CRP human ELISA kit
CE certified for IVD use | Precoated plates | Ready to use reagents
96 well precoated ELISA microplate
Incubation time: 1 h 10 min
Range: 5 - 100 µg/ml
Sensitivity: 1 µg/ml
Sample size: 100 µl (1/1000 predilution)
Sample type: serum or plasma
Substrate: TMB 450nm
1. INTENDED USE
Immunoenzymetric assay for the in vitro quantitative measurement of human C-reactive protein (CRP) in serum and plasma.
2. CLINICAL BACKGROUND
C-Reactive Protein (CRP) is an acute-phase protein, produced exclusively in the liver. Interleukin-6 is the mediator for the synthesis by the hepatocytes of CRP, a pentamer of approximately 120,000 Daltons. CRP is present in the serum of normal persons at concentrations ranging up to 5 mg/l. The protein is produced by the foetus and the neonate and it does not pass the placental barrier, as such it can be used for the early detection of neonatal sepsis. Because febrile phenoena, leukocyte count and erythrocyte sedimentation rate (ESR) are often misleading, investigators and clinicians now prefer a quantitative CRP determination as a marker for acute inflammation and tissue necrosis. Within 6 hours of an acute inflammatory challenge the CRP level starts to rise. Serum concentration of CRP increases significantly in cases of both infectious and non-infectious inflammation, of tissue damage and necrosis and in the presence of malignant tumours. CRP is present in the active stages of inflammatory disorders like rheumatoid arthritis, ankylosing spondylitis, Reiter's syndrome, psoriatic arthropathy, systemic lupus erythematosus, polyarthritis, ulcerative colitis and Crohn's disease. Injuries causing tissue breakdown and necrosis are associated with increases in serum CRP which are seen in thermal burns, major surgery and myocardial infarction. Widespread malignant disease with carcinoma of the lung, stomach, colon, breast, prostate and pancreas, Hodgkin's disease, non-Hodgkin's lymphoma and lymph sarcoma will give rise to high levels of CRP resulting from tissue damage by invading tumour cells. CRP therefore may be used to monitor malignancy. The CRP level increases dramatically following microbial infections, and this may be particularly helpful for the diagnosis and monitoring of bacterial septicaemia in neonates and other immunocompromised patients at risk. In children, CRP is useful for differential diagnosis of bacterial and viral meningitis. Because the biological half-life of this protein is only 24 hours, CRP accurately parallels the activity of the inflammation process and the CRP concentration decreases much faster than ESR or any other acute phase parameter, which is particularly useful in monitoring appropriate treatment of bacterial diseases with antibiotics. C-Reactive Protein measurements during the early and late post-transplant period of bone marrow and organ transplantations is particularly useful in the management of interfering infections in these immunosuppressed patients.
3. PRINCIPLES OF THE METHOD
Microtiterstrips pre-coated with anti-CRP antibody are incubated with diluted standard sera and patient samples. During this incubation step, CRP is bound specifically to the wells. After removal of the unbound serum proteins by a washing procedure, the antigen-antibody complex in each well is detected with specific peroxidase-conjugated antibodies. After removal of the unbound conjugate, the strips are incubated with a chromogen solution containing tetramethylbenzidine and hydrogen peroxide: a blue colour develops in proportion to the amount of immunocomplex bound to the wells of the strips. The enzymatic reaction is stopped by the addition of 0.5M H2SO4 and the absorbance values at 450 nm are determined. A standard curve is obtained by plotting the absorbance values versus the corresponding standard values. The concentration of CRP in patient samples is determined by interpolation from the standard curve.