GC测定异维A酸中吡啶和乙酸

Determination of Pyridine and Acetic Acid in Isotretinoin by GC

目的建立气相色谱法(GC)测定异维A酸原料药中吡啶和乙酸的方法。方法色谱柱为DB-WAXETR毛细管柱(30 m×0.320 mm,1.00μm),进样口温度220℃,氢火焰离子化检测器温度250℃;载气为氮气,流速2.0 mL·min^(-1),分流比5∶1。直接进样,初始温度为110℃,保持12 min,以50℃·min^(-1)升温至220℃,保持5 min,进样体积为1.0μL。结果吡啶和乙酸的线性范围分别为4.74～94.8μg·mL^(-1)、25.4～508.0μg·mL^(-1),线性方程分别为Y=1.953 2X-0.722 5(r=0.999 5)、Y=2.334X-4.108 9 (r=0.999 6);平均回收率分别为89.69%、84.59%,RSD分别为5.5%、3.3%;检测限分别为1.23,0.84μg·mL^(-1),定量限分别为4.09,2.79μg·mL^(-1)。结论建立的气相色谱法适用于异维A酸原料药中吡啶和乙酸测定。

OBJECTIVE To establish a gas chromatography method for determination of pyridine and acetic acid in Isotretinoin.METHODS DB-WAXETR( 30 m× 0.320 mm,1.00 μm) capillary column was used. The injection port temperature was 220 ℃ and FID temperature was 250 ℃.Nitrogen was the carrier gas with flow rate of 2. 0 mL·min^-1 and split ratio 5 ∶ 1. Samples were tested by direct injection.The oven temperature was initially held at 110 ℃ for 12 min and then programmed to 220 ℃ at 50 ℃·min^-1 and held for5 min.The injection volumn was 1.0 μL. RESULTS The linear ranges of pyridine and acetic acid were respectively 4.74-94.8 μg·mL^-1,25.4-508.0 μg·mL^-1 and regression equations were Y = 1.953 2 X-0.722 5( r = 0.999 5),Y = 2.334 X-4.108 9( r = 0.999 6).The average recoveries were 89.69%,84.59% and RSDs were 5.5%,3.3%. LODs were 1.23,0.84 μg·mL^-1 and LOQs were 4. 09,2.79 μg·mL^-1.CONCLUSION The method can be applied in determination of pyridine and acetic acid in Isotretinoin.