Simultaneous Determination of Valsartan and Hydrochlorothiazide in Tablets by RP-HPLC

A simple, reproducible and efficient reverse phase high performance liquid chromatographic method was developed for simultaneous determination of valsartan and hydrochlorothiazide in tablets. A column having 200 × 4.6 mm i.d. in isocratic mode with mobile phase containing methanol:acetonitrile:water:isopropylalcohol (22:18:68:2; adjusted to pH 8.0 using triethylamine; v/v) was used. The flow rate was 1.0 ml/min and effluent was monitored at 270 nm. The retention time (min) and linearity range (μg/ml) for valsartan and hydrochlorothiazide were (3.42, 8.43) and (5-150, 78-234), respectively. The developed method was found to be accurate, precise and selective for simultaneous determination of valsartan and hydrochlorothiazide in tablets.     

HPTLC Method for the Simultaneous Estimation of Valsartan and Hydrochlorothiazide in Tablet Dosage Form

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the simultaneous estimation of valsartan and hydrochlorothiazide in combined dosage forms. The stationary phase used was precoated silica gel 60F₂₅₄. The mobile phase used was a mixture of chloroform: methanol: toluene: glacial acetic acid (6:2:1:0.1 v/v/v/v). The detection of spots were carried out at 260 nm. The method was validated in terms of linearity, accuracy, precision and specificity. The calibration curve was found to be linear between 300 to 800 ng/spot for valsartan and 100 to 600 ng/spot for hydrochlorothiazide. The limit of detection and the limit of quantification for the valsartan were found to be 100 and 300 ng/spot respectively and for hydrochlorothiazide 30 and 100 ng/spot respectively. The proposed method can be successfully used to determine the drug content of marketed formulation.     

RP-HPLC法测定贝那普利氢氯噻嗪片的含量

目的建立高效液相色谱法测定贝那普利氢氯噻嗪片的含量。方法采用Ultimate AQ-C18柱(250mm×4.6mm,5μm);以四氢呋喃-水-冰醋酸(250mL+750mL+4mL加入四丁基溴化铵1.0g)为流动相,检测波长:240nm;流速:1.5mL·min-1。结果盐酸贝那普利质量浓度在41.2⁴12.3μg·mL-1范围内呈线性,r=0.999 5,氢氯噻嗪质量浓度在51.0412.3μg·mL-1范围内呈线性,r=0.999 5,氢氯噻嗪质量浓度在51.0⁵09.6μg·mL-1范围内呈线性,r=0.999 8;盐酸贝那普利平均回收率在99.6%509.6μg·mL-1范围内呈线性,r=0.999 8;盐酸贝那普利平均回收率在99.6%¹01.6%之间,RSD小于2%,氢氯噻嗪平均回收率在99.3%101.6%之间,RSD小于2%,氢氯噻嗪平均回收率在99.3%¹00.7%之间,RSD小于2%。结论该方法操作简便、准确、灵敏、重复性好,可用于贝那普利氢氯噻嗪片的质量控制。     

Spectrophotometric and HPLC Methods for Simultaneous Estimation of Amlodipine Besilate, Losartan Potassium and Hydrochlorothiazide in Tablets

Two UV-spectrophotometric and one reverse phase high performance liquid chromatography methods have been developed for the simultaneous estimation of amlodipine besilate, losartan potassium and hydrochlorothiazide in tablet dosage form. The first UV spectrophotometric method was a determination using the simultaneous equation method at 236.5, 254 and 271 nm over the concentration range 5-25, 10-50 and 5-25 μg/ml for amlodipine besilate, losartan potassium and hydrochlorothiazide, respectively. The second UV method was a determination using the area under curve method at 231.5-241.5, 249-259 and 266-276 nm over the concentration range of 5-25, 5-25 and 10-50 μg/ml for amlodipine besilate, hydrochlorothiazide and losartan potassium, respectively. In reverse phase high performance liquid chromatography analysis is carried out using 0.025 M phosphate buffer (pH 3.7):acetonitrile (57:43 v/v) as the mobile phase and Kromasil C18 (4.6 mm i.d×250 mm) column as stationery phase with detection wavelength of 232 nm linearity was obtained in the concentration range of 2-14, 20-140 and 5-40 μg/ml for amlodipine besilate, losartan potassium and hydrochlorothiazide, respectively. Both UV-spectrophotometric and reverse phase high performance liquid chromatography methods were statistically validated and can be used for analysis of combined dose tablet formulation containing amlodipine besilate, losartan potassium and hydrochlorothiazide.     

