醋酸羟丙基甲基纤维素琥珀酸酯的性能表征

 目的合成新型肠溶包衣材料醋酸羟丙基甲基纤维素琥珀酸酯(HPMCAS),并分析其结构特征和性能。方法采用红外光谱、紫外光谱、热重分析和化学分析等方法进行表征,测试HPMCAS在有机溶剂中的溶解情况、黏度、抗张强度和极限伸长率,并与日本的醋酸羟丙基甲基纤维素琥珀酸酯样品AS-LG进行比较。结果HPMCAS中酸性丁二酰基、乙酰基的含量与加入酸酐的量密切相关;二氯甲烷-乙醇等混合溶剂是HPMCAS的良溶剂;HPMCAS低于200℃时对热稳定,高于此温度后快速失重。结论其物化性质与日本样品AS-LG接近。     

醋酸地塞米松片补充检验方法的研究

对现行版<中国药典>"醋酸地塞米松片"质量标准提出改进意见,建立高效液相色谱法测定醋酸地塞米松片中的醋酸地塞米松含量.色谱柱:Diamonsil(TM)钻石C18(4.6mm×200mm,5μm);流动相:甲醇-水(70:30);检测波长:240nm;流速:1.0ml·min-1.醋酸地塞米松的线性范围为11.16～39.06μg·ml-1,r=0.9999,平均回收率为98.82%,RSD为1.76%.本方法简单,专属性强,重现性好,易于操作.     

雷公藤提取物固体脂质纳米粒水分散体的制备及体外透皮吸收

制备雷公藤乙酸乙酯提取物固体脂质纳米粒水分散体,并初步研究了体外透皮行为.     

乙酸对氰基苯酯的制备改进

苯并吡喃类钾通道启开剂是近年研发的新型抗高血压药物,乙酸对氰基苯酯(1)是合成此类化合物的重要中间体[1].文献[2]以对氰基苯酚(2)在NaOH溶液中与乙酸酐(3)反应2h后,依次用Na2CO3溶液和水洗涤制得,收率90%.     

醋酸地塞米松静注乳剂的含量测定

目的:建立醋酸地塞米松静注乳剂的含量测定方法.方法:采用C18色谱柱(4.60cm×25cm,10μm),流动相为水(含0.164mol/L磷酸,用三乙胺调pH值至3.5)-乙腈(43:57),以甲磺酸酚妥拉明为内标.结果:醋酸地塞米松量在1.84μg/mL～46.0μg/mL时,与峰面积比值呈良好线性,回归方程为A e=0.0868C 0.00885(r=0.9999,n=6),方法的日内与日间精密度RSD均小于2%,回收率分别为100.1%,98.7%和99.8%.结论:该方法快速准确、精密,可以用于该制剂的含量测定及稳定性分析.     

RP-HPLC鉴别三七粉中的醋酸地塞米松

 目的 检测三七粉中掺入的醋酸地塞米松。方法 采用反相高效液相色谱法,C₁₈柱,流动相为甲醇-水梯度洗脱或乙腈-四氢呋喃-水(25:18:57)等度洗脱，检测波长240 nm。结果 在两种液相条件下，供试品溶液中均检出醋酸地塞米松，且样品中的醋酸地塞米松与其他杂质峰能有效分离，通过比较供试品和对照品色谱保留时间和其紫外光谱信息，以及样品中峰纯度检查，供试品中含有醋酸地塞米松。结论 本测定方法简便、灵敏、专属性强。     

HPLC法测定复方醋酸氯己定洗剂中醋酸氯己定和克霉唑含量

目的:建立复方醋酸氯己定洗剂的含量测定方法.方法:采用高效液相色谱法,μBndapak-C18柱(5μm,250 mm×3.9 mm);流动相为乙腈-甲醇-水(21:37:42),每1000ml内含磷酸5ml,三氟乙酸1 ml,三乙胺调pH3.9～4.0;流速为1 ml·min-1;检测波长为230 nm.结果:醋酸氯己定和克霉唑分别在10～125μg·m1和2～25 μg·ml-1范围内线性关系良好;平均回收率分别为95.6%及96.5%(RSD 1.2%,1.5%).结论:本法色谱分离效率高,专属性好,同时测定两种成份,方法简便.     

Total esterase activity in human saliva: Validation of an automated assay,characterization and behaviour after physical stress

Although saliva has esterase activity, this activity has not been characterized or studied in individuals subjected to physical stress. The aim of this report was to develop and validate an automated spectrophotometric assay for total esterase activity measurement in human saliva, as well as to study the contribution of different enzymes on this activity and its behaviour under physical stress in healthy subjects. The assay used 4-nitrophenyl acetate as substrate and was precise, accurate and provided low limits of detection and quantification. Inhibition with diisopropylfluorophosphate showed that cholinesterase, carboxylesterase and cholesterol esterase contributions not represented more than 20% of total esterase. Addition of standards of lipase and albumin to saliva samples showed that both proteins significantly contributed to esterase activity only when equal or higher than 11.6?IU/L and 250?μg/mL, respectively. Western blot analyses showed absence of paraoxonase-1 and high amount of carbonic anhydrase-VI. The high affinity of purified carbonic anhydrase-VI for the substrate supported a major contribution of this enzyme. Total esterase activity and alpha-amylase was measured in saliva samples from 12 healthy male students before and after participation in an indoor football match. The activity significantly increased after match and positively correlated with salivary alpha-amylase. This method could be used as a biomarker of physical stress in humans, with carbonic anhydrase-VI being the esterase that contributed more to the activity of the assay.     

Good results for early treatment of clinically isolated syndrome prior to multiple sclerosis with interferon beta-1b and glatiramer group

The first sign of developing multiple sclerosis is a clinically isolated syndrome that resembles a multiple sclerosis relapse. Objective/methods: The objective was to review the clinical trials of two medicines in clinically isolated syndromes (interferon β and glatiramer acetate) to determine whether they prevent progression to definite multiple sclerosis. In the BENEFIT trial, after 2 years, 45% of subjects in the placebo group developed clinically definite multiple sclerosis; the rate was lower in the interferon β-1b group. All subjects were then offered interferon β-1b, and the original interferon β-1b group became the early-treatment group and the placebo group became the delayed-treatment group. After 5 years, the number of subjects with clinical definite multiple sclerosis remained lower in the early-treatment than in the late-treatment group. In the PreCISe trial, after 2 years, the time for 25% of the subjects to convert to definite multiple sclerosis was prolonged in the glatiramer group. Interferon β-1b and glatiramer acetate slow the progression of clinically isolated syndromes to definite multiple sclerosis. However, it is not known whether this early treatment slows the progression to the physical disabilities experienced in multiple sclerosis.