Formulation and In vitro Evaluation of Carvedilol Transdermal Delivery System

Purpose: To develop and optimize carvedilol transdermal delivery system.Methods: Solvent casting method was used to prepare patches using polymethyl methacrylate (PMMA) and Eudragit E100 (EE100) polymers, dimethylsulfoxide (DMSO) penetration enhancer, dibutylphthalate (DBP) plasticizer and Tween 80 surfactant. A 23 factorial design was used based on three variables (PMMA, EE100, DMSO). at two levels Second order polynomial equations indicating interplay of ingredients were obtained by factorial design using SigmaTech software for 1, 4, 8 and 20 h release data. so the design was extended to central composite design (CCD). The target formulation was obtained from contour plots and evaluated for various physicochemical parameters. including in-vitro dissolution studies.Results: Curvature effect was observed in F1 to F8 formulations, highlighting the interplay of ingredients. The interaction term (X2X3)exhibited highest Sum of Squares SS ratio at 1, 4, and 8 h data with positive coefficients indicating interaction; and so extended to CCD. From contour plots target formulation, F19, was identified and evaluated. The release data, were subjected to kinetic analysis, which followed Higuchi (diffusion) model (R2 = 0.9886).Conclusion: F19 yielded release profile nearer to the theoretical predictions with R2 of 0.9888 and followed Higuchi kinetics. Thus, a diffusion-mediated carvedilol matrix patch was successfully developed.Keywords: Carvedilol, Central composite design, Drug release, Transdermal patch

DESIGN AND EVALUATION OF LIQUISOLID COMPACTS OF NEBIVOLOL HYDROCHLORIDE

Objective: The aim of this study was to investigate the potential of a liquisolid system to improve the dissolution rate and the bioavailability of nebivolol hydrochloride. Methods: Solubility of nebivolol was determined in different nonvolatile solvents to finalize the best nonvolatile vehicle having maximum solubility. The liquisolid compacts were prepared using Fujicalin as a carrier material, Aerosil 200 as a coating material, Polyethylene glycol 400 as a liquid vehicle, and Croscarmellose sodium as a super disintegrating agent. 23 full factorial design was used to optimize the formulation in which the drug concentration, PVP K 30, Excipient ratio (R), and nebivolol containing nonvolatile solvent liquid level were selected as independent variables by using design expert software. The eight liquisolid compact formulations were prepared. Nebivolol liquisolid compacts were evaluated for drug content, tablet hardness, Friability, disintegration, and dissolution. An in vivo study was carried out in male Wistar rats. Results: The solubility of nebivolol hydrochloride in polyethylene glycol 400 was found to be greater than the other nonvolatile solvents. The liquisolid system of nebivolol was formulated successfully using Fujicalin, Aerosil 200, and polyethylene glycol 400. In vitro evaluation parameters for the liquisolid compact were within the prescribed limits. It was found that optimized liquisolid tablet formulation showed higher dissolution than the marketed tablet, with 88.33±0.94 % drug release within 120 min and the drug release was more than 75 % in 30 min for nebivolol LS-3N, which is optimized. LS-3N liquisolid compacts follow the Peppas model and exhibited first-order release. Conclusion: The liquisolid compacts can be a promising alternative for the formulation of water-insoluble drug nebivolol hydrochloride with improved dissolution and bioavailability

BIOANALYTICAL RP-HPLC METHOD DEVELOPMENT AND VALIDATION OF CLOPIDOGREL BISULFATE IN WISTAR RAT PLASMA AND ITS APPLICATION TO PHARMACOKINETIC STUDY

Objective: A novel, simple, precise, accurate, sensitive, and reproducible HPLC method for determining clopidogrel bisulfate in Wistar rat plasma was developed and validated. Methods: The chromatographic separation was performed using Xterra C18 (250 x 4.6 mm, 5μ) column. Mobile phase composed of Acetonitrile ACN: 0.05M potassium dihydrogen orthophosphate buffer pH 4.2 and in the ratio of 75:25% v/v at a flow rate of 1.2 ml/min. Detection was carried out using a PDA detector at 220 nm. The bioanalytical clopidogrel method was validated as per ICH guidelines. Results: The selected chromatographic condition was found to efficiently separate clopidogrel bisulfate (RT-2.838 min). The calibration curve was linear over the concentration range 40-200 ng/ml in Wistar rat plasma with a correlation coefficient of 0.999, respectively. The precision study revealed that the cumulative percentage variation was within the acceptable limit, and accuracy research showed the value of mean percent recovery between 99.72-99.83 %. Conclusion: A simple, rapid, specific, accurate, and precise analytical method was developed and validated using Wistar rat plasma. The technique was strictly validated according to the ICH guidelines. Acquired results demonstrate that the proposed strategy can be effortlessly and advantageously applied for routine analysis of clopidogrel in the Wistar rat plasma

Chromatographic study of sitagliptin and ertugliflozin under quality-by-design paradigm

The present study entails the systematic development and validation of a stability-indicating RP-HPLC method for the analysis of sitagliptin and ertugliflozin in a fixed-dose combination. Analytical quality by design (AQbD) concepts were used to define critical method variables, employing Pareto risk assessment and a Placket-Burman screening design, preceded by a Box-Behnken design with response surface analysis to optimise critical method parameters such as % acetonitrile (X1), buffer pH (X2) and column oven temperature (X3). Multiple response optimisation (Derringer’s desirability) of variables was accomplished by studying critical analytical attributes, such as resolution, retention time and theoretical plates. The title analytes were separated effectively on a PRONTOSIL C18 column at 37 °C using a mobile phase of acetonitrile:acetate buffer, pH 4.4 (36:64 percent v/v), pumped at a flow rate of 1 mL/min, and UV detection at 225 nm. Linearity was observed over a concentration range of 25-150 µg/mL and 3.75-22.5 µg/mL at retention times of 2.82 and 3.92 min for sitagliptin and ertugliflozin, respectively. The method obeyed all validation parameters of the ICH Q2(R1) guidelines. The proposed robust method allows the study of the selected drugs in pharmaceutical dosage forms as well as in drug stability studies under various stress conditions

DEVELOPMENT OF QUANTITATIVE METHOD OF TULOBUTEROL HYDROCHLORIDE IN RAT PLASMA: VALIDATION AND APPLICATION TO PRECLINICAL PHARMACOKINETICS

Objective: A robust, simple, accurate, rapid, and selective bioanalytical high-performance liquid chromatography (HPLC) method was established and validated to determine the tulobuterol hydrochloride in rat plasma. Methods: The protein precipitation method deproteinated analyte from rat plasma using acetone. The analysis of tulobuterol hydrochloride from rat plasma was accomplished using a mobile phase comprising of methanol: potassium dihydrogen orthophosphate buffer (0.05M; pH 4.0) in 90:10 (v/v) ratio run at 1.0 ml/min flow rate. Separation was carried on BDS hypersil C18 column (4.6 mm × 250 mm; 5 µ) at ambient temperature employing a 996 photodiode array (PDA) detector at 228 nm. Results: The linearity model was exhibited from 100-500 ng/ml with a good correlation of 0.999. Tulobuterol hydrochloride was efficiently separated at a retention time of 7.281 min. The percent recovery rate was between 100.21-100.46 %. The accuracy, precision, robustness, and ruggedness study showed relative standard deviation (%RSD) was within 2% (acceptable limit), and that revealed the method was efficient, precise, reliable, and reproducible. Conclusion: A simple, accurate, suitable method to quantitate tulobuterol hydrochloride in rat plasma was established using HPLC employed with a PDA detector that overcomes the increased cost for analysis. The developed method was successfully validated in rat plasma