Validated Flow Injection Spectrophotometric Assay for the Quality and Stability Control of Gemfibrozil Tablets

Abstract

A validated flow injection spectrophotometric assay has been developed and optimized for the determination of gemfibrozil in pharmaceutical formulations. The method is based on the direct measurement of the absorbance of the analyte—under flow conditions—in basic medium, at 276 nm. The assay was optimized in terms of sample injection volume and flow rate and validated in terms of linearity, repeatability, detection limit, accuracy, and selectivity. Linear calibration curve was obtained in the range of 20–100 mg l^?1, while the detection limit (1.4 mg l^?1), the repeatability (s _r <1.0%, n=12) and the sampling rate (30 h^?1) were satisfactory. The method was applied successfully to the quality control of one batch (batch no. 052) and the stability control of three batches (batches no. 049–051) of a gemfibrozil‐containing formulation (Prelisin^®, Cosmopharm Ltd, Greece).     

氯霉素片中氯霉素含量的HPLC法测定

采用高效液相色谱法测定氯霉素片中氯霉素的含量，用C18柱为分离柱，水-甲醇-冰醋酸（体积比55：45：0.1）为流动相，检测波长278nm，氯霉素进样量在1.6-2.4μg范围内与主峰面积线性关系良好（r=0.9996），平均回收率为101％，重复进样相对标准偏差0.40％（n=7）。     

色谱指纹图谱在香精香料质量控制中的应用

烟用香精香料化学成分复杂,现无合适的化学质量控制方法,通过实例,对10个批次正常生产的香料标样进行同时蒸馏萃取,取其萃取液进行气相色谱氢焰检测.进行同组分色谱峰的匹配,根据相对峰面积求出标准指纹图谱,然后10批标样各自与标准指纹图谱进行相似度计算,据此设立待测样品的合格性允差范围.待测样品与标准指纹图谱进行谱峰匹配,计算与标准指纹图谱的相似度,依据合格性允差范围,判定其质量状况.     

纳米金-二氧化钛纳米针修饰电极用于氯霉素检测

将金胶-TiO2纳米针修饰玻碳(Au-TiO2/GC)电极用于对氯霉素(CAP)浓度的电化学测定。 结果表明,在0.1 mol/L pH=7.0的磷酸盐缓冲溶液(PBS)体系中,CAP在Au-TiO2/GC电极上有较好的电化学响应,CAP浓度在8.0×10-7～1.0×10-4 mol/L范围内,峰电流与其浓度呈良好的线性关系,检出限为7.8×10-8 mol/L。 并对氯霉素滴眼液中CAP浓度进行了检测,发现该方法有高的检测灵敏度、好的重复性和抗干扰性,且操作简便、成本低廉。     

氯霉素分子印迹聚合膜电极的制备及氯霉素检测

以邻氨基酚(OAP)为功能单体,氯霉素(CAP)为模板分子,用电化学聚合的方法在Pt上合成了CAP分子印迹（MIP）OAP膜(CAP-MIP-OAP/Pt)电极,通过扫描电子显微镜和电化学技术对聚合膜的结构和性能进行了表征。 结果表明,该膜电极对CAP检测有较好的选择性和灵敏度,CAP检测的线性范围为4.33×10-8～3.09×10-6 mol/L,检出限为2.5×10-8 mol/L。     

Analyses of Chloramphenicol in Biological Samples by HPLC

Abstract

Chloramphenicol (CAP) is the drug of choice for the treatment of typhoid fever and other diseases and is consumed by millions of people. Chloramphenicol is a broad-spectrum antibiotic, but it has serious side effects and high risk of anemia if taken continuously. The drug persists for a long time in the human body and is likely to damage to the liver, kidneys, and red blood cells, even at low concentrations. From the human health point of view, analysis of low levels of this drug in biological samples is important. This article present an overview of the analysis of CAP in biological samples by high-performance liquid chromatography (HPLC). In addition, the available methods are compared in terms of their applications, efficiencies, and effectiveness.     

