Aluri J B, Stavchansky S
Pharmaceutics Division, College of Pharmacy, University of Texas at Austin 78712.
J Pharm Biomed Anal. 1993 Sep;11(9):803-8. doi: 10.1016/0731-7085(93)80072-9.
A sensitive and specific liquid chromatography (LC) procedure was developed and validated for the determination of guaifenesin in human plasma in the presence of pseudoephedrine. Guaifenesin was extracted from plasma at pH 6.9-7.1 using methanol-methylene chloride (5:95, v/v) containing the internal standard mephenesin and pseudoephedrine. The organic layer was separated and evaporated to dryness and the residue reconstituted with the mobile phase containing methanol-acetonitrile-phosphate buffer (0.05 M) (11:11:78, v/v/v) containing 4 mM heptane sulphonic acid and 1% glacial acetic acid. The separation was performed on a mu Bondapak C18 column. The flow rate was 1.0 ml min-1. The retention times for guaifenesin and mephenesin were 7.9 and 15.7 min, respectively. Linearity of response was observed in the concentration ranges of 50-1000 ng ml-1 and 1-4 micrograms ml-1. Accuracy was within 15.4% of the true value for the inter-day and intra-day analysis. The precision, as measured by the RSD, ranged from 4.8 to 8.7% for intra-day. The reproducibility of inter-day ranged from 5.0 to 8.4%. The per cent recovery from plasma ranged from 88.6 to 97.6. Data are presented to illustrate the practicality of the method for the evaluation of guaifenesin plasma levels in the presence of pseudoephedrine after multiple oral administration of two sustained release tablets containing 600 mg of guaifenesin per tablet to six male healthy volunteers. The mean half-life of guaifenesin in human subjects was found to be 2.88 h and ranged from 1.36 to 5.25 h.
建立了一种灵敏且特异的液相色谱（LC）方法，并对其进行了验证，用于在伪麻黄碱存在的情况下测定人血浆中的愈创甘油醚。使用含有内标美芬辛和伪麻黄碱的甲醇 - 二氯甲烷（5:95，v/v）在pH 6.9 - 7.1条件下从血浆中提取愈创甘油醚。分离有机层并蒸发至干，残留物用含有甲醇 - 乙腈 - 磷酸盐缓冲液（0.05 M）（11:11:78，v/v/v）的流动相复溶，该流动相含有4 mM庚烷磺酸和1%冰醋酸。在μ Bondapak C18柱上进行分离。流速为1.0 ml min-1。愈创甘油醚和美芬辛的保留时间分别为7.9和15.7分钟。在50 - 1000 ng ml-1和1 - 4 μg ml-1的浓度范围内观察到响应线性。日间和日内分析的准确度在真实值的15.4%以内。以相对标准偏差（RSD）衡量，日内精密度范围为4.8%至8.7%。日间重现性范围为5.0%至8.4%。血浆回收率范围为88.6%至97.6%。给出数据以说明该方法在六名男性健康志愿者多次口服两片每片含600 mg愈创甘油醚的缓释片后，在伪麻黄碱存在的情况下评估愈创甘油醚血浆水平的实用性。发现愈创甘油醚在人体受试者中的平均半衰期为2.88小时，范围为1.36至5.25小时。
