Tb3+敏化化学发光法测定氟罗沙星

利用Tb3+能大大增强Ce*$-H2SO3-FLX的化学发光,建立了一种简单、快速、高灵敏度、高选择性的测定氟罗沙星的新方法,氟罗沙星浓度在2.0×10-9～8.0×10-8 mol/L范围内时,发光强度与氟罗沙星浓度呈良好的线性关系,方法的检出限为8.3×10-10 mol/L,对2.0×10-8 mol/L的氟罗沙星平行测定11次,相对标准偏差为1.2%.并用该方法测定了沃尔得及天方片剂中氟罗沙星的含量,不经任何预处理,直接测定了尿样中氟罗沙星的含量及回收率,结果令人满意.     

线性扫描伏安法测定氟罗沙星

应用线性扫描伏安法和循环伏安法研究氟罗沙星在玻碳电极上的电化学行为。在含有铜离子的pH 6.5的0.10mol.L-1磷酸盐缓冲溶液中,铜离子在玻碳电极上分别于-0.136V和-0.728V处形成两个还原峰,加入氟罗沙星后铜离子的还原峰电位不变但峰电流均降低。在优化的试验条件下,于-0.136V处的峰电流降低值Δip与氟罗沙星浓度在6.40×10-7～1.5×10-4 mol.L-1范围内呈线性关系,检出限为2.10×10-7 mol.L-1。方法用于氟罗沙星片剂中氟罗沙星含量的测定,回收率在96.8%～103.5%之间。     

痕量氟罗沙星和司帕沙星的荧光薄层色谱法测定

建立了硅胶G板上分离氟罗沙星(FLX)和司帕沙星(SPLX)并同时测定其在体液中含量的方法 ;用0.27mol·L -1、pH=7的EDTA溶液修饰硅胶G板 ,避免了试样与金属离子的络合作用 ;使用乙醇 -乙酸乙酯 -1,2_二氯乙烷 -10 %(φ)氨水(体积比4∶3∶2∶1)为展开剂 ,FLX和SPLX的Rf值分别为0.40和0.59 ;板上的荧光斑点 ,使用CS_9000双波长薄层色谱扫描仪以285nm为激发波长扫描 ,同板标准工作曲线法定量 ;线性范围分别为0.5～85ng(FLX)和0.5～100ng(SPLX) ,回收率为96 %～102 % ,相对标准偏差≤5.2 % ;该法用于血样与尿样测定 ,具有操作简单 ,灵敏、准确的特点     

吸附转移溶出伏安法测定氟罗沙星注射液含量

氟罗沙星 (ｆｌｅｒｏｘａｃｉｎ ,ＦＬＲＸ)是一种抗菌谱广 ,杀菌力强的三氟喹诺酮类抗菌药[1] 。ＦＬＲＸ含量的测定方式主要有ＨＰＬＣ法[2 ,3] 、紫外分光光度法[3,4 ] 和荧光分光光度法[5] 。本文研究ＦＬＲＸ在不同支持电解质中的电化学行为 ,发现其在石墨电极表面有很强的吸附性 ,在一定的电位下富集几分钟 ,电极冲洗后在底液中扫描 ,仍有很大的峰电流。在此基础上建立了吸附转移溶出伏安法(ＡｄＴＳＶ) [6 ] 测定ＦＬＲＸ。方法的线性范围为 4～42 μｇ/ｍｌ,用于ＦＬＲＸ葡萄糖注射液中ＦＬＲＸ含量的测定 ,比其他方法灵敏、准确、…     

司帕沙星含量的HPLC测定

司帕沙星是一类喹诺柄类抗菌药物,该文采用反相高效液相色谱法对其生产进行质控分析,测定中选用Ｃ１８柱,以甲醇－水（内含４０ｍｍｏｌ．Ｌ＾－１的磷酸二氢钾和３０ｍｍｏｌ．Ｌ＾－１的四乙基溴化铵,Ｖ甲醇：Ｖ水＝４５：５５）为流动相,于２９８ｎｍ进行检测,样品测定的回收率为９７．９％～１００．２％,相对标准偏差不大于２％。     

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）。     

氟罗沙星的电化学特性研究

本文报道测定氟罗沙星(FLRX)的新方法。在0.05 mol/L KH2PO4 NaOH(pH=7.12)缓冲溶液中,FLRX Cu(Ⅱ)络合物在-0.36 V(vs.SCE)处产生一个灵敏的不可逆吸附还原峰。峰电流ip 与氟罗沙星浓度在5.0×10-8~4.0×10-6 mol/L范围内呈良好的线性关系,检测下限可达3.0×10-8 mol/L。络合物性质和电极反应机理研究表明,络合物组成比为:Cu(Ⅱ)∶FLRX=1∶2,是以Cu(Ⅱ)为中心原子,四个O为配位原子的螯合物。其电极过程为具有吸附性的不可逆还原过程。     

