Micellar electrokinetic capillary chromatography (MECC) was applied to develop an analytical method for quantitation of ribonucleoside triphosphates (rNTPs) in human lymphoid cells obtained from patients with B-chronic lymphocytic leukaemia (B-CLL) and cutaneous lymphomas. The results of this analysis showed a significant depression of intracellular rNTPs in patients with B-CLL, compared with rNTPs of healthy controls. These data are in agreement with other studies in which rNTP separations were performed with traditional high-performance liquid chromatography. MECC has proved to be a useful tool for intracellular rNTPs determination, revealing possible new applications in the study of the metabolic state of human cells. In addition, this m...