Quantitative assay for 25-hydroxyvitamin D
The Total 25OH Vitamin D ELISA (BIOHIT) is a precise quantitative assay designed to measure 25-hydroxyvitamins D2 and D3 in serum and plasma, playing a crucial role in diagnosing vitamin D deficiency, insufficiency, or intoxication. This test is vital because the accurate diagnosis of vitamin D status depends on the measurement of both 25OHD2 and 25OHD3, which are essential for understanding how well the body absorbs calcium.
The 25OH vitamin D test is a microplate-based competitive enzyme-linked immunosorbent assay (ELISA). This assay involves adding samples, controls, and calibrators to microtiter plate wells with incubation buffer, which facilitates the binding of 25OH vitamin D to specific antibodies. Following several precise steps, including the introduction of biotin-labelled and streptavidin-labelled compounds, washing, and the addition of a chromogenic substrate (TMB), the test measures the 25OH vitamin D concentration by interpreting the colour intensity, which is inversely proportional to the concentration. This process ensures reliable results through calibration curve interpolation.