Cham B E, Ross-Lee L, Bochner F, Imhoff D M
Ther Drug Monit. 1980;2(4):365-72.
Plasma acetylsalicylic acid and salicylic acid are assayed by a specific, rapid, and sensitive high performance liquid chromatographic procedure. The plasma samples are treated with physostigmine to inhibit esterase activity that otherwise will promote enzymatic hydrolysis of acetylsalicylic acid to salicylic acid. Conditions are chosen such that the total in vitro hydrolysis of acetylsalicylic acid is minimized to less than 5%. Plasma samples are deproteinated with methylcyanide. Acetylsalicylic acid and salicylic acid are separated by elution with a mixture of methanol, acetic acid, and water on a reversed-phase octadecyl silane column and detected by ultraviolet absorption. Quantitation is achieved by measuring absolute peak heights. Recovery and repeatability studies are good. No interference was observed when 50 drugs were also present in the various plasma samples. Concentrations of acetylsalicylic acid and salicylic acid can be obtained within 20 min of receipt of the blood specimens. Pharmacokinetic parameters obtained by this method after a single oral dose of 900 mg soluble, effervescent acetylsalicylic acid in normal healthy subjects suggest that absorption, distribution, and elimination of acetylsalicylic acid are rapidly occurring events.
血浆中的乙酰水杨酸和水杨酸通过一种特异、快速且灵敏的高效液相色谱法进行测定。血浆样本用毒扁豆碱处理以抑制酯酶活性，否则酯酶会促进乙酰水杨酸酶解为水杨酸。选择合适的条件使乙酰水杨酸的体外总水解率降至最低，低于5%。血浆样本用乙腈进行蛋白沉淀。乙酰水杨酸和水杨酸在反相十八烷基硅烷柱上用甲醇、乙酸和水的混合物洗脱分离，并用紫外吸收进行检测。通过测量绝对峰高进行定量。回收率和重复性研究结果良好。当各种血浆样本中还存在50种药物时，未观察到干扰。在收到血样后20分钟内即可获得乙酰水杨酸和水杨酸的浓度。在正常健康受试者中单次口服900毫克可溶性泡腾乙酰水杨酸后，用该方法获得的药代动力学参数表明，乙酰水杨酸的吸收、分布和消除都是快速发生的过程。
