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Complement factor I ELISA Kit [Human], 1 x 96 det. (CAT#: CB-P135-K) Datasheet

Product Type
CFI is a protein of the complement system (serine protease), also known as C3b/C4f inactivator, and is a protein encoded by the CFI gene located on chromosome 4. It regulates complement activation by cutting cell binding or liquid phases C3b and C3b. C4b. CFI is mainly synthesized in the liver and is initially secreted as a single 88 kDa gene product. Then, the precursor protein is cleaved by furin to produce a mature CFI protein, which is the disulfide of heavy chain residues (residues 19-335, 51 kDa) and light chain (residues 340-583, 37 kDa) Bonded dimers. Only mature proteins are active. Genetic polymorphisms in CFI have been observed (variants R201S, R406H, R502L). Because the activation of the alternative pathway of complement is not controlled, CFI deficiency can lead to a decrease in the level of complement component 3 (C3) in the plasma, and is associated with repeated bacterial infections in children. Recently, it has been proved that mutations in the CFI gene are related to the development of hemolytic uremic syndrome, which is also a kidney disease caused by unregulated complement activation.
Complement factor I ELISA kit is used for the in vitro quantitative determination of human CFI in plasma and serum.
Complement factor I ELISA kit is a ready-to-use solid-phase enzyme-linked immunosorbent assay based on the sandwich principle. The working time is 3 hours. The effective form of the plate with twelve disposable 8-well plates allows free choice of batch size for determination. The samples and standards are incubated in microtiter wells coated with antibodies that recognize human CFI. The biotinylated tracer antibody will bind to the captured human CFI. The streptavidin-peroxidase conjugate will bind the biotinylated tracer antibody. The streptavidin-peroxidase conjugate will react with the substrate tetramethylbenzidine (TMB). The enzyme reaction is stopped by adding oxalic acid. Measure the absorbance at 450nm with a spectrophotometer. Draw a standard curve by plotting the absorbance (linear) relative to the corresponding concentration (logarithm) of the human CFI standard. The human CFI concentration of samples run at the same time as the standard can be determined from the standard curve.
1 x 96 det.
Detection Method
Enzyme immunoassay (ELISA) technique
Detection Limit
Measurable concentration range of 35.1 to 400 ng/ml.
Minimum concentration which can be measured is 35.1 ng/ml.
Serum, plasma, tissue homogenates, cell lysates, cell culture supernates and other biological fluids
Specimen Collection
Blood samples were collected using sterile venipuncture techniques, and serum was obtained using standard procedures. At least 5 ml of whole blood is recommended. Let the blood clot in the serum test tube for 60-65 minutes at room temperature (20-25°C). Centrifuge the blood sample and transfer the cell-free serum to a clean test tube. The serum must be handled correctly to prevent complement activation in vitro. Serum should be frozen in a sealed tube at -70°C or lower for long-term storage or transport on dry ice. The sample should not be frozen and thawed more than once. Do not use jaundice, lipemia and hemolytic serum. You cannot use heat-inactivated serum. Plasma cannot be used.
Sample Volume
100 µl/well
Species Reactivity
Cross Reactivity
Mouse - No, Pig - No, Rat - No
Protocol Length
2 hours
Product should be stored at 4 °C. Under recommended storage conditions, product is stable for at least six months.
Research Use
For research use only. Not for use in or on humans or animals or for diagnostics. It is the responsibility of the user to comply with all local/state and Federal rules in the use of this product. Hycult Biotech is not responsible for any patent infringements that might result with the use of or derivation of this product.

All products and services are for Research Use Only. Do Not use in humans.


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