Determination of lysophosphatidic acids by capillary electrophoresis with indirect ultraviolet detection.

Lysophosphatidic acid (LPA) is the simplest form of lysophospholipid. Molecular species of LPA have been identified as the potent components in the ovarian cancer activation factor. The elevated plasma LPAs may be used as potential biomarkers for the early detection of ovarian cancer. This paper is the first report on the quantitative analysis of molecular species of LPA using capillary electrophoresis. In this work, the separation of LPAs was achieved within 14 min in an adenosine monophosphate-borate-methanol-water solution, and the measurement was accomplished by indirect UV detection. With LPA (D) as internal standard, the method had linear calibration ranges for LPAs from 2.8 to 75 microM. The detection limits for various molecular species of LPA were from 1.2 to 2.3 microM by the pressure injection at 3.45 kPa for 5 s. The method had been applied to serum fortified with LPA (S), LPA (O), LPA (P), and LPA (M) and the recoveries ranged from 83 to 112%.