Excel VBA在化学分析质量控制中的应用

采用Excel VBA开发了化学分析质量控制图系统。用VBA语言编制出质控图生成、判定程序,再利用Excel内置图表功能将所有的质控图像显示在操作界面。该系统可对录入的原始数据进行审查并自动生成质量控制图表,在日常的质控活动时可以自动判定所分析的质控样结果是否满足质量控制要求。该系统的判定结果与理论统计结果一致。     

正二十二烷醇的热力学性质

用精密自动绝热量热仪测定了广谱抗病毒药物正二十二烷醇在78-400 K温区的热容. 根据实验测定的热容数据, 用最小二乘法拟合计算出热容对温度的多项式方程, 得到其相变温度、相变焓、相变熵分别为340.844 K、85.07 kJ·mol-1、249.6 J·K-1·mol-1. 根据热力学函数关系式计算了其在80-400 K温区每隔5 K的热力学函数[HT-H298.15]和[ST-298.15]. 用DSC、TG热分析技术进一步考查了该物质在400-900 K的热稳定性.     

生物降解材料胆酸-乳酸共聚物的热性能研究

通过直接熔融共聚法合成了系列的不同乳酸／胆酸组成比（LA／CA）的胆酸．乳酸共聚物,用DSC、TG等手段研究生物降解材料胆酸-乳酸共聚物的热性能。结果表明,共聚物的热性能与其组成、结构有关。LA／CA小的多核共聚物无明显熔融峰,热失重分两步进行;LA／CA大的单核共聚物出现明显双头熔融峰,其热失重一步进行,其Tg随着LA／CA增加而升高。     

高效毛细管电泳拆分氯霉素前体

采用未涂层毛细管柱 (5 5cm× 5 0 μm) ,基于H3 BO3 与 β CD络合成大阴离子作为手性拆分试剂 ,在NaOH Cit溶液中加入 9 0mol/LH3 BO3 与 7 0mmol/L β CD(pH =3 0 )作为运行缓冲液 ,用高效毛细管电泳电导检测法对氯霉素前体 (PCP)进行了拆分研究。考察了影响分离的实验参数 ,同时对其拆分机理进行了初步探讨。结果表明 ,在选择的最佳实验条件下 ,氯霉素前体分子中 4个对映异构体在 2 0min内得到基线分离 ,所建立的方法分离条件简单 ,重现性好。     

热分析技术在药物研究中的应用

本文简要介绍了热分析技术在药学领域中的重要性及其应用。由于热分析技术具有试样微量化、快速简便、不用分离试样、不用溶剂、适用范围广、曲线易于解析等优点,在药学研究和药品质量检验等方面,热分析技术将发挥更重要的作用。     

Thermal analysis of the rice and by-products

The thermogravimetry (TG) is a technique used in the quality control of foods. In this work the moisture and ash contents in the rice and by-products (bran and husk), the thermal stability and the gelatinization process by conventional, thermogravimetric and calorimetric methods were studied. The moisture and ash contents obtained by TG and conventional methods did not present significant differences. The rice presented higher starch content, while the bran presented higher protein content. The thermogravimetric data presented the following thermal stability order: rice>bran>husk. The calorimetric curves indicated the gelatinization of the starch. The kinetic parameters were compatible. This revised version was published online in August 2006 with corrections to the Cover Date.     

指纹图谱法在参麦注射液质控中的应用

 中医药理论和实践要求综合评价中药的质量 ,指纹图谱法是对中药制剂进行综合宏观分析的可行手段之一 ,因此采用反相高效液相建立了参麦注射液的特征指纹图谱。条件 :Hypersil C18(4 6mmi d × 2 5 0mm ,5 μm)反相柱 ,流动相由水 (A)和乙腈 (B)组成 ,B的体积分数在 5 0min内由 5 %线性增长到 95 % ,流速为1 0mL/min ;紫外检测 ,波长为 2 0 2nm。 2 3个特征指纹峰与内标 (联苯 )的峰面积比作为指标 ,结合主成分分析 投影判别法比较了同一厂家不同批次产品和不同厂家同类产品的化学指纹差异。     

Application of thermomagnetometry to corrosion studies of archaeological iron

Summary Thermomagnetometry has been applied to mineralized archaeological iron samples and samples from accelerated corrosion tests. It has successfully quantified the degree of corrosion, measured by the loss of iron, as well as the amount of magnetite formed and water held in the corrosion and adhered soil layers. Thermomagnetometry, thermogravimetric analysis and differential scanning calorimetry have been applied to the reported corrosion products from archaeological iron. Fourier transform infra-red and Raman spectroscopies and X-ray diffraction analyses were undertaken on the residues and at intermediate heating stages, where the thermal analyses indicated, to identify the reaction products.     

