25-OH Vitamin D (Vitamin D2 and Vitamin D3) Competitive Enzyme Linked Immunosorbent Assay ELISA kit serum or plasma 2.89-130ng/ml Dialab

25-OH Vitamin D (Vitamin D2 and Vitamin D3) Competitive ELISA manufactured by Dialab



Vitamin D is a steroid hormone involved in the intestinal absorption of calcium and the regulation of calcium homeostasis. The two major forms of Vitamin D, vitamin D3 (cholecalciferol) and Vitamin D2 (ergocalciferol), have isomeric structures, but D2 is thought to be less active than D3. Vitamin D3 levels are the result of both dietary uptake and production in the skin during sun exposure from a cholesterol precursor, 7-dehydrocholesterol. D2 is obtained from plant sources. In the liver, Vitamin D is hydroxylated to give 25-Hydroxyvitamin D (25-OH D), the major circulating metabolite of Vitamin D. Both Vitamin D and 25-OH D enter the circulation bound to Vitamin D binding protein (VDBP).

Determination of 25-OH D in serum or plasma can assist diagnosis and therapeutic control of postmenopausal osteoporosis, rickets in children, osteomalacia, renal osteodystrophy, neonatal hypocalcemia and hyperparathyroidism.

The Dialab 25-OH Vitamin D ELISA for serum and plasma uses the principle of competitive binding. Samples are pre-treated with denaturing buffer to extract the vitamin D from the VDBP complex. Once neutralised the samples are mixed with enzyme conjugate and enzyme complex. Endogenous 25-OH Vitamin D in the sample competes with the 25-OH Vitamin D3 biotin conjugate to bind to the VDBP coating the microtitre plate. Bound 25-OH Vitamin D-biotin is subsequently detected by peroxidase-labelled streptavidin. Colour intensity following addition of enzyme substrate is inversely proportional to the concentration of 25-OH Vitamin D in the sample.

Kit contents:
12x8 well microtitre plate strips pre-coated with Vitamin D binding protein;
Standards 5x1ml (0, 4, 10, 25, 60, 130 ng/ml);
Controls 2x1ml (low & high);
Denaturation buffer 1x10ml;
Neutralisation buffer 1x25ml;
Enzyme conjugate 1x7ml (Vitamin D3 conjugated to biotin);
Enzyme complex 1x 7ml (Streptavidin-Peroxidase conjugate);
Substrate solution 1x14ml (Tetramethylbenzidine (TMB));
Stop solution 1x14ml (0.5M H2SO4);
Wash solution 1x30ml (40X Concentrate);
1 adhesive foil microplate cover.

Measurement wavelength: 450nm
Incubation time: 105 min (30+60 min at 37C, 15 min at room temperature)
Calibration range: 0-130ng/ml
Sensitivity : 2.89ng/ml


Store at 2-8C. Open vial stability at 2-8C is 2 months.