Simultaneous Estimation of Sacubitril and Valsartan Combination of Drug in Tablet Dosage Form Using Hydrotropy by UV Spectrophotometry

Sacubitril/valsartan, traded under the brand name Entresto between others, is a fixed-dose combination medication for use heart failure. Sacubitril is a neprilysin inhibitor (A prodrug) and is used in combination with valsartan to reduce the risk of cardiovascular events in patients with chronic heart failure. It is anti - hypertensive drug. Valsartan is an Angiotensin Receptor Blocker (ARB) that may be used to treat a variety of cardiac conditions including hypertension, diabetic nephropathy and heart failure. Two UV-spectrophotometric methods have been developed and validated for simultaneous estimation of Sacubitril and Valsartan in a tablet dosage form. The first method employed solving of simultaneous equations based on the measurement of absorbance at two wavelengths, 226.0 nm and 254.0 nm, 𝜆max for Sacubitril and Valsartan, respectively. The second method was absorbance ratio method, which involves formation of Q-absorbance equation at 240 nm (isoabsorptive point) and also at 254 nm (𝜆max of Valsartan). The methods were found to be linear between the range of 4-12 𝜇g/mL for Sacubitril and 2-10 𝜇g/mL for Valsartan using Methanol as solvent. The mean percentage recovery was found to be 96.68%and 101.89% for the simultaneous equation method and 100.2% and 104.53% for the absorbance ratio method, for sacubitril and valsartan respectively. It could be concluded from the results obtained in the present investigation that the two methods for simultaneous estimation of sacubitril and valsartan in tablet dosage form are simple, rapid, accurate, precise and economical and can be used, successfully, in the quality control of pharmaceutical formulations and other routine laboratory analysis. The reviewed highlights various analytical techniques such as high-performance liquid chromatography (HPLC), ultra- performance liquid chromatography (UPLC), UV Spectroscopy, high per-formance thin layer chromatography (HPTLC), liquid chromatography coupled to tandem mass spectrometry (LC- MS), RP-HPLC and other chromatographic method used. The combination of these drugs with different method was examine and the commonly use of the drugs in hypertensive.

SIMULTANEOUS ESTIMATION OF AZILSARTAN AND CILNIDIPINE IN BULK BY RP-HPLC AND ASSESSMENT OF ITS APPLICABILITY IN MARKETED TABLET DOSAGE FORM

Objective: This study aims to build up the RP-HPLC process for Azilsartan and Cilnidipine and authenticate the RP-HPLC process according to ICH validation code Q2R1. Methods: System suitability testing was performed to discover the qualifying criterion of the method by injecting the identical standard solution of Azilsartan 40μg/ml and Cilnidipine 10μg/ml in mixture/combination in subsequent optimized chromatographic conditions and the chromatogram was recorded. Moreover, the planned method was validated as per ICH guideline Q2R1 for the following parameters: linearity and range, precision, accuracy, robustness, and determined % recovery. Results: The outcomes of %RSD for retention time and peak area were found to be 0.65 and 1.32 for Azilsartan and 0.85 and 1.90 for Cilnidipine. The correlation coefficient, y-intercept, slope of the regression line were 0.9996,-1127.1, 3313.9, and 0.9993, 1460.2, 2876.4 for Azilsartan and Cilnidipine, respectively. Moreover, the range of this method was observed to be 40-240μg/ml and 10-60 μg/ml for Azilsartan and Cilnidipine, standard concentrations respectively. The % RSD achieved for precision (repeatability) was observed in the range of 1.57 to 2.43 for Azilsartan and 0.70 to 1.88 for Cilnidipine. The % accuracy was found in the range of 96.96 to 101.92% w/w for Azilsartan and 99.19 to101.96%w/w for Cilnidipine. The percent recovery values achieved for Azilsartan were in the range of 99.87 to 106.39% w/w and for Cilnidipine in the range of 94.51 to 105.96% w/w. Conclusion: The author concludes that the simultaneous estimation of Azilsartan and Cilnidipine with predefined objectives was successfully achieved. Moreover, the method was found to be steadfast for the quantification of Azilsartan and Cilnidipine in marketed tablet dosage forms.

SIMULTANEOUS DETERMINATION OF TIGECYCLINE AND ITS POTENTIAL IMPURITIES BY A STABILITY-INDICATING RP-HPLC-UV DETECTION TECHNIQUE

Objective: Stability representing the RP-HPLC method was established for synchronized quantification of Tigecycline and its impurities. This method was confirmed for its applicability to both tablet dosage and bulk drug forms. Methods: Intended for an isocratic elution, a mobile phase containing methanol: 10 mmol Triethylamine Buffer mixture (75:25 v/v, pH 6.1) was used at 1 ml/min flow rate and Agilent ZORBAX Eclipse XDB C18 (250 mm × 4.6 mm, 5 μm) column. Results: At 231 nm as wavelength, high-pitched peaks of Tigecycline (Tig) and its impurities (1and2) were detected at 6.55, 8.73 and 4.87 min correspondingly. The linearity of tigecycline and its impurities (impurity-1 and 2 and) were estimated with ranging from 75–450 µg/ml for Tigecycline and 1–6 µg/ml for both impurity 1 and 2. The corresponding recognition limits (LOD and LOQ) of the tigecycline and its impurities were originated to be (1.37,0.047 and 0.071 µg/ml) and (4.15, 0.143 and 0.126 µg/ml). Conclusion: The technique was effectively stretched for stability signifying studies under different stress conditions. Justification of the method was done as per the current ICH guidelines.

