Cataracts are the most common cause of blindness worldwide affecting tens of millions of people. Here, we report a simple, rapid, sensitive and specific method by ultra performance liquid chromatography–tandem mass spectrometry with the electrospray ionization mode (UPLC–ESI-MS/MS) for quantitation of lanosterol, a possible effective drug for cataracts, in the vitreous humor of rabbits after ocular administration. The injected lanosterol was prepared by dispersing lanosterol molecules into the poly-(dl-lactic acid-co-glycolic acid)–poly(ethylene glycol)–poly-(dl-lactic acid-co-glycolic acid) (PLGA–PEG–PLGA) thermogel solution. The analyte and internal standard (IS, panaxadiol) were extracted by the simple protein precipitation with methanol. The chromatographic separation used an Agilent RRHD SB-C₁₈ column with a methanol mobile phase containing 50 mM of ammonium acetate aqueous solution (with 0.1% formic acid) (95:5, v/v). The protonated analyte was quantitated in positive ionization by multiple reaction monitoring (MRM) with a mass spectrometer. The mass transitions m/z 443.5 → 235 and m/z 461 → 127 were used to measure the analyte and IS, respectively. The assay exhibited a linear dynamic range of 1–1250 ng mL⁻¹ for lanosterol in vitreous samples. The lower limit of quantitation (LLOQ) was 1 ng mL⁻¹ with a relative standard deviation (RSD) of less than 15%. Acceptable precision and accuracy were obtained for concentrations over the standard curve ranges. A run time of 5 min per sample offered a throughput of more than 200 samples per day. This validated method was used to analyze vitreous samples of New Zealand white rabbits for pharmacokinetic studies. The results provided useful information on pharmacological action mechanism of lanosterol and were meaningful for cataract treatment among the elderly population.

白内障是全世界致盲的最普遍原因，影响了成千上万人。在这里，我们报告了一种通过超高效液相色谱-串联质谱联用电喷雾电离模式（UPLC-ESI-MS / MS）的简单，快速，灵敏和特异的方法，用于定量分析其中的一种有效的白内障药物羊毛甾醇。眼给药后兔的玻璃体液。注射用的羊毛甾醇是通过将羊毛甾醇分子分散到聚（dl-乳酸-共-乙醇酸）-聚（乙二醇）-聚- （dl-乳酸-共-乙醇酸（PLGA–PEG–PLGA）热凝胶溶液。通过用甲醇进行简单的蛋白质沉淀来提取分析物和内标物（IS，人参二醇）。色谱分离使用Agilent RRHD SB-C ₁₈色谱柱，甲醇流动相包含50 mM乙酸铵水溶液（含0.1％甲酸）（95：5，v / v）。通过质谱仪的多反应监测（MRM），在正电离中对质子化的分析物进行定量。质量变迁m / z 443.5→235和m / z 461→127分别用于测量分析物和IS。该测定法显示的线性动态范围是1–1250 ng mL ^-1用于玻璃样样品中的羊毛甾醇。定量下限（LLOQ）为1 ng mL ^-1，相对标准偏差（RSD）小于15％。对于标准曲线范围内的浓度，获得了可接受的精度和准确度。每个样品5分钟的运行时间提供了每天200多个样品的通量。该经过验证的方法用于分析新西兰白兔的玻璃体样品，以进行药代动力学研究。该结果提供了有关羊毛甾醇的药理作用机理的有用信息，对于老年人群白内障的治疗具有重要意义。