Kuschak D, Mauss S, Schmutz G, Gantke B
Medical Laboratories Düsseldorf, Germany.
Clin Lab. 2001;47(9-10):471-7.
Protease inhibitors are known by their inhibition of a viral protease that leads to production of immature and non-infectious virus particles. The novel protease inhibitor KALETRA is a co-formulation of lopinavir and ritonavir. Ritonavir reduces the metabolization of lopinavir by the cytochrome P450 3A4 isoenzyme which leads to markedly increased plasma levels of lopinavir(4). A new rapid and sensitive HPLC method for the simultaneous determination of lopinavir, indinavir, amprenavir, saquinavir, ritonavir and nelfinavir in human plasma has been developed. An aliquot of 500 microl plasma, spiked with internal standard, was extracted with 500 microl 0.1 M ammonium hydroxide solution and 5 ml tert. -butyl ether. After drying under a nitrogen stream, the residue was redissolved in an eluent consisting of 50 mM phosphate buffer, pH 5.40 and acetonitrile (50:50, v/v). Chromatographic separation was accomplished on a C-18 column using a non-linear gradient elution and ultraviolet detection at 215 nm.
蛋白酶抑制剂因其对病毒蛋白酶的抑制作用而闻名，这种抑制作用会导致产生未成熟且无感染性的病毒颗粒。新型蛋白酶抑制剂克力芝是洛匹那韦和利托那韦的复方制剂。利托那韦可减少细胞色素P450 3A4同工酶对洛匹那韦的代谢，从而使洛匹那韦的血浆水平显著升高（4）。已开发出一种新的快速灵敏的高效液相色谱法，用于同时测定人血浆中的洛匹那韦、茚地那韦、安普那韦、沙奎那韦、利托那韦和奈非那韦。取500微升加有内标的血浆样品，用500微升0.1 M氢氧化铵溶液和5毫升叔丁基醚萃取。在氮气流下干燥后，残渣重新溶解于由50 mM磷酸盐缓冲液（pH 5.40）和乙腈（50:50，v/v）组成的洗脱液中。在C-18柱上进行色谱分离，采用非线性梯度洗脱，并在215 nm处进行紫外检测。
