Prueksaritanont T, Sittichai N, Prueksaritanont S, Vongsaroj R
Drug Analysis Division, Department of Medical Sciences, Yod-se, Bangkok.
J Chromatogr. 1989 May 5;490(1):175-85. doi: 10.1016/s0378-4347(00)82772-3.
A sensitive high-performance liquid chromatographic method was developed for the simultaneous determination of ranitidine and its metabolites, ranitidine N-oxide, ranitidine S-oxide and desmethylranitidine, in human plasma and urine. For the plasma analysis, 1-ml plasma samples spiked with phenylpyramidol as the internal standard were extracted at basic pH with acetonitrile-ethyl acetate (3:2, v/v). After evaporation and reconstitution, the samples were chromatographed on a cation-exchange column, with a mobile phase of 0.1 M sodium acetate buffer (pH 5)-acetonitrile-tetrahydrofuran (56.5:36:7.5, v/v) and ultraviolet detection at 320 nm. The extraction recoveries were 99.8, 30.4, 74.2 and 80.2% and the detection limits were 5, 15, 10 and 4 ng/ml for ranitidine, ranitidine N-oxide, ranitidine S-oxide and desmethylranitidine, respectively. For the urine analysis, a simple deproteinization with an equal volume of acetonitrile was satisfactory for sample preparation. The applicability of this method for the pharmacokinetic study of ranitidine following oral administration was demonstrated.
建立了一种灵敏的高效液相色谱法，用于同时测定人血浆和尿液中的雷尼替丁及其代谢产物雷尼替丁N-氧化物、雷尼替丁S-氧化物和去甲基雷尼替丁。对于血浆分析，将加有苯吡醇作为内标的1 ml血浆样品在碱性pH条件下用乙腈-乙酸乙酯（3:2，v/v）萃取。蒸发和复溶后，样品在阳离子交换柱上进行色谱分析，流动相为0.1 M乙酸钠缓冲液（pH 5）-乙腈-四氢呋喃（56.5:36:7.5，v/v），并在320 nm处进行紫外检测。雷尼替丁、雷尼替丁N-氧化物、雷尼替丁S-氧化物和去甲基雷尼替丁的萃取回收率分别为99.8%、30.4%、74.2%和80.2%，检测限分别为5、15、10和4 ng/ml。对于尿液分析，用等体积乙腈进行简单的去蛋白处理即可满足样品制备要求。该方法在雷尼替丁口服给药的药代动力学研究中的适用性得到了验证。
