Wang Peng, Qi Meiling, Jin Xin
Shenyang Pharmtech Institute of Pharmaceuticals, Shenyang 110016, China.
J Pharm Biomed Anal. 2005 Sep 15;39(3-4):618-23. doi: 10.1016/j.jpba.2005.04.006.
A liquid chromatography-mass spectrometry (LC-MS) method for the determination of roxithromycin in rat lung tissue is described. Liquid-liquid extraction was adopted for sample preparation with recoveries from 72.5 to 76.9% at levels of 0.1, 5.0 and 20.0 microg/ml. Chromatographic separation was performed on a C18 column using a mixture of methanol, water and formic acid (80:20:1, v/v/v) as mobile phase delivered at a flow rate of 0.5 ml/min. Positive selected ion monitoring (SIM) mode was used for the quantification of roxithromycin at m/z 837.7 and clarithromycin (internal standard) at m/z 748.7. The linearity was obtained over the concentration range of 0.05-20.0 microg/ml and the lower limit of quantification was 0.05 microg/ml. For each QC level of roxithromycin, the intra- and inter-day precisions relative standard deviation (R.S.D.) were less than 4.1 and 7.5%, respectively, and accuracy (RE) was +/-10.0%. The proposed LC-MS method has been successfully used for the determination of roxithromycin in rat lung tissue after oral administration of roxithromycin formulations to 44 SD rats. The present study demonstrates that the concentration of roxithromycin in rat lung tissues can be significantly increased by ambroxol when they are formulated in combination.
描述了一种用于测定大鼠肺组织中罗红霉素的液相色谱-质谱（LC-MS）方法。采用液-液萃取法进行样品制备，在0.1、5.0和20.0μg/ml水平下回收率为72.5%至76.9%。色谱分离在C18柱上进行，以甲醇、水和甲酸（80:20:1，v/v/v）的混合物作为流动相，流速为0.5 ml/min。采用正离子选择离子监测（SIM）模式，以m/z 837.7定量罗红霉素，以m/z 748.7定量克拉霉素（内标）。在0.05-20.0μg/ml浓度范围内获得线性关系，定量下限为0.05μg/ml。对于罗红霉素的每个质量控制水平，日内和日间精密度相对标准偏差（R.S.D.）分别小于4.1%和7.5%，准确度（RE）为±10.0%。所提出的LC-MS方法已成功用于对44只SD大鼠口服罗红霉素制剂后大鼠肺组织中罗红霉素的测定。本研究表明，氨溴索与罗红霉素联合制剂时，大鼠肺组织中罗红霉素的浓度可显著增加。