RP-HPLC Method for Simultaneous Estimation of Frusemide and Amiloride Hydrochloride in Tablet Formulation

A new reverse phase high performance liquid chromatography method for the simultaneous estimation of frusemide and amiloride hydrochloride in tablet formulation is developed. The determination was carried out on a HIQ SIL, C18 (250×4.6 mm, 5 μm) column using a mobile phase of 50 mM phosphate buffer solution:acetonitrile (50:50 v/v, pH 3.0). The flow rate was 1.0 ml/min with detection at 283 nm. The retention time for frusemide was 3.038 min and for amiloride hydrochloride 10.002 min. Frusemide and amiloride hydrochloride showed a linear response in the concentration range of 20-200 μg/ml and 10-100 μg/ml, respectively. The results of analysis have been validated statistically and by recovery studies. The mean recoveries found for frusemide was 99.98% and for amiloride hydrochloride was 100.09%. Developed method was found to be simple, accurate, precise and selective for simultaneous estimation of frusemide and amiloride hydrochloride in tablets.     

Stability-Indicating RP-HPLC Method for Estimation of Miglitol in Bulk and Tablets

A selective and sensitive, stability-indicating reverse phase high performance liquid chromatography method has been first developed and validated for the estimation of miglitol in bulk and tablet dosages form. Samples were separated on a prepacked, Inertsil amino C(18) column (150×4.6 mm i.d.) using a mobile phase comprised of acetonitrile and monobasic sodium phosphate pH 7.5 (80:20, v/v) delivered at 1.5 ml/min flow rate. Detection was performed on a SPD-20A prominence UV/Vis detector at 220 nm. The retention time for miglitol was 13.93±0.0367. The method was validated in terms of linearity, precision, accuracy, ruggedness, and specificity, limit of detection and limit of quantification. The linearity (r(2)) and percentage recoveries of miglitol were 0.9986 and 99.85%. This method is suitable for routine estimation of miglitol in bulk and tablet dosages form.     

Validated HPTLC Method for Simultaneous Determination of Quinapril Hydrochloride and Hydrochlorothiazide in a Tablet Dosage Form

Quinapril hydrochloride and hydrochlorothiazide were simultaneously determined by HPTLC in pharmaceutical formulations. The drugs were separated on silica gel 60 F₂₅₄ plates using suitable combination of solvents as mobile phase. The validation parameters, tested in accordance with the requirements of ICH guidelines, prove the suitability of methods.     

RP-HPLC Estimation of Ramipril and Telmisartan in Tablets

A rapid high performance liquid chromatographic method has been developed and validated for the estimation of ramipril and telmisartan simultaneously in combined dosage form. A Genesis C18 column having dimensions of 4.6×250 mm and particle size of 5 μm in isocratic mode, with mobile phase containing a mixture of 0.01 M potassium dihydrogen phosphate buffer (adjusted to pH 3.4 using orthophosphoric acid): methanol:acetonitrile (15:15:70 v/v/v) was used. The mobile phase was pumped at a flow rate of 1.0 ml/min and the eluents were monitored at 210 nm. The selected chromatographic conditions were found to effectively separate ramipril (R_t: 3.68 min) and telmisartan (R_t: 4.98 min) having a resolution of 3.84. The method was validated in terms of linearity, accuracy, precision, specificity, limit of detection and limit of quantitation. Linearity for ramipril and telmisartan were found in the range of 3.5-6.5 μg/ml and 28.0-52.0 μg/ml, respectively. The percentage recoveries for ramipril and telmisartan ranged from 99.09-101.64% and 99.45-100.99%, respectively. The limit of detection and the limit of quantitation for ramipril was found to be 0.5 μg/ml and 1.5 μg/ml respectively and for telmisartan was found to be 1.5 μg/ml and 3.0 μg/ml, respectively. The method was found to be robust and can be successfully used to determine the drug content of marketed formulations.     

反相高效液相色谱法测定氢氯噻嗪片含量

目的 :建立以反相高效液相色谱法测定氢氯噻嗪片含量的方法。方法 :以ZORBAXC18 为色谱柱 ,0 02mol/L磷酸盐缓冲液 -甲醇 (80∶20)为流动相 ,紫外检测波长为226nm ,柱温为室温 ,进样量为20μl。结果 :氢氯噻嗪在0 006～0 303mg/ml浓度范围内线性关系良好 (r=1 0000 ,n=5) ,平均回收率为100 1 % ,RSD=0 43 % (n=9)。结论 :该法准确度高、精密度好、简便快速 ,可作为氢氯噻嗪片的含量测定方法。     

Simultaneous RP-HPLC Estimation of Cefpodoxime Proxetil and Clavulanic Acid in Tablets

A new, simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of cefpodoxime proxetil and clavulanic acid from pharmaceutical dosage forms. The method was carried out on a Zorbax Eclipse XDB 5 μ C 18 (150×4.6 mm) column with a mobile phase consisting of acetonitrile:50 mM potassium dihydrogen phosphate buffer (pH 3.0, 70:30 v/v) at a flow rate of 1.0 ml/min. Detection was carried out at 228 nm. Aspirin was used as an internal standard. The retention time of clavulanic acid, cefpodoxime proxetil and aspirin was 4.43, 6.44 and 5.6 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms.     

