Calbiotech Vitamin D 25(OH) Elisa Kit

Product Description

SUMMARY AND EXPLANATION
Vitamin D is a steroid hormone involved in the active intestinal absorption of calcium and in the regulation of itshomeostasis. Vitamin D has two isomers: Vitamin D2 and Vitamin D3. Vitamin D2 is obtained from dairy productswhereas Vitamin D3 is produced in the skin after exposure to ultraviolet light. In the liver, Vitamin D ishydroxylated at its carbon 25 to form 25-OH Vitamin D. This metabolite is the predominant circulating form ofVitamin D and is considered to be an accurate indicator of the general Vitamin D status of an individual. Vitamin Ddeficiency has been linked to many diseases including osteoporosis, rickets, osteomalacia, cancers, andcardiovascular diseases. Both dietary supplements of Vitamin D that are currently available in the market (VitaminD2 and Vitamin D3) are converted to 25-OH Vitamin D in the liver. The sum of the concentrations of 25-OHVitamin D2 and 25-OH Vitamin D3, in serum or plasma, is referred to as "Total 25-OH Vitamin D. Accuratemonitoring of total 25-OH Vitamin D level is critical in clinical settings. Vitamin D deficient patients who areprescribed a daily Vitamin D supplement should regularly monitor their serum or plasma Vitamin D levels in orderto reach an optimal level and prevent their 25-OH Vitamin D concentrations from reaching excessive levels thatare considered toxic

PRINCIPLE OF THE TEST
The kit is a solid phase enzyme-linked immunoassay (ELISA), based on the principal of competitive binding. AntiVitamin D antibody coated wells are incubated with Vitamin D standards, controls, samples, and Vitamin D-Biotinconjugate at room temperature for 90 minutes. During the incubation, a fixed amount of biotin-labeled vitamin Dcompetes with the endogenous Vitamin D in the sample, standard, or quality control serum for a fixed number ofbinding sites on the anti Vitamin D antibody. Following a wash step, bound Vitamin D-Biotin is detected withStreptavidin-HRP (SA-HRP). SA-HRP conjugate immunologically bound to the well progressively decreases asthe concentration of Vitamin D in the specimen increases. Unbound SA-HRP conjugate is then removed and thewells are washed. Next, a solution of TMB Reagent is added and incubated at room temperature for 30 minutes,resulting in the development of blue color. The color development is stopped with the addition of stop solution, andthe absorbance is measured spectrophotometrically at 450 nm. A standard curve is obtained by plotting theconcentration of the standard versus the absorbance. The color intensity will be inversely proportional to theamount of 25-OH Vitamin D in the sample. The assay measures both the 25-OH Vitamin D2 and D3. The totalassay procedure run time is 2.5 hours.