Quantification of plasma S-adenosylmethionine and S-adenosylhomocysteine as their fluorescent 1,N6-etheno derivatives:: an adaptation of previously described methodology

A simplified reversed phase HPLC system for the detection of fluorescent 1,N-6-etheno derivatives of SAM (S-adenosylmethionine) and S-adenosylhomocysteine (SAH) is described. The most important changes from the previously reported method are a shorter derivatization reaction time, the use of a solid-phase extraction resulting in an increase of the method's sensitivity, and the use of only one chromatographic system to separate SAM and SAH (in which the use of an ion-pairing reagent in the mobile phase is avoided). The linearity of the method was established, and the intra-assay coefficients of variation were 10.4 and 4.7% for SAM and SAH, respectively. Normal plasma values (n = 8), evaluated with the present methodology, were, for SAM and SAH, respectively, 57 +/- 12 and 28 +/- 3 nM (mean +/- SD). (C) 2002 Elsevier Science B.V. All rights reserved.