New analytical quality by design-oriented HPLC method with multiple response optimization (Derringer’s desirability function) was demonstrated for simultaneous analysis of three antidiabetic drugs (metformin hydrochloride/empagliflozin/linagliptin) in a fixed-dose combination. Central composite design was employed for systematic optimization of critical method parameters, namely, % organic phase (X1), aqueous phase pH (X2) and flow rate (X3) while resolution, capacity factor and theoretical plate number as critical analytical attributes. Effective chromatographic separation of title analytes was accomplished on Std. Discovery C18 column at 30°C with mobile phase comprising acetonitrile: phosphate buffer pH 5 (38:62% v/v), pumped at a flow rate of 1 mL/min by isocratic elution pattern and UV detection at 222 nm. The model is rectilinear in the range of 1.0–200, 0.2–40 and 0.1–20 μg/mL at retention times of 3.04, 3.93 and 5.99 min for metformin, empagliflozin and linagliptin, respectively. The method obeyed all validation parameters of ICH Q2(R1) guidelines. The proposed HPLC method was highly robust for method transfer, regulatory flexibility within design space and can be used for assay of pharmaceutical dosage forms comprising these analytes. The proposed method was applied for stability studies of drugs under various stress conditions.

Aim: Current work entails the analytical quality by design (AQbD) based robust HPLC method for real-time analysis of canagliflozin and metformin. Different pKa values of two drugs made their chromatographic separation critical. Materials and Methods: The critical method parameters were systematically optimized using factorial experimental design (central composite design) and contours were generated as a function of significant variables when analyzed in the modeling software. The method operable design region that control the variation in response is obtained from contour plot and verified experimentally. Results: Effective chromatographic separation of title analytes was accomplished on SPOLAR C 18 (250 x 4.6 mm, 5µ) column at 25°C with mobile phase comprising of phosphate buffer, pH 6.0 and acetonitrile (55:45 % v/v), pumped at a flow rate of 0.8 mL/ min by isocratic elution pattern and UV detection at 254 nm. The linear model was established in the range of 50-300 and 5-30 and µg/mL at retention times of 3.24 and 10.77 min for metformin and canagliflozin, respectively. Conclusion: Method obeyed all validation parameters of ICH Q2 (R1) guidelines and able to discriminate the Adduct generated upon drug degradation. The proposed method was pertinent for assay drugs and extended to quantify the drugs in prevalence of biological matrix.

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.

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.

The  present  investigation  aimed  to  prepare  a  self  micro  emulsifying  drug  delivery  system  (SMEDDS)  for  the dissolution enhancement of nebivolol hydrochloride.  The main objective of this work was to develop, characterize, and evaluate a solid SMEDDS prepared by using the adsorption technique of a liquid SMEDDS to improve the solubility and dissolution rate of nebivolol hydrochloride.   The excipients were chosen based on the high solubility of nebivolol hydrochloride, and their concentrations were optimized by constructing ternary phase diagrams.   Thirty-two combinations were prepared using oil (Labrafac Lipophile WL 1349), surfactant (Kolliphor RH 40), and co-surfactant (Gelucire 44/14).  Self-emulsification time, dilution studies, and thermodynamic stability studies were satisfactory.   The in vitro nebivolol release profile showed a faster rate of dissolution compared with the pure nebivolol hydrochloride suspension and marketed formulation.  The droplet size was in the range  of  132.8±22.1  to  955.7±15.5  nm  and  zeta  potential  in  the  range  -7.2±0.53  mV  to  -46.4±0.32  mV  for  the  selected formulations.  Formulation N17 (Labrafac Lipophile WL 1349 -10%w/w, Kolliphor RH40-72%w/w, Gelucire 44/14- 18%w/w) was considered as optimized formulation and showed drug release of 97.26 ± 1.16% in 0.1 N HCl in 120 minutes, the particle size of 132.8±22.1 nm and zeta potential of -46.4±0.32 mV.   Thus, the present studies ratify that the bioavailability was improved by nebivolol  SMEDDS  formulation.    The  optimized  liquid  SMEDDS  was  further  used  for  the  preparation  of  Solid  SMEDDS (S-SMEDDS) formulations by using adsorption carriers.   The optimized Solid SMEDDS formulation exhibited 95.38 ± 0.76% in vitro drug releases, which was significantly higher than that of the drug solution.  The optimized formulation of nebivolol-loaded S-SMEDDS exhibited complete in vitro drug release in 120 min as a compared pure drug solution.  The present result confirmed the potential use of SMEDDS to improve the dissolution and oral bioavailability of poorly water-soluble nebivolol.