共振瑞利光散射法测定人体尿液和血浆中的氟罗沙星

提出了共振瑞利光散射法测定氟罗沙星的新方法。在pH5.3～5.6的Britton-Robinson缓冲溶液中,氟罗沙星(FLE)与钴(II)能形成螯合阳离子,它可进一步与刚果红(CR)反应形成2∶1∶1(FLE∶Co2+∶CR)三元离子缔合物,导致共振瑞利散射(RRS)显著增强并出现新的RRS光谱,其最大散射波长分别位于372和560nm。在372nm处,氟罗沙星的浓度在0.03～3.69μg/mL范围内,与RRS强度有良好的线性关系,检出限(3σ)为6.0ng/mL。方法用于片剂、尿液和人血清中氟罗沙星的测定。     

HPLC法测定西沙必利片的含量

建立了测定西沙必利片含量的HPLC法。以Kromasil Cl8柱为色谱柱、0．02mol／L磷酸二氢钾缓冲液(pH=4．5)-乙腈(体积比为70：30)为流动相，流动相的流速为0．8mL／min，检测波长为308nm。西沙必利的浓度在5-125μg／mL范围内与色谱峰面积呈线性关系，线性相关系数r=0．9998，测定结果的平均加标回收率为99．91％，相对标准偏差为0．33％。     

测定诺氟沙星胶囊含量的HPLC法

用高效液相色谱法测定了诺氟沙星胶囊的含量。采用岛津ShimpackODS色谱柱;0.1%(φ)磷酸溶液-甲醇 (体积比55∶25,含1%(φ)三乙胺 ,磷酸调pH2.7)为流动相;检测波长278nm;外标法定量 ,样品测定结果与药典的方法一致。该法快速、准确、可靠 ,结果满意。     

用高效液相色谱法快速测定头孢氨苄胶囊中头孢氨苄含量

采用反相HPLC法 ,在C18 柱上以甲醇 -磷酸盐缓冲液 (pH7.4)为流动相 ,检测波长为254nm,快速测定头孢氨苄胶囊中头孢氨苄含量。方法简便、快速、准确;其平均回收率和相对标准偏差分别为100.2 %和0.79 %,测定样品结果与药典中的标准方法一致。     

Determination of Fleroxacin in Plasma by Direct Injection High Performance Liquid Chromatography with Column Switching

ABSTRACT

A high-performance liquid chromatography (HPLC) assay was developed for the determination of fleroxacin in plasma. The plasma samples were directly introduced onto a HPLC column after filtering through a MolcutII® membrane filter, which removes high molecular weight proteins. The fleroxacin in filtrate was separated from interfering substances and retained on a pre-column using an ODS stationary phase and then was introduced to an analytical column with an ODS stationary phase by column switching. Fleroxacin and lomefloxacin, as an internal standard, were detected by ultraviolet absorbance at 295 nm. Determination of fleroxacin was possible over the concentration range 50-4000 ng/ml; the limit of detection was 20 ng/ml. The recovery of fleroxacin added to plasma was 97.3-100.4% with a coefficient of variation of less than 2.2%. This method is applicable to drug level monitoring in the plasma of patients being treated with fleroxacin and of healthy volunteers participating in pharmacokinetic studies.     

高效液相色谱法测定冠心丹参胶丸中丹参素的含量

冠心丹参胶丸是一种复方中药软胶囊的新品种。为消除复杂的中药成分及多种药用辅料对定量测定的影响，研究建立了反相高效液相色谱法测定其中有效成分丹参素含量的方法，以０５％醋酸水溶液作流动相，在ＵＶ２８０ｎｍ波长处测定，操作快速简便、专属性强、重现性好，可作为控制产品质量的可靠的定量分析手段。     

Quantitative Analysis of Meclizine in Tablet Formulations by HPLC

Abstract

A simple, rapid and precise high-performance liquid chromatographic assay of meclizine in tablets has been developed. Reversed-phase chromatography was conducted using a mobile phase of acetonitrile and water (30% V/V) and detection at 230 nm. The recovery and coefficient of variation from six placebo tablets containing 25 mg of meclizine were 100.5% and 0.84%, respectively. Replicate regression analyses of three standard plots in the concentration range of 1–12 mcg/ml obtained on three different days gave a correlation coefficient >0.998 and the coefficient of variation of the slopes <1%. The assay was precise within day and between days as indicated by ANOVA test. The recoveries from 10 replicate tablets of the two different commercial meclizine brands were 98.5 and 100.7% of the label amount and their coefficients of variation were 1.16 and 1.71%.     

