Development and validation of a fast quantitative method for plasma dimethylarginines analysis using liquid chromatography-tandem mass spectrometry.

Objectives: The aim of this work was to implement a fast, accurate and simple method to quantify plasma ADMA and SDMA, in a run time suitable for routine analysis. Design and methods: We developed and validated a hydrophilic interaction chromatographic method coupled to tandem mass spectrometry (HILIC-MS/MS) for separation and Simultaneous quantification of Arginine (Arg) and its dimethylarginines, ADMA and SDMA, with a short run time (less than 5 min) using a small volume of human plasma (0.02 mL). Results: Correlation coefficients (r) of the calibration curves ranged from 0.9926 to 0.9984. Within-day and between-day imprecision (CV%) and inaccuracy (%), carry-over and recovery were also evaluated for validation. Preliminary data of Arg, ADMA and SDMA from 30 apparently healthy subjects and type 2 diabetic patients (n=33) with and without kidney dysfunction were calculated and some statistical differences occurred among them (p<0.05). Conclusions: Data from calibration curves and quality controls reveal that the method is accurate and precise. Healthy subjects and diabetic patients' values are in agreement with those reported in other studies. (C) 2008 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.