The use of NADH as a standard in a modified PMS-INT colorimetric assay of lactate dehydrogenase.
A new and more reliable way of quantitating lactate dehydrogenase activity, using NADH as a standard in a colorimetric assay, is proposed. Adopting the scheme, we obtained a CV of 2.6% and precision (95% limits) of +/-5.4% for enzyme activities ranging from 110 to 600 U/l. Comparative study against the modified kinetic method of Amador et al. showed excellent correlation, r = 0.99, p  less than 0.001. A normal range of 75 to 203 U/l was determined for the proposed scheme.
D003124:Colorimetry / Q000379:methods; D005069:Evaluation Studies as Topic; D006801:Humans; D007202:Indicators and Reagents; D007770:L-Lactate Dehydrogenase / Q000097:blood*; D008773:Methylphenazonium Methosulfate; D009243:NAD; D013778:Tetrazolium Salts
D007202:Indicators and Reagents; D013778:Tetrazolium Salts; D009243:NAD; D008773:Methylphenazonium Methosulfate; D007770:L-Lactate Dehydrogenase