HPLC法同时测定阿司匹林咀嚼片中阿司匹林和水杨酸的含量

目的用高效液相色谱法同时测定阿司匹林咀嚼片中阿司匹林和水杨酸的含量。方法采用Diamonsil C18色谱柱;以甲醇．醋酸．水（45：1：54）为流动相;流速：1．0mL·min-1,检测波长为275nm。结果阿司匹林线性范围：0．54～10．85μg（r=O．9999）,平均回收率为100．9％．RSD为O．36％（n=5）;水杨酸线性范围：2．65-31．77μg·mL-1（r=1．0000）,平均回收率为102．3％,RSD为2．O％（n=5）。结论此方法简便、快速、准确。值得推广应用。     

Simultaneous determination of codeine and ibuprofen in plasma by high-performance liquid chromatography

A procedure is described for the simultaneous determination of codeine and ibuprofen in human plasma following the administration of the two substances in a proposed combination dosage form. The two substances were extracted separately from plasma and then determined together by high-performance liquid chromatography (HPLC) using a fluorescence detector. The codeine was first extracted from alkalinized plasma with hexane-dichloromethane (2:1, v/v) and then washed with sodium hydroxide solution. The ibuprofen was then extracted with hexane from the plasma acidified with sulphuric acid. The organic layers were collected, evaporated to dryness and the reconstituted residue was subjected to HPLC. The detection limit for codeine was 8 microg 1(-1) and for ibuprofen 1 mg 1(-1).     

Simultaneous determination of atenolol and amlodipine in tablets by high-performance thin-layer chromatography

A new simple, precise, rapid and selective high-performance thin-layer chromatographic (HPTLC) method has been developed for the simultaneous determination of atenolol (ATL) and amlodipine (AMLO) in tablets, using methylene chloride:methanol:ammonia solution (25% NH₃) (8.8:1.3:0.1; v/v) as the mobile phase and Merck HPTLC plates (0.2 mm thickness) precoated with 60F254 silica gel on aluminium sheet as the stationary phase. Detection was carried out densitometrically using a UV detector at 230 nm. The retention factors of ATL and AMLO were 0.33 and 0.75, respectively. Calibration curves were linear in the range 10–500 μg ml⁻¹ for both. Assays of ATL and AMLO were 49.87 mg per tablet (relative standard deviation (R.S.D.), 1.3%) and 4.90 mg per tablet (R.S.D., 1.38%) for brand I, and 49.27 mg per tablet (R.S.D., 1.12%) and 4.98 mg per tablet (R.S.D., 1.42%) for brand II, respectively. The percentage recoveries for ATL and AMLO for brands I and II were 99.06 and 99.30%, and 99.27 and 99.15%, respectively.     

Simultaneous determination of aspirin and isosorbide 5-mononitrate in formulation by reversed phase high pressure liquid chromatography

A simple, precise and rapid reversed phase HPLC method was developed for the simultaneous estimation of aspirin (AS) and isosorbide 5-mononitrate (ISM) in combined formulation. The method was carried out on a Thermo Quest C18 column using a mixture of water:methanol (water pH adjusted to 3.4 using dilute orthophosphoric acid) and detection was carried out at 215 nm using chlorzoxazone as internal standard. Both the drugs showed linearity in the range of 2–10 μg/ml and limits of quantification was found to be 4 and 40 ng/ml for AS and ISM, respectively.     

HPLC法测定阿司匹林微囊中阿司匹林的含量

目的 建立检测阿司匹林微囊中阿司匹林含量的高效液相色谱分析法,为定量测定阿司匹林微囊中阿司匹林的含量提供检测手段.方法 用十八烷基硅烷键合硅胶为填充剂,以乙腈:0.1％磷酸为流动相(梯度洗脱:0min:乙腈:0.1％磷酸=10∶90;1 min:乙腈:0.1％磷酸=30∶70),在波长为276nm时进行检测,理论塔板数按阿司匹林峰计算不低于l 500.结果 阿司匹林和水杨酸分别在10～ 100μ g/ml (r=0.999 1)和4～40μg/ml (r=0.9995)浓度范围内呈良好的线性关系,平均回收率为96.91％,RSD=1.69％ (n=6).结论 本法具有简单、准确、灵敏度高的特点,适用于阿司匹林微囊中阿司匹林含量的测定.     

