For in vitro diagnostic use. The RIDASCREEN® Biotin test is an enzyme binding assay in microtiter format for the quantitative determination of Biotin (vitamin H) in serum or plasma .
Biotin, also known as vitamin H, is of great importance for the biochemistry of the human organism. It influences the growth and maintenance of blood cells, sebaceous glands, skin, hair and nails. Next to the free form of biotin, the biotin linked lysin can also be utilized as a vitamin source by the body, after cleavage from the protein by enzyme reaction. In nature, biotin is very common but the bioavailability varies very strongly and depends on the food and on the extend to which biotin is protein-bound. The treatment of food also causes losses in biotin. As a result a biotin defiancy can easily occur which may lead to a variety of disorders on hair, skin and nails. Independent from the cause, a biotin deficiency always exists when the plasma biotin level is below 100 ng/ml. In this case, a substitution should definitely occur.
The common microbiological procedures and isotope dilution tests are very time consuming and not suitable for a big number of samples. In contrast, the quantitative detection of biotin with the RIDASCREEN® Biotin kit is much easier and faster to carry out .
The basis of the test is the extremely high affinity of avidin, a protein produced by microorganisms, to biotin. The microtiter plates are coated with avidin. Samples, biotin standards and enzyme-labelled biotin (conjugate) are added. Free and enzyme-labelled biotin compete for the avidin-binding sites. Any unbound enzyme-labelled biotin is then removed by a washing step. The detection occurs with the addition of substrate (urea peroxide) and chromogen (tetramethylbenzidine). The conjugate, that is bound to avidin, changes the colorless chromogen to a blue end product. The addition of the stop solution causes a color change from blue to yellow. The measurement is done photometrically at 450 nm (optional: reference wavelength ≥ 620 nm). The resulting absorbance values are inversely proportional to the biotin concentration of the sample.
|Test format||Microtiter plate with 96 wells (12 strips with 8 wells each)|
|Standard range||0 ng/l, 37 ng/l, 111 ng/l, 333 ng/l, 1000 ng/l Biotin|
|Incubation time||3 x 30 min at room temperature|