高效液相色谱法测定复方卡托普利片剂中氢氯噻嗪含量

目的探讨测定复方卡托普利片剂中氢氯噻嗪含量的高效液相色谱（HPLC）法。方法色谱柱为Hypersil CN柱（150mm×4．6mm,5μm）,流动相为甲醇-四氢呋喃-水（10：10：80,以磷酸调pH至2．86）,流速为1．0mL／min,检测波长为220nm。结果氢氯噻嗪质量浓度在26-130μg／mL范围内与峰面积线性关系良好,线性回归方程为A=55432C＋110698,r=0．9999（n=5）;氢氯噻嗪的平均回收率为100．56％,RSD：0．46％（n=5）。结论所用方法快速简捷、可靠、准确度高、重现性好,可用于测定复方卡托普利片剂中氢氯噻嗪的含量。     

Development and Validation of RP-HPLC Method for Simultaneous Estimation of Atorvastatin Calcium and Fenofibrate in Tablet Dosage Forms

A reverse phase high performance liquid chromatographic method was developed for the simultaneous estimation of atorvastatin calcium and fenofibrate in tablet formulation. The separation was achieved by Luna C18 column and methanol:acetate buffer pH 3.7 (82:18 v/v) as mobile phase, at a flow rate of 1.5 ml/min. Detection was carried out at 248 nm. Retention time of atorvastatin calcium and fenofibrate was found to be 3.02+0.1 and 9.05+0.2 min, respectively. The method has been validated for linearity, accuracy and precision. Linearity for atorvastatin calcium and Fenofibrate were in the range of 1-5 μg/ml and 16-80 μg/ml, respectively. The mean recoveries obtained for Atorvastatin calcium and fenofibrate were 101.76% and 100.06%, respectively. Developed method was found to be accurate, precise, selective and rapid for simultaneous estimation of atorvastatin calcium and fenofibrate in tablets.     

Development and Validation of a UV Spectrophotometric Method for the Simultaneous Estimation of Eprosartan Mesylate and Hydrochlorothiazide in Bulk and Formulations

A simple, efficient, precise and accurate absorbance ratio method have been developed for the estimation of eprosartan mesylate and hydrochlorothiazide in pure and in fixed dose combination. In this method, UV spectra of eprosartan mesylate and hydrochlorothiazide were overlayed which involves the formation of Q-absorbance equation at 249.1 nm (isobestic point) and 274.5 nm, the max of hydrochlorothiazide. Both the drugs obeyed Beers law in the concentration range of 6-36 μg/ml and 1-10 μg/ml for eprosartan mesylate and hydrochlorothiazide, respectively. The accuracy of the method was determined by recovery studies and was found to be in the range of 102.29-103.10% and 99.52-101.60% for eprosartan mesylate and hydrochlorothiazide, respectively. The method was validated as per ICH guidelines and statistically. The method showed good reproducibility and recovery with % RSD less than 2. The method was found to be simple, economic, accurate and reproducible and can be used for routine analysis of eprosartan mesylate and hydrochlorothiazide in pure and in fixed dose combinations.     

Simultaneous Spectrophotometric Estimation of Haloperidol and Trihexyphenidyl in Tablets

The combination of haloperidol and trihexyphenidyl is a dosage form to be used as antidyskinetic agent. Literature revealed that there is no single method for the simultaneous estimation of these drugs in tablet dosage form, which prompted us to develop a simple, rapid, accurate, economical and sensitive spectrophotometric method. The simultaneous estimation method is based on the principle of additivity of absorbance, for the determination of haloperidol and trihexyphenidyl in tablet formulation. The absorption maxima of the drugs were found to be at 245.0 nm and 206.0 nm respectively for haloperidol and trihexyphenidyl in methanol and 0.1N HCl (90:10). The obeyance of Beer Lambert’s law was observed in the concentration range of 2.5-12.5 µg/ml for haloperidol and 1.0-5.0 µg/ml for trihexyphenidyl. The accuracy and reproducibility of the proposed method was statistically validated by recovery studies.     

