为了降低丙交酯乙交酯共聚物(PLGA)对单体残留量测定结果的影响,以二氯甲烷为溶剂,正己烷为沉淀剂,进行了题示项目的研究。取样品约0.1 g,加7 mL二氯甲烷(溶剂)溶解后,置于10 mL容量瓶中,加正己烷(沉淀剂)稀释至刻度。摇匀并离心后,取上清液作为供试品溶液。以Agilent HP-INNOWax毛细管色谱柱进行分离,氢火焰离子化检测器(FID)进行检测,采用气相色谱法测定上述溶液中乙交酯和丙交酯两种单体的含量。结果表明,采用溶解沉淀法,有效降低直接进样法所带来的系统污染,也大幅提高了检测准确度。两种单体的质量浓度在0.005~0.060 g·L^-1内均与对应的峰面积呈线性关系,乙交酯和丙交酯的检出限(3S/N)分别为2.0,1.0 mg·L^-1,加标回收率分别为97.0%,101%。对混合对照品溶液和供试品溶液进行精密度试验,测定值的相对标准偏差(n=6)均小于3.0%。方法用于分析3批样品,两种单体残留量均小于0.050%。

In order to reduce the effect of poly(lactide-co-glycolide) (PLGA) on the determination of monomer residue, the work as mentioned by the article was done, using dichloromethane as solvent and n-hexane as precipitant. About 0.1 g of sample was dissolved in 7 mL dichloromethane (solvent), and then the solution was placed into a 10 mL-volumetric flask and n-hexane (precipitant) was added to dilute to the scale. After shaking and centrifuging, the supernatant was taken as the test solution. Agilent HP-INNOWax capillary column was used for separation and FID was used for detection, and the two monomers of glycolide and lactide in the above solution were determined by gas chromatography. As shown by the results, the dissolving-precipitation method could effectively reduce the system pollution caused by direct injection method and greatly improve the detection accuracy. Linear relationships between values of peak area and mass concentration of two monomers were found in the range of 0.005-0.060 g·L^-1, with detection limits (3S/N) of 2.0 mg·L^-1 for glycolide and 1.0 mg·L^-1 for lactide. The spiked recoveries were 97.0% and 101%, respectively. The precision test of the mixed reference solution and the test solution were carried out, with RSDs (n=6) of the determined values less than 3.0%. The method was applied to analysis of three batches of samples, and the residues of two monomers were less than 0.050%.