高效液相色谱法测定大鼠血浆中的二氯二茂钛

目的 建立反相高效液相色谱法测定大鼠血浆中有机金属抗癌原料药二氯二茂钛的含量.方法 采用Shimadzu VP-ODS色谱柱(250×4.6 mm,5 m),V(甲醇):V(醋酸铵)=55:45,pH 2.5为流动相,流速为1.0 ml/min,紫外检测波长254 nm,柱温室温,氨基比林为内标进行测定.血浆中生物样品采用液-液萃取法进行提取.结果 二氯二茂钛在大鼠血浆中的线性范围为10～120 μg/ml,回归方程为Y=57.83X-0.6042(r=0.9991,n=7),方法精密度RSD为1.8 %(n=6),平均回收率为RSD=1.63%(n=9).结论 方法简单快速,专属性强,可用于测定大鼠血浆中二氯二茂钛的含量,为该类药物的体内血药浓度检测和动力学研究提供了实验依据.     

Simultaneous HPLC analysis of pseudophedrine hydrochloride,codeine phosphate,and triprolidine hydrochloride in liquid dosage forms

An HPLC method using UV detection is proposed for the simultaneous determination of pseudophedrine hydrochloride, codeine phosphate, and triprolidine hydrochloride in liquid formulation. C18 column (250 mm × 4.0 mm) is used as the stationary phase with a mixture of methanol:acetate buffer:acetonitrile (85:5:10, v/v) as the mobile phase. The factors affecting column separation of the analytes were studied. The calibration graphs exhibited a linear concentration range of 0.06–1.0 mg/ml for pseudophedrine hydrochloride, 0.02–1.0 mg/ml for codeine phosphate, and 0.0025–1.0 mg/ml for triprolidine hydrochloride for a sample size of 5 μl with correlation coefficients of better than 0.999 for all active ingredients studied. The results demonstrate that this method is reliable, reproducible and suitable for routine use with analysis time of less than 4 min.     

HPLC法同时测定强力枇杷露中吗啡与可待因含量

目的 提高强力枇杷露的质量标准.采用高效液相色谱法对强力枇杷露中的吗啡与可待因进行含量的同时测定.方法 色谱柱为Agilent Eclipse C18色谱柱(4.6 mm×250 mm,5μm),以乙腈-0.01 mol·L-1磷酸二氢钾-磷酸-三乙胺溶液(5∶95∶0.2∶0.4)为流动相,流速1.0 mL·min-1,检测波长220 nm.结果 吗啡的进样量在0.229 3～4.586 μg范围内呈良好的线性关系(r=0.999 2),平均加样回收率为100.35％,RSD为2.87％(n=6);可待因的进样量在0.037 11～0.741 1μg范围内呈良好的线性关系(r=0.999 9),平均加样回收率为106.78％,RSD为2.09％(n=6).结论 方法经济合理、简便准确,可用于强力枇杷露中吗啡和可待因的含量测定.     

高效液相色谱法同时测定三黄片中的蒽醌类、黄酮类及生物碱类化合物

三黄片由大黄、黄芩浸膏和盐酸小檗碱组成，来源于祖国医学中的传统有效方剂——泻心汤，原方由大黄、黄芩、黄连三味药物组成。河北邯郸制药厂于1958年在大量研究的基础上将该方由传统的汤剂改为片剂，名“三黄片”。目前，全国有近200家企业生产三黄片。该方的主要有效成分是葸醌类、黄酮类和盐酸小檗碱。这3类成分文献报道的测定方法较多：大黄素等蒽醌类的测定方法有薄层扫描法、高效液相色谱法；黄芩苷的测定方法有极谱法、薄层扫描法、高效液相色谱法；     

Separation and determination of synthetic impurities of norfloxacin by reversed-phase high performance liquid chromatography

