The study aimed to prepare the thermosensitive in situ gel of ciprofloxacin lactate(CPFL)and evaluate its sustained in vitro release.The in situ thermosensitive gel of CPFL was prepared with poloxamer 407(P407)and poloxamer 188(P188)as thermosensitive materials by using cold method.Gelation temperature(GT)of various concentration poloxamer solutions were all investigated with the method of inversion of test tube.Gel erosion of the in situ gels and release of CPFL from the in situ gels were investigated by membrane free method at 37 ℃ under agitation.The content of CPFL from the thermosensitive in situ gel was determined by ultraviolet spectrophotometry.The best compositions were selected with release time and GT.The results showed that the best compositions were 0.024 g·mL-1 P407+0.02 g·mL-1 P188+0.08 g·mL-1 CPFL+0.000 3 g·mL-1 EDTA-2Na+0.001 5 g·mL-1 NaHSO3+0.000 1 g·mL-1 benzalkonium bromide.The in situ gel was fluid at room temperature,and gel phase transition occurred at body temperature.The cumulative release of drug achieved 84.23% at 11 h without burst phenomenon.It followed the Higuchi kinetic equation.The results demonstrate that the preparation method of the CPFL thermosensitive in situ gel is appropriate and the drug loading and release in vitro all can reach the expected request.

建立乳酸环丙沙星泊洛沙姆原位凝胶中乳酸环丙沙星含量测定的高效液相色谱法。以流动相为参比溶液,在波长200～400 nm段用紫外分光光度计进行光谱扫描以选择乳酸环丙沙星的入射波长;用Extreme C18柱（5μm,25 cm×4.6 mm）为色谱柱,流动相为0.025 mol/L磷酸溶液（三乙胺调节pH至3）-乙腈（87:13）,流速为1.0 mL/min,检测波长为λmax=279 nm,进样量为50μL,采用峰面积外标标准曲线法计算含量。结果表明:乳酸环丙沙星的最大吸收波长为279 nm,峰宽较窄;乳酸环丙沙星检测质量浓度线性范围为1.25～40μg/mL（r=1）,平均回收率99.50%（相对标准偏差=1.67%,n=9）。本法操作简便,快速,结果准确可靠,重复性较好,可用于测定乳酸环丙沙星原位凝胶中乳酸环丙沙星的含量。

[Objective] The study aimed to select the best process of Chinese Angelica Polysaccharide(CAPS) with water extraction and the optimum operating times of removing protein with method of Savag's.[Method] The orthogonal design was used to extract of CAPS.The Savag's method was used to remove protein from polysaccharide and the polysaccharide contents were compared after the different removing times.The total polysaccharide contents were determined with method of phenol-sulfuric acid,the protein content determined by method of Coomassie brilliant blue,the uronic acid content with method of sulfate-carbazole.[Result] The optimum extracting process was that ratio of material to water was 1∶20,the extraction time was 30 minutes,extraction temperature was 100 ℃ and the optimum process of removing protein was 3 times(5∶1 ratio of chloroform:n-butanol).[Conclusion] The method was simple and easy to operate and was suitable for extracting and detecting of water-soluble polysaccharide.