New HPLC Method with Experimental Design and Fluorescence Detection for Analytical Study of Antihypertensive Mixture,Amlodipine and Valsartan

New HPLC method was developed for determination of amlodipine and valsartan in their binary mixture as a part of routine control of combined formulations. The method was validated to meet official requirements including selectivity, stability, linearity, precision and accuracy. Chromatography was carried out using a LiChrospher RP-18 column, a mixture containing acetonitrile, phosphate buffer of pH 3.5 and methanol (45:45:10, v/v/v) and new fluorescence detection at 255 nm for excitation and 448 nm for emission. The effect of methanol content, pH of the buffer, flow rate, detection wavelengths and column temperature was estimated in robustness study, according to a plan defined by the Plackett-Burman design. For identification of significant effects, both graphical and statistical methods were used. Ro-bustness for dissolution test was checked estimating the effects of paddle speed, temperature and pH of dissolution medium. The method was proved to complying with all official guidelines. Therefore, it is suitable for determination of amlodipine and valsartan in their binary mixtures for different analytical and pharmaceutical purposes.

RP-HPLC Method for the Simultaneous Determination of Lisinopril and NSAIDs in API, Pharmaceutical Formulations and Human Serum

High performance liquid chromatographic method was developed valdated and applied for the simultaneous determi- nation of lisinopril and NSAIDs in bulk, pharmaceuticals formulations and human serum. A Purospher star C18 (5 μm, 25 × 0.46 cm) column was used with mobile phase consisting of methanol: water: acetonitrile (80:17.5:2.5 v/v, pH 3.0) and quantitative evaluation was performed at 225 nm with a flow rate of 1.0 mL?min–1. The retention time of lisinopril was 2.2 min while naproxen, flurbiprofen, diclofenac sodium and mefenamic acid were found to be 4.0, 4.5, 5.0 and 6.7 min respectively. Suitability of this method for the quantitative determination of the drugs was proved by validation in accordance with the requirements laid down by International Conference on Harmonization (ICH) guidelines. The method is selective, precise, accurate and can be used for analysis of pharmaceutical preparations in quality control and clinical laboratories.

Stability Indicating HPLC Method for Quantification of Solifenacin Succinate &Tamsulosin Hydrochloride along with Its Impurities in Tablet Dosage Form

A novel stability-indicating RP-HPLC method was developed and validated for simultaneous determination of Solifenacin Succinate & Tamsulosin Hydrochloride and its impurities in tablet dosage form. The method was developed using L1 column with gradient using the mobile phase consist of solvent-A (pH = 6.6, phosphate buffer + 0.5% Triethylamine) and solvent-B (90% Acetonitrile). The eluted compounds were monitored at 225 nm. Solifenacin Succinate & Tamsulosin Hydrochloride was subjected to oxidative, acid, base, hydrolytic, thermal and photolytic stress conditions. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection, limit of quantitation, accuracy, precision and robustness. The limit of quantification results was ranged from 0.135 - 0.221 μg/mL for Solifenacin Succinate impurities and 0.043 - 0.090 μg/mL for Tamsulosin Hydrochloride impurities. This method is suitable for the estimation of impurities and assay of Solifenacin Succinate & Tamsulosin Hydrochloride in tablets dosage form.

Development and Application of a Validated HPLC Method for the Determination of Clindamycin Palmitate Hydrochloride in Marketed Drug Products: An Optimization of the Current USP Methodology for Assay

A simple efficient isocratic reversed-phase HPLC method was developed and validated for the determination of clindamycin palmitate hydrochloride (CPH) and its commercially available oral solution products. Separation was achieved on a Phenomenex Zorbax (Luna) cyano column (150 × 4.6 mm, 5 μm) with a Phenomenex cyano guard cartridge (4 × 3.0 mm) on Agilent 1050 series HPLC system. CPH and its resolution standard lincomycin were eluted isocratically at a flow rate of 1 mL/min with a simplified mobile phase (potassium phosphate buffer (5 mM, pH 3.0)—acetonitrile—tetrahydrofuran (20:75:5, v/v/v)) and detected at 210 nm. The column was maintained at 25?C. The method was validated according to USP category I requirements. Robustness and forced degradation studies were also conducted. CPH marketed drug products were obtained from a drug distributor and assayed for potency using the validated method. Validation acceptance criteria were met in all cases. The analytical range for CPH was 15 - 500 μg/mL and the linearity was r2 > 0.999 over three days. The method was determined to be specific and robust. Both accuracy (92.0% - 103.8%) and precision (0.67% - 1.52%) were established across the analytical range for low, intermediate and high QC concentrations. Method applicability was demonstrated by analyzing two marketed products of CPH, in which results showed potency >98%. The method was determined to be an enhancement over the current USP methodology for assay as a result of increased efficiency, reduced organic solvents and the elimination of matrix modifiers. This method was successfully applied for the quality assessment of: 1) currently marketed drug products and 2) will in future assess the product quality of novel dosage forms of CPH for pediatric use.