A simple and rapid high performance liquid chromatographic method for the separation and determination of synthetic impurities of norfloxacin was developed. The separation was achieved on a reversed-phase C₁₈ column using 0.01 M potassium dihydrogen orthophosphate and acetonitrile (60:40, v/v, pH 3.0) as mobile solvent at a flow rate of 1.0 ml/min at 40 °C and a UV detection at 260 nm. The method was used not only for quality assurance but also for monitoring the chemical reactions during the process development work in the laboratory. It was found to be specific, precise and reliable for determination of unreacted levels of raw materials, intermediates and the finished products of norfloxacin.     

Developing and optimizing a validated isocratic reversed-phase high-performance liquid chromatography separation of nimodipine and impurities in tablets using experimental design methodology

In the present study an isocratic reversed-phase high-performance liquid chromatography was investigated for the separation of nimodipine and impurities (A, B and C) using statistical experimental design. Initially, a full factorial design was used in order to screen five independent factors: type of the organic modifier – methanol or acetonitrile – and concentration, column temperature, mobile phase flow rate and pH. Except pH, the rest examined factors were identified as significant, using ANOVA analysis. The optimum conditions of separation (optimum values of significant factors) determined with the aid of central composite design were: (1) mobile phase: acetonitrile/H₂O (67.5/32.5, v/v), (2) column temperature 40 °C and (3) mobile phase flow rate 0.9 ml/min. The proposed method showed good prediction ability (observed–predicted correlation). The analysis was found to be linear, specific, precise, sensitive and accurate. The method was also studied for robustness and intermediate precision using experimental design methodology. Three commercially available nimodipine tablets were analyzed showing good % recovery and %RSD. No traceable amounts of impurities were found in all products.     

Factors affecting the retention of quaternary ammonium ions in reversed-phase high-performance liquid chromatography

The influence of solute structure (charge and hydrophobic substitution), organic modifier (type and concentration) and ion-pairing agent on the retention of nine quaternary- and bis-quaternary ammonium ions has been investigated in reversed-phase HPLC on ODS-silica. A functional group approach was taken to elucidate the influences of substitution on the charged nitrogen and the addition of a second positive charge to the solute molecule. These and other factors contributing to solute retention are discussed within the context of solvophobic theory. Hydrophobic effects and the solvation of the charged centre are shown to be the major factors contributing to retention in non-ion pair eluents. In addition, various electrostatic interactions in the mobile and stationary phases may contribute to solute retention in eluents containing an ion-pairing agent. It was found that ternary eluents containing hexane sulphonic acid and two organic modifiers offer certain selectivity advantages when compared with binary eluents.     

Simultaneous determination of losartan and hydrochlorothiazide in tablets by high-performance liquid chromatography

A method for the simultaneous determination of losartan potassium and hydrochlorothiazide in tablets is described. The procedure, based on the use of reversed-phase high-performance liquid chromatography, is linear in the concentration range 3.0-7.0 microg ml(-1) for losartan and 0.5-2.0 microg ml(-1) for hydrochlorothiazide, is simple and rapid and allows accurate and precise results. The limit of detection was 0.08 microg ml(-1) for losartan and 0.05 microg ml(-1) for hydrochlorothiazide.     

HPLC法同时测定阿咖片中咖啡因、阿司匹林、游离水杨酸的含量

目的:HPLC法测定阿咖片中咖啡因、阿司匹林及游离水杨酸的含量.方法:采用Phenomenex十八烷基硅烷键合硅胶柱;流动相:1%冰醋酸(用三乙胺调节pH至3.5)-甲醇(70:30);检测波长:280 nm;流量:1.0 mL*min-1.结果:咖啡因的线性范围9.0～108.0μg·mL-1,回归方程为Y=4.97×107X-8.5×103,r=0.9999,平均回收率为100.0%,RSD为0.3%;阿司匹林的线性范围7.5～900.0 μg·mL-1,回归方程为Y=4.60×106X+9.3×104,r=0.9999,平均回收率为99.8%,RSD为1.1%;水杨酸的线性范围3.0～3.6μg·mL-1,回归方程为Y=3.00×107X-3.4×104,r=0.999 8,平均回收率为101.6%,RSD为0.98%.结论: 该方法简便,结果准确.     

