HPLC-UV法测定大鼠血浆中坎地沙坦的质量浓度及胃肠道吸收的研究

Determination of candesartan in rat plasma by HPLC-UV method and study on the gastrointestinal absorption

目的建立灵敏、简便的HPLC-UV法测定大鼠血浆中坎地沙坦的质量浓度,用于研究坎地沙坦酯固体脂质纳米粒在大鼠胃肠道的吸收情况。方法采用Eclipse XCB-C18色谱柱(150 mm×4.6 mm,5μm),流动相为水(体积分数0.1%磷酸,体积分数0.1%三乙胺,pH值2.7)-乙腈(体积比42∶58),流速为1.0 mL·min-1,检测波长为254 nm。结果测定坎地沙坦的线性范围在0.01～1 mg·L-1时,回归方程为A=7.028ρ+4.200×10-2(r=0.999 8);线性范围在0.3～30 mg·L-1时,回归方程为A=0.237ρ+1.00×10-3(r=0.999 2),定量下限达到10μg.L-1。日内、日间RSD值均小于10.0%,提取回收率大于75%。该方法用于评价坎地沙坦酯固体脂质纳米粒及原料药在大鼠胃肠道的吸收。结论该方法灵敏、简单、可靠,可用于测定血浆中坎地沙坦的质量浓度。与原料药相比,坎地沙坦酯固体脂质纳米粒在胃和小肠部位的吸收均有显著提高。

Objective To establish a sensitive and convenient HPLC method for the determination of the plasma concentration of candesartan and investigate the gastrointestinal absorption of candesartan cilexetil loaded solid lipid nanoparticles（SLNs）in rats.Methods The determination was performed on HPLC system with Eclipse XDB-C18 column（150 mm×4.6 mm,5 μm）.The mobile phase consisted of water（0.1%phosphoric acid and 0.1% triethylamine,pH 2.7）and acetonitrile（V∶ V=42∶ 58）at a flow rate of 1.0 mL · min-1,and the detection wavelenth was set at 254 nm.EXP3174 was used as the internal standard.The absorption of CSLNs in stomach and intestine was performed by intragastric and intraduodenal administration,respectively,in comparison with that of free drug suspension.Results The standard regression equations of area ratio（A）to concentration（ρ）were as follows：A=7.028ρ＋4.200×10-2,r=0.999 8（ρ=0.01-1 mg · L-1）;A=0.237ρ＋1.00×10-3,r=0.999 2（ρ=0.3-30 mg · L-1）,and the lower limit of quantification（LLOQ）was 10 μg · L-1.The RSDs of intra-and inter-day were less than 10.0%,and the extraction recovery was more than 75%.The validated method was successfully applied to the comparative absorption of stomach and intestine after administration of SLN and free drug suspension.It was found that the absorption of SLNs was remarkably enhanced in stomach and intestine compared with that of free drug suspension.Conclusions The HPLC method is easy,sensitive and reliable for the determination of candesartan in rat plasma.SLNs are potential for enhancing the gastrointestinal absorption of insoluble candesartan cilexetil in rats.