Simultaneous Determination of Cephalexin and Carbocisteine from Capsules by Reverse Phase High Performance Liquid Chromatography (RP - HPLC).

Abstract

A new, simple, precise, accurate and rapid RP- HPLC method has been developed for the simultaneous determination of Cephalexin and Carbocisteine from capsules, using 0.025 M monobasic sodium phosphate: acetonitrile (87:13, v/v) as a mobile phase, and a C₈ Shodex column as the stationary phase. Detection was carried out using a UV detector at 210 nm. The linearity range for Cephalexin and Carbocisteine were 50 - 300 μg/mL and 40 - 200 μg/mL, respectively. Assay values for Cephalexin and Carbocisteine were 99.46% (R.S.D. - 1.30%) and 99.22% (R.S.D.-1.34%) for Brand 1. and 99.71% (R.S.D. - 1.68%) and 99.43% (R.S.D. - 1.78%) for Brand 2, respectively.     

A Simple High-performance Liquid Chromatographic Assay for Loracarbef in Human Plasma

Abstract

A simple, rapid and reproducible high-performance liquid chromatographic (HPLC) method for the determination of loracarbef in human plasma has been developed and evaluated. Plasma protein was precipitated with ammonium sulfate. The drug and the internal standard (Cefetamet) were eluted from a μ-bondapak C-18 column with a mobile phase consisting of acetonitrile:methanol:water:glacial acetic acid (2.5:17.5:79.2:0.8%, v/v). The column eluent was monitored at 265 nm. Quantification was achieved by the measurement of the peak-height ratio of the analyte to the internal standard and the limit of quantification for loracarbef in plasma is 0.5 ug/ml. The within-day coefficient of variation (CV) ranged from 2.28% to 3.67%, and between-day CV from 2.38% to 5.59% at three different concentrations. The absolute recoveries ranged from 91.1% to 93.88%, and the relative recoveries from 93.4% to 108% at three different concentrations. Preliminary stability tests showed that loracarbef is stable for at least 5-weeks in human plasma after freezing. The method is applied for the determination of the pharmacokinetic parameters of loracarbef after oral administration to 2 beagle dogs.     

胶束薄层荧光法同时测定体液中诺氟沙星和氟罗沙星含量的研究

研究了胶束薄层色谱法测定体液中诺氟沙星(norfloxacin)和氟罗沙星(fleroxacin)含量的方法 ;以聚酰胺层析板为固定相 ,使用0.01mol/L的十二烷基磺酸钠(SDS)水溶液作为展开剂 ,并将EDTA溶液加入到展开剂中避免了氟哌酸 -金属离子络合物的生成 ,改善了分离条件 ;在此条件下 ,分离后的NFLX和FLX其Rf值分别为0.62和0.80 ;试样斑点经薄层色谱扫描仪用荧光法扫描定量 ,激发波长为278nm(NFLX)和285nm(FLX) ;两个化合物的线性范围分别是0～90ng/斑点 (NFLX)和0～80ng/斑点 (FLX) ;回归方程为c=4.96×10-3 A -2.94(NFLX)和c=2.98×10-3 A-3.54(FLX) ,相关系数均在0.998以上 ;在血样和尿样中回收率为98%～102% ,RSD<5.2%。     

High-Performance Liquid Chromatographic Assay for Chlorquine and its Two Major Metabolites,Desethylchloroquine and Bidesethylchloroquine in Biological Fluids

Abstract

A high-performance liquid chromatography (HPLC) method for the determination of chloroquine and its two major metabolites in biological fluids is described. Hydroxychloroquine is used as an internal standard (I.S.). Drug, metabolites and I.S. were extracted as bases with diethyl ether by a single step procedure. After drying and evaporation of the organic phase, the residue was dissolved into the mobile phase and injected into the chromatographic system. Separation was performed using a normal phase column (Inertsil sill with mixture of acetonitrile, methanol and ammonia as mobile phase. The detection was carried out by fluorescence measurement : excitation wavelength was set at 325 nm and emission at 380 nm. The limit of detection was near 3.7 ng ml^?1 for chloroquine and metabolites. No chromatographic interference could be detected by endogenous compounds or other antimalarial drugs. Because of the good accuracy of the method, concentrations were determinated with a relative standard deviation lower than 7% at the 25 ng ml^?l level for all substances.

An excellent precision was obtained over the range of concentrations tested, 25–1000ng ml^?l. This method can be applied to therapeutic, pharmacokinetic and epidemial studies.