LC–MS/MS for The Simultaneous Determination of Polar Endogenous Adma and Cml in Plasma and Urine from Diabetics

Asymmetric dimethylarginine (ADMA) and ε-N-carboxymethyl-L-lysine (CML) are microvascular risk factors and potential biomarkers of diabetic microvascular complication.Sample preparation was achieved using acetonitrile for protein precipitation step. ADMA, CML and IS CML-d2 were separated with gradient on a Welch Ultimate(®) XB- NH2 column. The assays were validated according to current bioanalytical guidelines with respect to specificity, linearity (20-1000 ng/ml for ADMA in human plasma, 50-2000 ng/ml in urine, 10-500 ng/ml for CML in human plasma and urine), accuracy and precision, extraction recovery, matrix effect and stability.The LC-MS/MS method was successfully applied to quantification of ADMA and CML in plasma and urine samples from healthy individuals and patients with diabetic nephropathy.