司替戊醇及其自纳米乳在大鼠血浆和脑组织中的药物浓度比较

戴秋阳 汤米 张培炎 包小峰 陈勇

摘 要 目的：建立測定大鼠血浆和脑组织中司替戊醇（STP）质量浓度的方法，并比较STP及其自纳米乳在血浆、脑组织中的药物浓度。方法：以占吨酮为内标，采用高效液相色谱-荧光检测法（HPLC-FLR）测定。色谱柱为Diamonsil C18，流动相为乙腈-25 mmol/L KH2PO4水溶液[44 ∶ 56（V/V），pH 2.6]，流速为1.5 mL/min，激发波长为210 nm，发射波长为400 nm，柱温为30 ℃，进样量为10 μL。将36只大鼠随机分为两组，每组18只，分别灌胃STP自纳米乳和STP混悬液（40 mg/kg，均以STP计）。于给药后0.5、1、2 h时采集大鼠血液和脑组织样品（各时间点每组各6只），经乙腈沉淀蛋白（脑组织需先进行匀质）等处理后，采用上述色谱条件检测STP的质量浓度并比较。结果：STP在血浆、脑组织中药物浓度检测的线性范围均为0.02～8.00 μg/mL（r分别为0.999 6、0.999 4），定量下限均为0.02 μg/mL;日内、日间RSD均小于5%，提取回收率和方法回收率均不低于90%。与STP混悬液组比较，STP自纳米乳组大鼠各时间点的血药浓度（给药后1 h除外）、脑组织中药物浓度（给药后2 h除外）均显著升高（P<0.05），且两者（以STP自纳米乳为对象）具有明显的线性关系。结论：所建HPLC-FLR法的灵敏度、精密度较高，可用于研究STP及其自纳米乳在大鼠血浆和脑组织中的分布情况;将STP制成自纳米乳后，其在血浆、脑组织中的药物浓度明显提高。

关键词 司替戊醇;自纳米乳;高效液相色谱-荧光检测法;体内药物分布;血浆;脑组织

中图分类号 R969.1 文献标志码 A 文章编号 1001-0408（2021）03-0273-05

DOI 10.6039/j.issn.1001-0408.2021.03.04

ABSTRACT   OBJECTIVE： To establish a method for determining stiripentol （STP） concentration in plasma and brain of rats， and to compare the concentrations of STP and its self-nanoemulsifying drug delivery system （STP-SNEDDS） in plasma and brain. METHODS： Using xanthone as internal standard， HPLC-fluorescence （HPLC-FLR） method was adopted. The determination was performed on Diamonsil C18 column with mobile phase consisted of acetonitrile-25 mmol/L KH2PO4 solution [44 ∶ 56（V/V）， pH 2.6] at a flow rate of 1.5 mL/min; the excitation and emission wavelengths were 210 nm and 400 nm， respectively; the column temperature was 30 ℃; the sample size was 10 μL. Totally 36 rats were randomly divided into 2 groups， with 18 rats in each group. They were given STP-SNEDDS and STP suspension （40 mg/kg， by STP） intragastrically. Blood and brain tissue samples were collected at 0.5， 1， 2 h after administration （6 rats in each group at different time point）. After the protein was precipitated by acetonitrile （brain tissue should be homogenized）， the concentrations of STP were determined by the above chromatographic conditions. RESULTS： The linear ranges of STP concentration in plasma and brain tissue were 0.02-8.00 μg/mL （r were 0.999 6， 0.999 4， respectively）. The limits of quantitation were both 0.02 μg/mL. The inter-day and intra-day RSDs were all less than 5%. The extraction recovery and method recovery were all no less than 90%. Compared with STP suspension group， the plasma concentration （except for 1 h after administration） and cerebral concentration （except for 2 h after administration） of STP in STP-SNEDDS group were all significantly increased （P<0.05）， showing significant linear relationship between them （for STP-SNEDDS）. CONCLUSIONS： Established HPLC-FLR method presents high accuracy and precision， and can be used for the distribution of STP and STP-SNEDDS in plasma and brain. The concentration of STP in plasma and brain tissue is increased after STP is made into SNEDDS.

KEYWORDS   Stiripentol; Self-nanoemulsifying drug delivery system; HPLC-fluorescence method; Drug distribution in vivo; Plasma; Cerebral tissue

司替戊醇（Stiripentol，STP）用于治疗2周岁及以上的Dravet综合征患者的癫痫发作[1-2]。该药水溶性差[3]，在胃肠道中溶出缓慢且不完全，在酸性环境下稳定性差，由于上述经口吸收的局限性，使得该药的日口服剂量较高[4]。自纳米乳化药物递送系统（Self-nanoemulsi- fying drug delivery system， SNEDDS）由油相、表面活性剂、助表面活性剂和药物构成，在胃肠道中可自发形成纳米尺寸的水包油型乳液，从而增加机体对难溶性药物的吸收[5]。本……