Stability Indicating RP-HPLC Method for Quantification of Impurities in Valsartan and Hydrochlorothiazide FDC Tablet Dosage Form

A stability-indicating RP-HPLC method has been developed and validated for simultaneous determination of Valsartan & Hydrochlorothiazide and their impurities in FDC (Fixed Dose Combination) tablet dosage form. The method was developed using L1 column (250 × 4.6 mm;5 μm) with gradient elution using the mobile phase consisting of solvent-A (0.1% Ortho phosphoric acid) and solvent-B (100% Acetonitrile);the gradient program (Tmin/%B) was set as 0/10, 5/10, 20/60, 40/60, 41/10 and 50/10. The eluted compounds were monitored at 265 nm. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection, limit of quantitation, accuracy, precision and robustness. The influence of Acid, Alkaline, Oxidative, Photolytic, Thermal and Humidity stress conditions, on drug product was studied. The limit of quantification results of Valsartan, Hydrochlorothiazide and their impurities are, VAL: 0.303 μg/mL, HCTZ: 0.019 μg/mL, VAL RC-B: 0.085 μg/mL, VAL RC-C: 0.327 μg/mL, HCT RC-A: 0.017 μg/mL, CTZ: 0.080 μg/mL and 5-Chloro HCT: 0.047 μg/mL. The proposed method is suitable for the estimation of Valsartan & Hydrochlorothiazide impurities in tablets dosage form.

Validation of a HPLC Method for Quantification of Thiamine and Its Phosphate Esters in Rat Brain Tissue

The present data show a fast and efficient biological sample processing method for the extraction of thiamine (vitamin B1) and its mono-(TMP) and di-(TDP) phosphate esters from hippocampus, thalamus and prefrontal cortex (PFC) and blood sample of the rodents. In addition, using the hippocampus and standards of these three compounds we validated an isocratic fluorescence HPLC procedure for a simultaneous detection of them in a single chromatogram within a total run time of about 12 min. Reproducibility for TDP, TMP and B1 was 2.66%, 4.50% and 7.43% (intraday) and 37.54%, 25.39% and 25.87% (interday), respectively. Recovery assays were between 96.0% and 101.7%. The calibration curves were linear and the concentrations of the three compounds, all in nanomolar range, were determined in the brain areas and in the blood samples. When compared to the current methods in the literature, this new method provides information on essential variables, such as linearity range and limit of detection, reproducibility and stability of thiamine, TMP and TDP in rat brain samples. The present data on sample processing and B1 and its phosphate ester level determinations are the first to be validated using hippocampus samples of rats.

DEVELOPMENT OF A NOVEL HPLC METHOD FOR QUALITY CONTROL OF SAFFRON(CROCUS SATIVUS L.)

Saffron,the dried stigma of Crocus sativus L.,findsnumerous applications in TCM.Here,a novel HPLC protocol was established and applied for the analysis of saffron samples,not only from different places of origin but also from several harvest seasons.One of the main active constituents of saffron,crocin,is also contained in

Development of an HPLC–UV assay method for the simultaneous quantification of nine antiretroviral agents in the plasma of HIV-infected patients

A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etravirine lopinavir,raltegravir,rilpivirine and tipranavir in human plasma.For the first time we reported here the development and validation of an HPLC–UV assay to quantify the frequently administered 9antiretroviral compounds including dolutegravir and rilpivirine.A simple solid phase extraction procedure was applied to 500 μL aliquots of plasma.The chromatographic separation of the drugs and internal standard(quinoxaline) was achieved with a gradient of acetonitrile and sodium acetate buffer on a C_(18) reverse-phase analytical column with a 25 min analytical run time.Calibration curves were optimised according to the therapeutic range of drug concentrations in patients,and the coefficient of determination(r^2) was higher than0.99 for all analytes.Mean intraday and interday precisions(RSD) for all compounds were less than 15.0%,and the mean accuracy(% deviation from nominal concentration) was also found to be less than 15.0%.Extraction recovery range was between 80% and 120% for all drugs analysed.The solid phase extraction and HPLC–UV method enable a specific,sensitive,and reliable simultaneous determination of nine antiretroviral agents in plasma.Good extraction efficiency and low limit of HPLC–UV quantification make this method suitable for use in clinical trials and therapeutic drug monitoring.

