CLIA Reagents of Inflammation (HCY)

【Expected usage】
For in vitro quantitative detection of homocysteine ​​(HCY) in human serum.

Homocysteine ​​(HCY) is a sulfur-containing amino acid in the human body. It is an important intermediate product in the metabolic process of methionine and cysteine, and is not involved in protein synthesis itself. Homocysteine, also known as homocysteine ​​(Homocysteine, HCY), is an intermediate metabolite of methionine.

It can generate cysteine ​​under the catalysis of cystathionine condensing enzyme (CBS) and cystathionase, which requires the participation of vitamin B6, or can be combined with sulfhydryl to generate homocysteine. In addition, HCY can also be in folic acid and vitamin B12. Re-methylation to synthesize methionine under the auxiliary action of methionine, this process requires the catalysis of methionine synthase (MS), and must have N5-methyltetrahydrofolate as a methyl donor, the latter is Tetrahydrofolate is catalyzed by 5,10-methyltetrahydrofolate reductase (MTHFR). HCY has been widely accepted as an independent cardiovascular risk indicator and is another risk factor besides hyperlipidemia, smoking and diabetes.

At present, the determination methods of homocysteine ​​in clinical and laboratory include enzyme-linked immunosorbent assay, colloidal gold method, fluorescence immunoassay, and chemiluminescence method.

【Inspection Principle】
This kit adopts the principle of competition method, uses magnetic microparticles as the solid phase of immune reaction, and uses chemiluminescence enzyme-linked immunosorbent assay method to cooperate with chemiluminescence measuring instruments to detect the content of HCY in human serum.

The technical principle is: the bound or dimerized HCY (oxidized form) is reduced to free HCY under the action of dithiothreitol (DTT). In the presence of sufficient amounts of adenosine, free HCY is converted to S-adenosyl-homocysteine ​​(SAH) by recombinant S-adenosyl-homocysteine ​​hydrolase (rSAHHase).

SAH competes with magnetic particle-bound labeled SAH for binding to alkaline phosphatase (AP)-labeled mouse monoclonal anti-SAH antibody. Direct precipitation in an applied magnetic field separates the immunoreactive complexes from unbound other substances. The precipitated complex is washed, and an enzymatic chemiluminescent substrate (adamantane derivative) is added, and the substrate is catalytically cleaved under the action of the enzyme to form an unstable excited state intermediate, which emits light when the excited state intermediate returns to the ground state.

The photons form a luminescence reaction, and the luminescence intensity of the reaction is measured by a luminometer. In the range of measurement wavelength (230-700nm), the luminescence intensity is inversely proportional to the concentration of HCY in the sample, and the HCY concentration in the sample to be tested can be quantitatively measured by fitting the improved four-parameter Logistic equation.