Analytical Method for the Simultaneous Estimation of Hydrochlorothiazide and Metoprolol Tartrate using RP HPLC

The present study deals with the estimation by RP-HPLC of two different drug components hydrochlorothiazide and metoprolol tartrate present in a tablet formulation. It is a simple, fast, precise and accurate high performance liquid chromatographic method. It is performed using phosphate buffer along with methanol as mobile phase, in the proportion of 60:40. The separation is done on a C(18) column and it is estimated at a λ(max) of 226 nm with a flow of 1 ml/min. The detection limits range from a 0.013 to 0.075 mg/ml for hydrochlorothiazide and 0.10 to 0.60 mg/ml for metoprolol tartrate, respectively. The specificity for interference of any peak with main peak of interest is checked. A scan of the individual drug was taken for assuring the λ(max). The system suitability by precision is also checked to ensure the analytical method. The method was found to be accurate and precise for estimation of the two drugs simultaneously.     

Development and Validation of Stability-indicating RP-HPLC Method for Estimation of Pamabrom in Tablets

The present study depicts the development of a validated RP-HPLC method for the determination of the pamabrom in presence of degradation products or other pharmaceutical excipients. Stress study was performed on pamabrom and it was found that it degrade sufficiently in acidic, alkali and oxidative condition but less degradation was found in thermal and photolytic condition. The separation was carried out on Enable G 120 A⁰ (250×4.6 mm, 5 μ) column having particle size 5 μ using methanol: water (75:25 v/v) with pH 4.0 adjusted with ortho phosphoric acid as mobile phase at flow rate of 1 ml/min. The wavelength of the detection was 280nm. A retention time (R_t) nearly 3.9 min was observed. The calibration curve for pamabrom was linear (r² = 0.9997) from range of 10-60 μg/ml with limit of detection and limit of quantification of 1.41 μg/ml and 4.28 μg/ml, respectively. Analytical validation parameter such as selectivity, specificity, linearity, accuracy and precision were evaluated and relative standard deviation value for all the key parameters were less than 2.0%. The recovery of the drug after standard addition was found to be 101.35%. Thus, the developed RP-HPLC method was found to be suitable for the determination of pamabrom in bulk as well as stability samples of tablets containing various excipients.     

RP-HPLC Method for Simultaneous Estimation of Nitazoxanide and Ofloxacin in Tablets

A reverse phase high performance liquid chromatography method was developed for simultaneous estimation of nitazoxanide and ofloxacin in tablet formulation. The separation and quantification was achieved by Hiq Sil C₁₈V Size 4.6 mm Ø ^*250 mm column in isocratic mode, with mobile phase consisting of acetonitrile-methanol-0.4 M citric acid, (60:30:10, v/v/v). Citric acid used to stabilize nitazoxanide and ofloxacin in mobile phase. The mobile phase was pumped at a rate of 0.6 ml/min and the detection was carried out at 304 nm. The retention time of ofloxacin and nitazoxanide was found to be 3.122 and 5.902 min, respectively. The method was validated for linearity, accuracy, and precision. Linearity for ofloxacin and nitazoxanide were in the range 2-36 μg/ml and 5-90 μg/ml, respectively. The developed method was found to be accurate, precise and selective for simultaneous estimation of ofloxacin and nitazoxanide in tablets.     

Development and Validation of an RP-HPLC Method for Quantitative Estimation of Eslicarbazepine Acetate in Bulk Drug and Tablets

A convenient, simple, accurate, precise and reproducible RP-HPLC method was developed and validated for the estimation of eslicarbazepine acetate in bulk drug and tablet dosage form. Objective was achieved under optimised chromatographic conditions on Dionex RP-HPLC system with Dionex C18 column (250×4.6 mm, 5 μm particle size) using mobile phase composed of methanol and ammonium acetate (0.005 M) in the ratio of 70:30 v/v. The separation was achieved using an isocratic elution method with a flow rate of 1.0 ml/ min at room temperature. The effluent was monitored at 230 nm using diode array detector. The retention time of eslicarbazepine acetate is found to be 4.9 min and the standard calibration plot was linear over a concentration range of 10-90 μg/ml with r²=0.9995. The limit of detection and quantification were found to be 3.144 and 9.52 μg/ml, respectively. The amount of eslicarbazepine acetate in bulk and tablet dosage form was found to be 99.19 and 97.88%, respectively. The method was validated statistically using the percent relative standard deviation and the values are found to be within the limits. The recovery studies were performed and the percentage recoveries were found to be 98.33± 0.5%.     

高效液相色谱法测定氢氯噻嗪片的含量

目的建立测定氢氯噻嗪片中氢氯噻嗪含量的高效液相色谱（HPLC）法。方法采用HypersilC18柱（150mm×4．6mm,5μm）,以乙腈-水（12：88）为流动相,流速为1．0mL／min。检测波长为271nm。结果氢氯噻嗪质量浓度线性范围为2．05～10．25μg／mL,r=0．99999（n=5）,平均回收率为98．48％,RSD=0．59％（12=6）。结论HPLC法准确、可靠,适用于测定氢氯噻嗪片中氢氯噻嗪的含量。