HPLC-UV法测定舒肝和胃丸中α-香附酮和香附烯酮的含量

目的:建立舒肝和胃丸中α-香附酮和香附烯酮的高效液相色谱(HPLC-UV)含量测定法,为该制剂中醋香附含量的质量控制提供依据。方法:对舒肝和胃丸中α-香附酮和香附烯酮同时进行含量测定。采用Agilent ZORBAX SB-C18色谱柱(4.6 mm×250 mm,5μm),流动相为甲醇和水(65∶35),流速1.0 mL·min^(-1),检测波长254 nm,柱温30℃,进样量5μL。结果:采用该方法得到的舒肝和胃丸色谱图中,α-香附酮和香附烯酮色谱峰与相邻色谱峰分离效果较好,满足含量测定的要求;指标性成分α-香附酮、香附烯酮分别在0.08036~0.80360μg、0.2112~2.1120μg范围内线性关系良好,相关系数均为1.000;平均加标回收率分别为102.0%(RSD:1.6%,n=6),102.4%(RSD:2.0%,n=6);稳定性(24 h)、重复性、精密度良好。结论:本研究建立的α-香附酮和香附烯酮HPLC-UV含量测定方法简单、快捷、准确,可为舒肝和胃丸中醋香附含量的控制提供依据。

HPLC Determination of the Major Non-protein Amino Acids and Common Biogenic Amines in Lathyrus sativus Using a Novel Extraction Method

An assay is presented for simultaneously determining 5 biogenic amines and the major non-protein amino acids: the toxin β-N-oxalyl-L-α,β-diaminopropanoic acid (β-ODAP), its isomer α-ODAP and homoarginine in Lathyrus sativus extracts using the HPLC system after derivatization with para-nitrobenzyloxycarbonyl chloride (PNZ-Cl). However, it is more worthy of noting that this paper also describes a new extraction method using 0.2 mol/L HClO4. The new method has some advantages: shorter extraction-time, simultaneous extraction of free amino acids and polyamines, better inhibiting the isomerization of β-ODAP to α-ODAP, and so on.

HPLC法测定人血清及脑脊液中头孢他啶、头孢噻肟和头孢曲松的浓度

目的 建立高效液相色谱法(HPLC)测定血清/脑脊液中头孢他啶、头孢曲松、头孢噻肟的浓度,并应用于治疗药物监测。方法 色谱柱Diamonsil C18(250 mm×4.6 mm,5.0 μm);甲醇-0.01 mol/L磷酸二氢钾溶液(用甲酸调节pH值至3.0)为流动相,梯度洗脱;检测波长为254 nm;流速为1.0 mL/min;柱温25 ℃;头孢曲松和头孢噻肟作为内标。考察专属性、线性、精密度、稳定性、回收率等试验。结果 头孢他啶、头孢噻肟、头孢曲松的血清/脑脊液样品线性良好(r值均>0.999);三者血清/脑脊液的日内、日间精密度良好(RSD<5%),回收率在90%~110%之内;在室温24 h、冷藏48 h、反复冻融3次、样品处理后6 h、-20 ℃冷冻50 d等情况下均稳定(RSD<15%)。结论?该方法操作简便、准确、专属性强,可进行药物浓度监测,预防抗菌药物相关性脑病的发生。

Development and Validation of Stability Indicating RP-HPLC-PDA Method for Tenatoprazole and Its Application for Formulation Analysis and Dissolution Study

In the present study, comprehensive stress testing of tenatoprazole was carried out according to ICH guide-line Q1A (R2). Tenatoprazole was subjected to stress conditions of hydrolysis, oxidation, photolysis and neutral decomposition. Extensive degradation was found to occur in acidic, neutral and oxidative conditions. Mild degradation was observed in basic conditions. The drug is relatively stable in the solid-state. Successful separation of drug from degradation products formed under stress conditions was achieved on a Kromasil C18 column (250 mm × 4.6 mm, 5.0 μ particle size) using methanol: THF: acetate buffer (68:12:20 v/v) pH adjusted to 6.0 with acetic acid as mobile phase, flow rate was 1.0 mL●min–1 and column was maintained at 45°C. Quantification and linearity was achieved at 307 nm over the concentration range of 0.5 - 160 μg●mL–1 for tenatoprazole. The method was validated for specificity, linearity, accuracy, precision, LOD, LOQ and robustness.

