and Shigella.
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