Fosinopril diacid is an angiotensin converting enzyme inhibitor with efficient antihypertensive action. It is an active metabolic product formed in the body from hydrolysis of its prodrug Fosinopril. A sensitive, rapid method with high recovery for Fosinopril diacid from human plasma was developed. Solid‐phase extraction technique employing Waters Oasis SPE cartridges gave clean samples with very high recovery of 97%. The analyte along with its internal standard (Benazepril hydrochloride) were chromatographed on an XTerra RP₈ column (4.6 × 50 mm, 5 μm) using methanol–ammonium acetate buffer (10 mm; 90:10, v/v) as the mobile phase. A triple quadrupole mass spectrometer equipped with electrospray ionization source operated in the negative ion mode was used for detection. Multiple reaction monitoring scan mode was used for monitoring the transitions from m/z 434.00 → 237.15 for Fosinopril diacid and m/z 423.10 → 174.00 for Benazepril hydrochloride. Beer–Lambert’s law was obeyed in the range of 0.50–1,500.00 ng/ml (r = 0.9993). The stability of the drugs in human plasma and in stock solution was proved by performing stability tests as per US Food and Drug Administration guidelines. The method was successfully applied for a bioequivalence study of Fosinopril diacid in 36 healthy, adult, male volunteers under fasting conditions.

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一种灵敏有效的LC-MS / MS方法用于血浆中福辛普利二酸的生物分析及其在人体生物等效性研究中的应用

福辛普利二酸是一种具有有效降压作用的血管紧张素转化酶抑制剂。它是前药福辛普利水解后在体内形成的活性代谢产物。开发了一种灵敏，高回收率的人血浆中福辛普利二酸的方法。采用沃特世Oasis SPE柱的固相萃取技术可得到干净的样品，回收率极高，达到97％。使用甲醇-醋酸铵缓冲液（10 m m； XTerra RP ₈色谱柱（4.6×50 mm，5μm））对分析物及其内标（盐酸贝那普利）进行色谱分离。90：10，v / v）作为流动相。使用配备有以负离子模式运行的电喷雾电离源的三重四极杆质谱仪进行检测。多反应监测扫描模式用于监测福辛普利二酸的m / z 434.00→237.15和盐酸贝那普利的m / z 423.10→174.00的转变。遵循比尔-兰伯特定律在0.50-1,500.00 ng / ml（r = 0.9993）。通过按照美国食品和药物管理局的指导进行稳定性测试，证明了药物在人血浆和原液中的稳定性。该方法已成功地用于禁食条件下福辛普利二酸在36名健康，成年，男性志愿者中的生物等效性研究。