Determination of Fenofibrate and the Degradation Product Using Simultaneous UV-Derivative Spectrometric Method and HPLC

Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm bivariate calibration derivative method, in which an optimum pair of wavelengths was chosen for the determination of different binary mixtures. In the second method (HPLC), separation was achieved on RESTEK Pinnacle II phenyl column (5 μm, 250 × 4.6 mm) and Pinnacle II phenyl (5 μm, 10 × 4 mm) guard cartridge using a mobile phase consisting of methanol –0.1% phosphoric acid (60:40, v/v) at a flow rate 2 mL●min–1, and the column oven temperature was set at 50°C. The UV detector was time programmed at 302 nm and 289 nm for the internal standard (I.S.) and fenofibrate, respectively. The proposed methods were successfully applied for the determination of fenofibrate and its degradation product in the laboratory-prepared mixture and in pharmaceutical formulation. The assay results obtained using the bivariate method were statistically compared to those of the HPLC method and good agreement was observed.

HPLC法测定乳苣不同部位菊苣酸含量

采用超声法提取乳苣不同部位总多酚,建立了测定乳苣不同部位菊苣酸含量的HPLC法,色谱条件为:岛津LC-16型高效液相色谱仪,SPD检测器,C18色谱柱(4.6 mm×150 mm,5μm),柱温为40℃,流动相为甲醇-0.1%磷酸,梯度洗脱,流速为1.0 mL·min^(-1),检测波长为280 nm,进样量为10μL。结果表明,菊苣酸浓度在11.6~58.0μg·mL^(-1)范围内与峰面积线性关系良好(R^(2)=0.9994),平均加标回收率为95.30%(n=6);乳苣根、茎、叶、全草中菊苣酸含量分别为23.70 mg·g^(-1)、37.20 mg·g^(-1)、114.24 mg·g^(-1)、102.50 mg·g^(-1),乳苣不同部位菊苣酸含量大小顺序为:叶>全草>茎>根。该方法简便、快速、准确,适用于乳苣中菊苣酸含量的测定。

Development of simple HPLC/UV with a column-switching method for the determination of nicotine and cotinine in hair samples

Nicotine and cotinine in hair are good biomarkers for assessing long-term exposure to smoking. However, analytical devices such as GC/MS are associated with high cost and are not widely used. HPLC/UV is used widely in laboratories, but is unsuitable for measurement of minor constituents, except when using the column-switching method. Thus, we aimed to establish a simple, inexpensive and sensitive method based on HPLC/UV with column switching for measuring nicotine and cotinine in hair. First, we compared the presence and absence of a column selection unit. We then measured amounts of nicotine and cotinine in hair samples collected from the general population, and compared both the corresponding levels and the detection limits with those in previous studies. Finally, initial and running costs of HPLC/UV were compared with other analytical methods. As one of the results, the areas of nicotine and cotinine measured by HPLC/UV with column-switching method were 12.9 and 16.9 times greater, respectively, than those without the column-switching method. The amount of nicotine and cotinine in hair was significantly correlated to number of cigarettes smoked per day (r = 0.228, p = 0.040). In addition, the HPLC/UV method showed similar sensitivity and detection limit (nicotine, 0.10 ng/mg;cotinine, 0.08 ng/mg) as reported in previous studies. The cost of the HPLC/UV method is lower than that of other analytical methods. We were able to establish a low-cost method with good sensitivity for measuring nicotine and cotinine in hair. The HPLC/UV with a column-switching method will be useful as a first step in screening surveys in order to better understand the effects of smoking exposure.

HPLC法测定葫芦七不同部位中7种倍半萜的含量

[目的]建立HPLC法测定葫芦七不同部位(根、茎、叶)中7种倍半萜类化合物的含量。[方法]采用Kromasil C_(18)(4.6 mm×250 mm,5μm)色谱柱,流动相为乙腈-水(40∶60);柱温35℃;检测波长240 nm;进样体积10μL。[结果]7种被测成分在测定质量浓度范围内线性关系良好(R^(2)≥0.9990);平均回收率在95.18%~97.61%,RSD在0.41%~1.60%;被检测的7种倍半萜类成分在葫芦七根、茎、叶不同部位中的含量差异明显,根中所含化合物的种类相对较多,含量相对较高。[结论]该方法快速、简便、准确,可用于葫芦七药材的质量控制。

Robustness Study and Superior Method Development and Validation for Analytical Assay Method of Atropine Sulfate in Pharmaceutical Ophthalmic Solution