Simultaneous determination of serum flecainide and its metabolites by using high performance liquid chromatography

Simultaneous determination of serum flecainide and its oxidative metabolites was carried out by using high performance liquid chromatography (HPLC) equipped with conventional octadecylsilyl silica (ODS) column and fluorescence detector. Flecainide and its metabolites, m-O-dealkylated flecainide (MODF) and m-O-dealkylated lactam of flecainide (MODLF) in serum were extracted with ethyl acetate. The recoveries of flecainide, MODF and MODLF were greater than 92, 93, and 60% with the coefficient of variations (CVs) less than 3.2, 5.8, and 5.3%, respectively. The calibration curves were linear at the concentration range of 50–1500 ng/mL for flecainide and 10–500 ng/mL for MODF and MODLF (r>0.999). The CVs for intra-day assay were 2.7–5.3% for flecainide, 3.0–4.2% for MODF, and 3.7–4.3% for MODLF, respectively. The CVs for inter-day assay were 7.0–8.4% for flecainide, 3.3–6.7% for MODF, and 4.4–7.7% for MODLF, respectively. This assay method can be used for assessing the metabolic ability of flecainide in the patients with tachyarrhythmia.     

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.     

反相高效液相色谱法测定血清中丙戊酸浓度

目的建立适于普遍应用的丙戊酸血浓度测定方法.方法本文采用BrMMC将丙戊酸转化为可紫外检测的酯,再经RP-HPLC测定.结果在15～200μg*ml-1范围内,丙戊酸衍生物和内标的峰高比与浓度呈良好的线性关系,r=0.9991;平均回收率为100.9%.应用于34例患者的治疗药物监测,取得良好的临床效果.结论方法准确、灵敏、选择性强、重现性好,操作简便快速.本法适于临床研究与应用.     

HPLC同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量

目的 采用HPLC法同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量.方法 用1％冰乙酸的乙醇溶液处理供试品,采用Sepax GP-C18色谱柱(150 mm ×4.6 mm,5μn),0.2％ H3PO4水溶液-CH3 CN (79∶21)为流动相,流速1.0 mL·min-,柱温30℃,检测波长303 nm.结果 阿司匹林和水杨酸的线性范围分别为0.05 ～ 0.60 mg· mL-1(r=0.9993)和1.5 ～30 μg·mL-1(r =0.9999),平均加样回收率分别为97.00％ ～ 99.72％和98.25％ ～ 99.05(n =4).结论 所用方法简单、准确,可同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量.     

Simultaneous determination of valsartan and hydrochlorothiazide in tablets by first-derivative ultraviolet spectrophotometry and LC

First-derivative ultraviolet spectrophotometry and high-performance liquid chromatography (HPLC) were used to determine valsartan and hydrochlorothiazide simultaneously in combined pharmaceutical dosage forms. The derivative procedure was based on the linear relationship between the drug concentration and the first derivative amplitudes at 270.6 and 335 nm for valsartan and hydrochlorothiazide, respectively. The calibration graphs were linear in the range of 12.0–36.1 μg ml⁻¹ for valsartan and 4.0–12.1 μg ml⁻¹ for hydrochlorothiazide. Furthermore, a high- performance liquid chromatographic procedure with ultraviolet detection at 225 nm was developed for a comparison method. For the HPLC procedure, a reversed phase column with a mobile phase of 0.02 M phosphate buffer (pH 3.2)-acetonitrile (55: 45; v/v), was used to separate for valsartan and hydrochlorothiazide. The plot of peak area ratio of each drug to the internal standard versus the respective concentrations of valsartan and hydrochlorothiazide were found to be linear in the range of 0.06–1.8 and 0.07–0.5 μg ml⁻¹, respectively. The proposed methods were successfully applied to the determination of these drugs in laboratory-prepared mixtures and commercial tablets.