LC-ESI-MS测定大鼠血浆中同型半胱氨酸的含量

目的: 建立LC-ESI-MS法测定大鼠体内的同型半胱氨酸(HCY)。 方法: 色谱柱为Zorbax SB-C₁₈(2.1 mm×100 mm,3.5 μm),乙腈-水(40∶ 60)为流动相,流速为0.3 mL·min^-1,柱温为30 ℃。ESI(电喷雾离子源),正离子检测,雾化气压力设为172.375 kPa;干燥气(N₂)流速设为7 L·min^-1,干燥气温度设为350 ℃, ⁺,m/z 136。 结果: HCY在2.5~100 μmol·L^-1范围内线性关系良好,线性方程C=0.0079X-8.1011,r=0.9981,最低检测限为1 μmol·L^-1。HCY日内及日间精密度RSD均低于6%。12周龄的Wistar-Kyoto大鼠,自发性高血压大鼠体内HCY的浓度分别为(9.57±3.49) μmol·L^-1和(11.59±3.13) μmol·L^-1。 结论: 该法操作简便、快速,灵敏度高,可用于大鼠体内HCY的检测。

Objective: To establish an LC-ESI-MS method for determination of homocysteine in rat plasma. Methods: A Zorbax SB-C₁₈(2.1 mm×100 mm,3.5 μm) column was used,with mobile phase of methanol-water (40∶ 60),flow rate 0.3 mL·min^-1,column temperature 30 ℃.Electrospray ionization (ESI) source was applied and operated in positive ion mode.The pressure of atomizing gas set up 172.375 kPa;the flow rate of drying gas(N₂) was 7 L·min^-1 and the temperature was 350 ℃, ⁺,m/z 136. Results: The calibration curve of homocysteine in plasma was linear in the concentration range of 2.5-100 μmol·L^-1.C= 0.0079X-8.1011,r=0.9981.The LLOQ was 1 μmol·L^-1.The precision of intra-day and inter-day was both below 6%.The concentration of HCY in 12 weeks Wistar-Kyoto and SHR (Spontaneously hypertensive rats) were (9.57±3.49) μmol·L^-1 and (11.59±3.13) μmol·L^-1,respectively. Conclusion: The analytical method for homocysteine is accurate,sensitive and suitable for analysis of rat plasma concentration.