Serum samples are diluted and added into the microtiter plate wells coated with Lactobacillusplantarum which metabolizes niacin.The presence of niacin both in standards [STD] and samples gives a niacin-dependent growth response. After incubation at 37°C for 48 hours, the growth of Lactobacillus plantarum is measured turbidimetrically at 610 - 630 nm (alternative at 540 - 550nm) in an ELISA-reader.Adose response curve of absorbance unit (optical density, ODat 610nm) vs.concentration is generated using the values obtained from standard. Niacin present in the patient samples is determined directly from this curve. Sample Types: serum. Range: 2 - 40 μg/L. Sensitivity: 2 μg/L. Time: 48 hours ? The Eagle Biosciences Niacin is a microtiter plate test kit based on a microbiological assay which measures the total niacin content (nicotinic acid and nicotinamide) in serum.The test kit contains all required reagents,e.g.standard,medium and microtiter plate coated with a specific microorganism, sufficient for 96 determinations including standard curves.An ELISA reader is required for evaluation of the niacin content. The Niacin Assay kit is For Research Use Only.