高效液相色谱——示差检测法测定去氢表雄酮硫酸盐的含量

本文报道了用高效液相色谱－示差检测法（HPLC－RI）测定去氢表雄酮硫酸酯钠盐（DHA－S）及其制剂含量的方法。采用反相ODS C18色谱柱，乙腈－水（含0.8%磷酸和10μmol/L四丁基氯氧化铵）作流动相，研究了色谱条件，回收率、检测限量及线性范围。     

舒他西林的反相离子对高效液相色谱分析法

为有效分离分析舒他西林及其杂质在稳定性考察中的变化情况，利用ＯＤＳ柱和腈基柱分别建立了２种反相离子对高效液相色谱分析系统，前者流动相为甲醇—四丁基氢氧化胺／三乙胺水溶液（含０．４％三乙胺的０．０１８ｍｏｌ／Ｌ四丁基氢氧化胺水溶液，用磷酸调ｐＨ４．０）＝２８７２；后者为乙腈—四丁基氢氧化胺水溶液（０．００５ｍｏｌ／Ｌ四丁基氢氧化胺水溶液，用磷酸调ｐＨ３．５）＝１９９。ＯＤＳ反相离子对色谱系统适合于准确测定稳定性考察中舒他西林含量的变化情况，而腈基柱反相离子对色谱系统则更适用于对舒他西林稳定性考察中诸相关物质的变化情况进行跟踪分析。利用建立的２种色谱系统，对舒他西林溶液的稳定性进行了考察，并对其水解过程进行了讨论。     

麦滋林颗粒剂中薁磺酸钠的HPLC测定

建立了反相离子对HPLC法测定麦滋林颗粒中薁磺酸钠含量.采用C18色谱柱,以乙腈-0.025mol/L磷酸氢二钠缓冲液(含四丁基硫酸氢铵0.01mol/L,磷酸调至pH7.0)(40:60)为流动相,检测波长为293nm.薁磺酸钠在12.5～112.5μg/ml范围内线性关系良好,方法平均回收率为101.1%.     

HPLC法测定枸橼酸咖啡因注射液中枸橼酸的含量

目的 建立枸橼酸咖啡因注射液中枸橼酸含量的高效液相色谱(HPLC)测定方法.方法 采用HPLC法,用C18色谱柱(4.6×250 mm,5μmm),以0.018 mol·L-1磷酸二氢钾溶液(含0.010 mol·L-1四丁基硫酸氢铵和2.69×10-5 mol·L-1 EDTA,pH值为2.0)为流动相A;甲醇为流动...     

十二烷基键合固定相的制备及在青霉素降解研究中的应用

采用2，4-戊二酮与正十二烷基二甲基氯硅烷在咪唑的催化下制成活漏的中间体-硅醚烷基中间体，再与硅胶进行键合，用元素分析法测得该固定相中C的质量分数为9.68%。利用该固定相，在流动相为乙腈，0.02mol/L磷酸盐缓冲液（pH6.0)(30:70,含0.006mol/L氯化四丁基铵）的条件下成功地分离了青霉素G及其三种主要降解产物。     

HPLC测定注射用头孢哌酮钠他唑巴坦钠中的有关物质

目的 采用HPLC法测定注射用头孢哌酮钠他唑巴坦钠中的有关物质.方法 采用CAPCELL PAK MGⅡC18色谱柱(250 mm ×4.6 mm,5 μm),流动相为5 mmol·L-1氢氧化四丁基铵溶液-乙腈(67∶33,用磷酸调pH4.0),流速1.0 mL· min-1,柱温30 ℃,检测波长230 nm.结果 各杂质与头孢哌酮和他唑巴坦两色谱峰均能完全分离;精密度及耐用性均符合要求.结论 所用方法准确、灵敏、专属性强,可用于注射用头孢哌酮钠他唑巴坦钠中有关物质的检查.     

注射用头孢他啶-他唑巴坦钠含量测定方法研究

目的建立测定注射用头孢他啶-他唑巴坦钠含量的方法.方法采用HPLC法,色谱柱为ODS,流动相为乙腈-10%氢氧化四丁基铵(190∶10),并用磷酸调节pH为4.0,检测波长为230nm.结果精密度及稳定性均良好;头孢他啶及他唑巴坦浓度分别在100～900.9μg*mL-1和22.8～205.2μg*mL-1范围内,峰面积与浓度呈良好的线性关系,相关系数为0.9998和0.9997,平均回收率分别为99.9%和99.7%.结论本方法简便、专属、重现性好,可同时测定他唑巴坦钠和头孢他啶的含量.     

