学術論文|脳梗塞検査|株式会社アミンファーマ研究所

[2017-4] Higashi, K. et al., J. Chromatogr. A 1517, 79-85 (2017)

A three column-switching high-performance liquid chromatography (HPLC) using an electrochemical detector (ECD) equipped with a diamond electrode was established to determine 3-hydroxypropylmercapturic acid (3-HPMA) in urine. An extracted urine sample was consecutively fractionated using a strong anion-exchange column (first column) and a C8 column (second column) via a switching valve before application on an Octa Decyl Silyl (ODS) column (third column), followed by ECD analysis. The% recovery of 3-HPMA standard throughout the three-column process and limit of detection (LOD) were 94 ± 1% and 0.1 pmol, respectively. A solid phase extraction step is required for the sensitive analysis of 3-HPMA in urine by column-switching HPLC-ECD despite a decreased% recovery (55%) of urine sample spiked with 100 pmol of 3-HPMA. To test the utility of our column-switching HPLC-ECD method, 3-HPMA levels of 27 urine samples were determined, and the correlation between HPLC-ECD and LC-Electrospray ionization (ESI)-MS/MS method was examined. As a result, the median values of µmol 3-HPMA/g Creatinine (Cre) in urine obtained by column-switching HPLC-ECD and LC-MS/MS were 2.19 ± 2.12 µmol/g Cre and 2.13 ± 3.38 µmol/g Cre, respectively, and the calibration curve (y = 1.5171x – 1.007) exhibited good linearity within a defined range (r2 = 0.907). These results indicate that the combination of column-switching HPLC and ECD is a powerful tool for the specific, reliable detection of 3-HPMA in urine.