聚缩水甘油硝酸酯的热安定性和相容性研究

采用DSC、TG热分析方法研究了聚缩水甘油硝酸酯(PolyGLYN)的热安定性和与1,3,5-三硝基-1,3,5-三氮杂环己烷(RDX)间的相容性.结果表明,PolyGLYN在100℃以前较为稳定.当加热速率趋于零时PolyGLYN的热分解峰温为196.4℃,由Ozawa法计算的热分解表观活化能为182.0 kJ·mol-1,分别比RDX的低15.1℃和高22.2 kJ·mol-1.PolyGLYN热稳定性与RDX接近,两者之间的相容性较好.     

HPLC法测定氯霉素氢化可的松滴耳液中两组分的含量

采用反相高效液相色谱法,以醋酸泼尼松为内标,ＵＶ检测波长为２４４ｎｍ,以ＹＷＧ－Ｃ１８为固定相,以甲醇－水（６０∶４０）为流动相,同时测定了氯霉素氢化可的松滴耳液中氯霉素和氢化可的松的含量,并进行了线性范围和回收率测定,平均回收率（ｎ＝６）和相对标准偏差分别为：９９．９１％和０．８６％（氯霉素）,９９．５８％和１．３４％（氢化可的松）。     

对虾中氯霉素残留的分析方法研究

用液相色谱-质谱法定量检测对虾中微量的氯霉素残留。采用乙酸乙酯超声提取对虾组织中的氯霉素残留,以甲醇为流动相,选择m／x321／152为氯霉素的检测离子对,用多反应监测(MRM)技术测定。氯霉素流出液相色谱的时间在1．5min以内;线性范围是0．28-28．0μg／L;线性相关系数为0．99991。对虾中氯霉素的定量检测下限是0．07μg／kg,平均回收率在89％以上。该方法快速、灵敏,定量范围宽,检验结果准确可靠,应用性强。     

数理统计在地球化学样品分析质量控制中的应用

使用Excel2013和Minitab两种常用软件对地球化学样品中CaO含量分布情况进行了研究,运用描述性统计、正态分布、背景值与异常方法对实验室分析的广西某地地球化学样品的分析数据进行了质量评价,结果表明:综合运用计算机软件和数理统计方法,能快速找到分析数据的详细信息和数据特征,判别地球化学样品实验室分析数据的准确性,找出元素的背景值和异常值并剔除异常值,比较发现,样品中CaO含量分析数据对数转换后比原始数据的分布更趋于正态分布,相比于X射线荧光光谱方法,用电感耦合等离子体发射光谱法测定的结果更符合正态分布。方法对地球化学调查样品的分析数据质量评价作了有益的尝试,揭示了数理统计方法是地球化学样品分析质量控制的有效手段。     

基于离子液体辅助氯霉素分子印迹聚合物的制备及应用

以氯霉素(CAP)为模板,2-乙烯基吡啶(2-Vp)为功能单体,四氢呋喃和离子液体1-丁基-3-甲基咪唑四氟硼酸盐[BMIm]BF4的混合溶液为反应溶剂,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,合成了氯霉素的分子印迹及非印迹聚合物。优化功能单体、不同溶剂对印迹聚合物吸附性能的影响,结果表明,以2-乙烯基吡啶为功能单体,四氢呋喃和离子液体[BMIm]BF4(体积比1∶1)作为反应溶剂合成的分子印迹聚合物对氯霉素具有高的吸附容量,良好的特异性识别性能。氯霉素分子印迹聚合物的印迹因子为2.6,进行吸附-解吸附循环5次后,氯霉素印迹聚合物的性能稳定,可重复使用。将制备的氯霉素分子印迹聚合物作为富集材料,应用于鸡蛋样品中氯霉素的检测,回收率可达62.3%~81.1%,准确性好。     

Thermal Decomposition Characteristics of 1,7-Diazido-2,4,6-trinitrazaheptane and its Application in Propellants

The thermal decomposition characteristics of1,7-diazido-2,4,6-trinitrazaheptane (DATH) and multi-component systems containing DATH were studied by using DSC, TG and DTG techniques. Three –NO₂ groups in the DATH molecule break away first from the main chain when DATH is heated up to 200°C. Following this process, the azido groups and the residual molecule decompose rapidly to release a great deal of heat within a short time. In the multi-component systems, DATH undergoes a strong interaction with the binder of the double-base propellant and a weak interaction with RDX. The burning rates of the two propellants were determined by using a Crawford bomb. The results showed that the burning rate rises by about 19–66% when 23.5%DATH is substituted for RDX in a minimum smoke propellant. Meanwhile, the N₂ level in the combustion gases is enhanced, which is valuable for a reduction of the signal level of the solid propellant. This revised version was published online in July 2006 with corrections to the Cover Date.