瑞巴派特的HPLC测定

采用ＨＰＬＣ测定瑞巴派特含量及其杂质。色谱柱为ＹＷＧＣ１８,流动相为甲醇－ＰＨ６．５磷酸盐缓冲液（含１％氢氧化四丁基铵的１０％水溶液（５２：４８）。方法简便、结果准确。     

高效液相色谱法测定氟哌酸和丙氟哌酸的血、尿浓度

氟哌酸和丙氟哌酸是新型的具广谱抗菌活性的喹诺酮类抗菌药物。作者用高效液相色谱法(HPLC)测定了白血病或骨髓移植病人体液中该二药的浓度,并和生物法作了比较。所采用的色谱条件为:μBondapak C18层析柱(10μm,15cm×3.9mm),流速2ml/min,荧光检测器检测,激发波长和发射波长分别为278和456nm;流动相由乙腈-四丁基铵氢氧化物-磷酸缓冲液(pH3.0)组成,缓冲液配制为1.67m185%磷酸,15mll.54M     

液相色谱结合液质联用法测定酮康唑原料药及复方酮康唑软膏中的有关物质

摘要：目的 建立一种复方酮康唑软膏中有关物质的液相色谱及液相色谱质谱测定方法。方法 采用Agilent HPLC,选择 ZORBAX Eclipse Plus C18色谱柱(250mm×4.6mm,5mm),以10mmol/L四丁基硫酸氢铵溶液-乙腈(85:15)为流动相A,10mmol/L 四丁基硫酸氢铵溶液-乙腈(20:80)为流动相B,流速为1mL/min,检测波长为220nm。经优化流动相比例确定了线性梯度洗脱, 开展了专属性、线性、准确度、精密度、重复性、稳定性和耐用性等方法学研究。并将该方法应用于酮康唑原料药及复方酮康 唑软膏中有关物质的检测。在液相色谱-四级杆飞行时间质谱方法中,选择0.1%甲酸水溶液为流动相A,乙腈为流动相B,梯度 洗脱,通过二级质谱数据推导了酮康唑的裂解规律。结果 通过检测酮康唑原料药、复方酮康唑软膏并结合降解实验结果发 现,酮康唑与相邻杂质均可实现基线分离。根据确定的HPLC方法对比了不同来源复方酮康唑软膏有关物质的差异。建立了基 于高分辨质谱的酮康唑及其杂质的结构解析方法,修正了酮康唑及杂质E的特征子离子的产生过程及结构,并确认了酮康唑的 主要降解杂质为杂质D。结论 本方法灵敏度较高、重复性较好,为复方酮康唑软膏的质量控制提供了一种可行的分析方法, 适用于该产品的质量控制。基于高分辨质谱的结构解析方法也为酮康唑中其他杂质的结构推断提供了研究基础。     

Determination of furosemide in rat plasma using HPLC and liquid scintillation

A rapid and convenient HPLC method for the determination of furosemide in plasma is described. The method uses a buffered mobile phase containing 22% (v/v) acetonitrile. The precision, detection limit and the correlation between the HPLC method and a liquid scintillation determination of furosemide are satisfactory. A pharmacokinetic study of furosemide in the rat is described.     

Dissociation constants and assay of weak bases in non-aqueous solvents

A method is described for evaluating standard cell potentials of specific electrode pair systems in anhydrous acetic acid and acetonitrile. The dissociation constants (K_HB+) in acetonitrile and the overall dissociation constants (K_B) and (K_BHCIO4) in anhydrous acetic acid of a series of bases of pharmaceutical interest have been determined. Simple potentiometric and visual titration methods are proposed for the assay of bases and their mixtures.     

Analysis of the angiotensin-converting enzyme inhibitors perindopril,lisinopril, and quinapril by HPLC

A unified HPLC method for analyzing the angiotensin-converting enzyme (ACE) inhibitors perindopril, lisinopril, and quinapril using a single column with a nonpolar phase based on octadecylsilica gel and a universal eluant (a mixture of acetonitrile and aqueous heptanesulfonic acid and triethylamine) is described; this method significantly decreases workload and the cost of analysis. The method can be used for the analysis of substances and different therapeutic formulations containing ACE inhibitors.     

Quantitative and qualitative HPLC analysis of thermogenic weight loss products

An HPLC qualitative and quantitative method of seven analytes (caffeine, ephedrine, forskolin, icariin, pseudoephedrine, synephrine, and yohimbine) in thermogenic weight loss preparations available on the market is described in this paper. After 45 min the seven analytes were separated and detected in the acetonitrile: water (80:20) extract. The method uses a Waters XTerra RP18 (5 microm particle size) column as the stationary phase, a gradient mobile phase of water (5.0 mM SDS) and acetonitrile, and a UV detection of 210 nm. The correlation coefficients for the calibration curves and the recovery rates ranged from 0.994 to 0.999 and from 97.45% to 101.05%, respectively. The qualitative and quantitative results are discussed.     