HPLC determination of Escitalopram in tablet dosage forms

Purpose: A simple, specific, precise, and accurate reversed phase liquid chromatographic (RP-LC) method has been developed for the determination of Escitalopram in tablet dosage form. Methods: The chromatographic separation was achieved on a LiChrosorb C18, 250 mm x 4.6 mm, 5 μm column at a detector wavelength of 270 nm and a flow rate of 1.0 ml/min. The mobile phase was composed of methanol, acetonitrile (70:30 v/v). The retention time of Escitalopram was 5.49 min. The method was validated for the parameters like specificity, linearity, precision, accuracy, limit of quantitation and limit of detection. Results: The method was found to be specific as no other peaks of impurities and excipients were observed. The square of correlation coefficient (R2) was 0.9999 while relative standard deviations were found to be <2.0%. Conclusion: The proposed RP-LC method can be applied for the routine analysis of commercially available formulations of Escitalopram.

A novel simultaneous high performance liquid chromatography-PDA method for the determination of Tenofovir AF, Darunavir, Emtricitabine and Cobicistat in bulk and its application to marketed formulation

Background The present research article involves the simultaneous determination of Tenofovir alafenamide, Darunavir, Emtricitabine and Cobicistat in bulk as well as in tablet dosage form using high performance liquid chromatography. Result The separation was performed using DIKMA Spursil, C18, ODS, (4.6 × 150 mm × 5 µm) analytical column using the mobile phase acetonitrile and 0.1% Orthophosphoric acid in the volume ratio of 70:30 at pH 3. The eluents were detected using PDA detector at 254.0 nm. After optimization subsequent validation study of different parameters was performed by utilizing the optimised condition as per the ICH guidelines. Under this optimised conditions Tenofovir alafenamide, Darunavir, Emtricitabine and Cobicistat were eluted at 2.287 min, 2.507 min, 4.062 min, 6.011 min respectively. Percentage assay was found 99.21% for Tenofovir alafenamide, 99.80% for Darunavir, 99.80% for Emtricitabine and 99.84% for Cobicistat. Tenofovir alafenamide was found linear in the range of 2.0–10.0 µg/mL, Darunavir (160.0–800.0 µg/mL), Emtricitabine (40.0–200.0 µg/mL) and for cobicistat (30.0–150.0 µg/mL). The corelation coefficient was found 0.999 for all the APIs. The detection limit was found 0.14 µg/mL for Tenofovir alafenamide, 2.14 µg/mL for Darunavir, 0.6 µg/mL for Emtricitabine and 7.32 µg/mL for cobicistat. In the LOQ study the quantitation limit was found 0.47 µg/mL for Tenofovir alafenamide, 7.12 µg/mL for Darunavir, 2.10 µg/mL, for Emtricitabine and 24.42 µg/mL for cobicistat. Conclusion All the studied API’s has been highly resolute utilizing the optimised condition and found extremely suitable for the determination of all of them simultaneously in marketed dosage form as well as in the bulk form.

Method Development of an Analytical Procedure for the Determination of Clofarabine in Pharmaceutical Formulations

A novel, simple and economic high performance liquid chromatography (HPLC) method has been developed for the estimation of Clofarabine in bulk and tablet dosage form with greater precision and accuracy.The method was validated as per ICH guidelines. Validation studies demonstrated that the proposed HPLC method is simple, specific, rapid, reliable and reproducible. Hence the proposed method can be applied for the routine quality control analysis of Clofarabine in bulk and tablet dosage forms. All the components of the system are controlled using SCL-10Avp System Controller. Data acquisition was done using LC Solutions software.

VALIDATED STABILITY INDICATING SPECTROSCOPIC METHOD FOR ESTIMATION OF DEGRADATION BEHAVIOUR OF VALSARTAN AND HYDROCHLOROTHIAZIDE IN TABLET FORMULATION

A simple, accurate and precise UV spectrometric method has been developed for the simultaneous determination of valsartan and hydrochlorothiazide in tablet dosage form. Spectra of valsartan and hydrochlorothiazide in methanol and water (50:50 V/V) show λ max at 250.0 nm and 271.4 nm, respectively. Valsartan and hydrochlorothiazide are subjected to various stress conditions like acid, alkali, thermal and photolytic degradation. Beer’s law was obeyed in concentration range of 4- 24 µg mL-1 for valsartan and 0.5-3 µg mL-1 for hydrochlorothiazide at their respective wavelengths. The proposed method was successfully applied to tablet dosage form for determination of both drugs. The percentage recovery of valsartan and hydrochlorothiazide were found to be 100.19 % and 99.51 %, respectively. A novel accurate and precise stability indicating spectroscopic method has been developed for estimation of valsartan and hydrochlorothiazide.