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目的 分别采用GC顶空进样和液体进样器进样方式测定碘酊中乙醇的含量,并对2种进样方式进行比较研究.方法 采用Aglient DB-ALC1型气相色谱柱(30 m×0.53 mm,3.0 μm),FID检测器温度为250℃,柱温为80℃,进样口温度为200℃,N2载气,柱流速为5 mL·min-1,辅助加热区115℃.以叔丁醇为内标进行定量,采用顶空和液体2种进样方式,液体进样量1.0μL,顶空进样量1.0 mL.结果 顶空进样时,乙醇在15.78～63.12 mg·mL-1线性关系良好,Y=3.558 9X-0.341 3(R2=0.9989);回收率≥96.55％,RSD≤4.30％;日内精密度RSD≤3.86％;液体选样时,乙醇在15.78～63.12 mg·mL-1线性关系良好,Y=0.01 5X-0.006(R2=0.999 5);回收率≥97.8％,RSD≤3.22％;日内精密度RSD≤3.85％.结论 这2种方法均能准确地测量碘酊中乙醇的浓度,顶空进样法耗时较长但灵敏度比直接进样更高,对色谱柱的污染也较小,2种方法均能用于碘酊中乙醇含量的测定.“,”OBJECTIVE To establish and compare methods for detection of the ethanol in the iodine tincture by GC using direct injection and head-space injection.METHODS The ethanol in the iodine tincture was determined by GC with Agilent DB-ALC1 capillary column(30 m×0.53 mm,3.0 μm) and FID detector,using nitrogen as the carries gas.The injector temperature was 200 ℃;the detector temperature was 250 ℃;the column temperature was 80 ℃.The flow rate of N2 was 5 mL·min-1,and the auxiliary heating temperature was 115 ℃.Tertbutyl alcohol was used as the internal standard,1.0 mL sample was injected by headspace injector and 1.0 μL by direct injection.RESULTS With head-space injection,the calibration curves of ethanol had good linear relationship within 15.78-63.12 mg·mL-1,Y=3.558 9X-0.341 3 (R2=0.998 9);the recovery was ≥96.55％;RSD was ≤4.30％;the within-day precision was ≤3.86％.The calibration curves of ethanol between concentration of 15.78-63.12 mg·mL-1 by direct injection was Y=0.015X-0.006(R2=0.999 5),the recovery was ≥97.8％(RSD≤3.22％);the within-day precision was ≤3.85％.CONCLUSION Both two methods are accurate and reliable,and can be used for the determination of the concentration of ethanol in the iodine tincture,and the method using head-space injection has more sensitive,less disturb and long analysis time than direct injection.