Quantification Of Valsartan Research Articles

Development and Validation of a Bioanalytical HPLC Method for Quantification of Valsartan in Human Plasma and its Application in Pharmacokinetics Studies

Simple, sensitive, accurate and validated bioanalytical liquid chromatographic procedure coupled with fluorescence detector for estimation of valsartan in presence of diclofenac as internal standard (IS) in plasma has been established. The extraction of valsartan and IS was achieved using methyl tertiary-butyl ether: ethyl acetate (2:8) mixture and the extracted samples were separated on Waters, Xterra- C18 (150 x 4.6 mm, 5 μm) column with 1.0 mL/min flow rate. The detection has been performed at excitation and emission λ at 255 nm and 374 nm, respectively. The elution of the analytes was achieved using acetonitrile: phosphate buffer containing 1 g/L sodium salt of 1-Hexane sulphonic acid with pH adjusted to 2.5 with orthophosphoric acid (52:48, v/v) as an eluting system. The standard curves were linear from 5.0-4000.0 ng/ mL. Method validation has been prepared as per FDA guidelines. Good extraction recoveries of 87.22 % and 99.33 % for valsartan and IS have been acquired, respectively. The achieved values of accuracy and precision were in the adequate range. The proposed procedure was conducted effectively for analysis of valsartan after a single oral administration of one tablet of Tareg tablets ® (80 mg valsartan) to six healthy volunteers.

Stability Indicating HPTLC Method for Simultaneous Estimation of Sacubitril and Valsartan in their Pharmaceutical Dosage Form

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and completely validated for the estimation of Valsartan and Sacubitril in pharmaceutical dosage forms. Quantification of Valsartan and Sacubitril were carried out with precoated silica gel aluminum Plate 60 F254, (20 cm ×10 cm) 100 μm thickness as stationary phase. Toluene: Methanol: Ethyl Acetate: Glacial Acetic acid (8:2:1:1 % v/v/v). The optimized chamber saturation time before chromatographic development was 20 min at room temperature (25ºC ± 2). The length of chromatographic run was 8 cm which took average 15 min to develop. Densitometry scanning was performed using Camag TLC scanner IV with Win CATS software (V 1.4.6.2002, Camag). Optimized chromatogram of Valsartan and Sacubitril having Rf of 0.43 and 0.33, respectively. Linear relationship between peak area and concentration of standard was evaluated over the concentration range expressed in ng/band by making five replicate measurements in the concentrations range of 400-1400 ng/band and 4000-14,000 ng/band, respectively for Valsartan and Sacubitril. Literature reveals that there was no any method developed using HPTLC in simultaneous estimation of Valsartan and Sacubitril in their pharmaceutical dosage form. The proposed method can be successfully applied for the estimation of drug content of different marketed formulations.

Validation of an analytical method for the determination of valsartan in human plasma by HPLC/UV with addition standard using losartan as an internal standard.

Introduction: The validation concept refers to the statistical evaluation of the results obtained in the application of analytic technics, by appropriately documented and demonstrative tests that a method is sufficiently reliable to produce the result foreseen under defined conditions, like they are: analytic system, concentration interval, infrastructure and human talent. Objective: To describe the validation process of the analytic method for the valsartan quantification in human plasma by HPLC-UV and its application in pharmacokinetic, bioavailability and bioequivalence studies of products that contain the active principle valsartan. Methodology: A method for detection and quantification of valsartan in human plasma has been developed using an isocratic elution on reversed phase liquid chromatography with ultraviolet detection at a single wavelength (265 nm) and the addition standard method. Losartan was used as an internal standard. This method involves a solid-phase drug extraction (valsartan and losartan) from plasma using C8 cartridges. Separation was achieved on a C18 reversed phase column and the mobile phase consisted of 45% acetonitrile and 55% phosphate buffer (adjusted to pH 2.7 ± 0.1 with phosphoric acid). The assay has been vali-dated over a concentration range of 0.05 to 20 µg/ml with addition of valsartan 2.5 µg/ml. Results and conclusions: Calibration curve was linear in the described concentration range. The reproducibility, stability and recovery of the method were evaluated. Determination of valsartan in human plasma by HPLC/UV method was accurate and precise with a quantitation limit of 1.485 µg/ml. The method was sufficiently sensitive for pharmacokinetic studies of valsartan in human plasma.