Reversed-phase high performance liquid chromatographic determination of carbaryl in postmortem specimens

A reversed-phase high performance liquid chromatographic (HPLC) method has been developed for the analysis of carbaryl in postmortem samples. It involves the use of an aqueous acetonitrile mobile phase to give rapid, reproducible analyses and an external standard for quantitation. Two separate extraction procedures (Extrelut column and protein precipitation with acetonitrile) are described; each one is suited to a particular substrate and each one leads to an almost complete recovery of carbaryl from that substrate.     

The use of 7,7,8,8-tetracyanoquinodimethane for the determination of nortriptyline and desipramine in tablets

A sensitive and selective spectrophotometric method is described for the assay of nortriptyline and desipramine. The method is based on the interaction of these drugs as electron donors with 7,7,8,8-tetracyanoquinodimethane (TCNQ) as a π-acceptor in acetonitrile at 80°C, to give highly coloured chromogens which exhibit maximum absorption at 567 nm. The proposed method was successfully applied to the determination of these drugs (as salts) in sugar-coated tablets.     

The determination of metoclopramide in plasma by reversed-phase ion-pair high-performance liquid chromatography

Methodology based on reversed-phase ion-pair high-performance liquid chromatography is described for the determination of metoclopramide in plasma. The chromatography was optimized in terms of the peak shape for the drug and its resolution from endogenous plasma components by investigating the effects of quaternary ammonium (competing) ions and alkylsulphate (pairing) ions in an acidic mobile phase containing acetonitrile (20%) and 20 mM acetic acid. Optimum chromatographic conditions were obtained with an ODS-Hypersil column and a mobile phase containing 20% acetonitrile, 20 mM acetic acid, 0.6 mM sodium octylsulphate and 0.5 mM tetrabutylammonium chloride. A simplified method of sample preparation is described in which only 1 ml of plasma is required. The limit of detection (at 310 nm) was 7 ng/ml and no interference from endogenous plasma components or from any drugs commonly used in the treatment of cancer was observed. Consequently the methodology should be applicable to pharmacokinetic studies on metoclopramide, when used clinically to control the gastro-intestinal side-effects of chemotherapy.     

HPLC-UV determination of metformin in human plasma for application in pharmacokinetics and bioequivalence studies

In this study, a simple, rapid and sensitive HPLC method with UV detection is described for determination of metformin in plasma samples from bioequivalence assays. Sample preparation was accomplished through protein precipitation with acetonitrile and chromatographic separation was performed on a reversed-phase phenyl column at 40 degrees C. Mobile phase consisted of a mixture of phosphate buffer and acetonitrile at flow rate of 1.0 ml/min. Wavelength was set at 236 nm. The method was applied to a bioequivalence study of two drug products containing metformin, and allowed determination of metformin at low concentrations with a higher throughput than previously described methods.     

高效液相色谱法测定环孢素 A 血药浓度

采用高效液相色谱法测定环孢素 A(CsA)的血药浓度。色谱条件:国产 YWG-C_(18)柱,流动相为乙腈:水(80:20,V/V),流速1.0ml/min,柱温60℃,紫外检测波长214nm,内标法定量。结果显示,简化的血样抽提方法回收率较高,平均76.3±1.7%,最低检测限达20μg/L。此法应用于肾移植病人的血药浓度监测,发现我国人群 CsA 的有效血药浓度范围较大。     

Analysis of steroids. Part 45: Analytical investigation of pipecuronium bromide (Arduan)]

The following methods are described for the analytical investigation of pipecuronium bromide. 1. HPLC method. Of the several systems tried for the separation and quantification of impurities and degradation products the best results were obtained using silica as the stationary phase and 43:43:14 mixture of methanol, acetonitrile and concentrated aqueous ammonia containing 0.1 mole/l each of ammonium chloride and ammonium carbonate as the eluent. The validation of this method is presented. The above described aggressive eluent can be successfully replaced by an ion-pairing system using silica as the stationary phase and 96:4 mixture of acetonitrile and water containing 0.1 mole/l sodium perchlorate as the eluent. 2. Thin-layer chromatography. TLC systems are described for the separation and densitometric quantification of the impurities and degradation products of pipecuronium bromide. 3. Spectrophotometry. Two methods are described. The ester groups of the molecule can be determined by the iron(III)-hydroxamate method while for the ion-pair extraction of the quaternary ammonium steroid picric acid or bromthymol blue are used as the reagents. 4. Titrimetry. In addition to the titration with acetous perchloric acid for the assay of the bulk material a microtitration method is described for the determination of pipecuronium bromide in individual lyophylized ampoules (potentiometric titration with 0.1 M silver nitrate).