Xu Qianqian, Li Jichang, Shen Zhiqiang, Guo Shijin, Wang Yubo, Li Feng
Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou 256600, China Shandong Lvdu Ante Veterinary Drug Industry Co., Ltd, Binzhou 256600, China
College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
J Chromatogr Sci. 2014 Oct;52(9):999-1004. doi: 10.1093/chromsci/bmt142. Epub 2013 Sep 26.
An HPLC-MS method has been developed and validated for the quantitative determination of milbemycin oxime (MBO) in dog plasma. The developed method has been then applied in in vivo clinical studies to obtain pharmacokinetics of MBO in blood after its oral administration. Samples were extracted using solid-phase extraction (SPE). Sample proteins were precipitated with acetonitrile (ACN) and sodium chloride (NaCl) and then diluted with methanol and water. Calibration standards were prepared by using plasma matrix and following the same SPE procedure. Chromatographic separation was performed on a Waters C18 packed column (3.5 μm particles diameter; 3 × 100 mm) with a C18 guard column (3.5 μm particles diameter; 3 × 20 mm). The mobile phase was an 85:15 (v/v) mixed solution of ACN and 5 mM ammonium acetate. The calibration curve was linear over a concentration range of 2.0-500 ng/mL with a limit of quantitation of 2.0 ng/mL. The oral administration of a pellet of 2.5 mg MBO produced blood concentrations ranging from 6.10 ± 0.92 to 78.81 ± 4.38 ng/mL within 6 h, with a terminal half-time of 11.66 ± 0.93 h. This study determined the suitability of the herein proposed method to investigate the pharmacokinetics of MBO after oral administration.
已开发并验证了一种用于定量测定犬血浆中米尔贝肟（MBO）的高效液相色谱-质谱（HPLC-MS）方法。然后将所开发的方法应用于体内临床研究，以获取口服给药后MBO在血液中的药代动力学。样品采用固相萃取（SPE）进行提取。样品蛋白用乙腈（ACN）和氯化钠（NaCl）沉淀，然后用甲醇和水稀释。校准标准品采用血浆基质并遵循相同的SPE程序制备。色谱分离在Waters C18填充柱（粒径3.5μm；3×100mm）和C18保护柱（粒径3.5μm；3×20mm）上进行。流动相为ACN与5mM醋酸铵的85:15（v/v）混合溶液。校准曲线在2.0-500ng/mL的浓度范围内呈线性，定量限为2.0ng/mL。口服2.5mg MBO丸剂后，6小时内血药浓度范围为6.10±0.92至78.81±4.38ng/mL，终末半衰期为11.66±0.93小时。本研究确定了本文所提出的方法用于研究口服给药后MBO药代动力学的适用性。