Background: The robustness is a measurement of an analytical chemical method and its ability to contain unaffected by little with deliberate variation of analytical chemical method parameters. The analytical chemical method variation parameters are based on pH variability of buffer solution of mobile phase, organic ratio composition changes, stationary phase (column) manufacture, brand name and lot number variation;flow rate variation and temperature variation of chromatographic system. The analytical chemical method for assay of Atropine Sulfate conducted for robustness evaluation. The typical variation considered for mobile phase organic ratio change, change of pH, change of temperature, change of flow rate, change of column etc. Purpose: The aim of this study is to develop a cost effective, short run time and robust analytical chemical method for the assay quantification of Atropine in Pharmaceutical Ophthalmic Solution. This will help to make analytical decisions quickly for research and development scientists as well as will help with quality control product release for patient consumption. This analytical method will help to meet the market demand through quick quality control test of Atropine Ophthalmic Solution and it is very easy for maintaining (GDP) good documentation practices within the shortest period of time. Method: HPLC method has been selected for developing superior method to Compendial method. Both the compendial HPLC method and developed HPLC method was run into the same HPLC system to prove the superiority of developed method. Sensitivity, precision, reproducibility, accuracy parameters were considered for superiority of method. Mobile phase ratio change, pH of buffer solution, change of stationary phase temperature, change of flow rate and change of column were taken into consideration for robustness study of the developed method. Results: The limit of quantitation (LOQ) of developed method was much low than the compendial method. The % RSD for the six sample assay of developed method was 0.4% where the % RSD of the compendial method was 1.2%. The reproducibility between two analysts was 100.4% for developed method on the contrary the compendial method was 98.4%.

Comparison of HPLC-DAD and GC-FID Methods for Determination of 6-Methyl Coumarin in Cosmetics

The methods of determination of 6-methyl coumarin in cosmetics by HPLC-DAD and GC-FID were compared. The positive samples were confirmed by GC-MS. Methanol was used to extract 6-methyl coumarin from cosmetics. The chromatographic conditions of the two methods were optimized and the samples were determined. The recovery, precision, correlation coefficient, detection limit and quantitative limit of the two methods were compared. The results showed that the linear relationship between the two methods was good. The percentage recovery of standard addition by HPLC-DAD was 92.20%~102.80%, by RSD was 0.77%~2.00%;the detection limit was 0.05 mg/kg, the quantitative limit was 0.17 mg/kg. The percentage recovery of standard addition by GC-FID was 97.30%~103.28%, by RSD was 0.47%~4.87%;the detection limit was 1.3 mg/kg, the quantitative limit was 5.0 mg/kg. The detection limit by HPLC-DAD was lower and more sensitive than that by GC-FID , which also shows that HPLC-DAD has more advantages for the detection of low content samples.

HPLC法测定赖氨酸维B_(12)颗粒中香草醛的含量

目的:建立HPLC法测定赖氨酸维B_(12)颗粒中香草醛含量的方法。方法:取赖氨酸维B_(12)颗粒1.0 g,置10 mL刻度离心管中,加水1 mL溶解后,涡旋1 min,加甲醇至刻度后,继续涡旋1 min进行提取。采用Agilent C 18(250 mm×4.6 mm,5μm)色谱柱,流动相为甲醇-水(35:65),检测波长为277 nm。结果:本方法香草醛检出限为0.2μg·g^(-1),浓度在1.962~49.04μg·mL^(-1)的范围内呈线性关系(r=0.9999),低、中、高三水平回收率在91.86%~101.61%之间,RSD为2.9%(n=9)。测定样品6批,A企业4批,香草醛含量在55.18~79.55μg·g^(-1),B企业和C企业均未检出。结论:该方法操作简便,结果可靠,可用于赖氨酸维B 12颗粒中香草醛含量的测定。

HPLC法测定麻杏石甘口服液中甘草酸含量

试验旨在建立1种高效液相色谱法(HPLC)测定麻杏石甘口服液中甘草酸含量的分析方法。样品经流动相提取、过滤,注入高效液相色谱仪进行检测。色谱柱为Agilent ZORBAX SB-C18 (4.6 mm×250 mm,5μm),以甲醇-0.2 mol/L乙酸铵溶液-冰乙酸(体积比为67∶33∶1)为流动相,检测波长为250 nm,流速1.0 mL/min,柱温30℃,进样量10μL。结果表明,该方法在0.1~1.0 g/L范围内线性良好,甘草酸含量的线性方程为Y=7 767.13X-63.247,r=0.999 8。该方法具有较好的精密度、准确度和重复性,加样回收率为92.86%~96.19%,相对标准偏差值(RSD)均小于2.0%,适用于测定麻杏石甘口服液中甘草酸含量。