Bioavailability and Antidiabetic Activity of Gliclazide-Loaded Cubosomal Nanoparticles

In this study, gliclazide-loaded cubosomal particles were prepared for improving the oral bioavailability and antidiabetic activity of gliclazide. Four formulations of gliclazide-loaded cubosomal nanoparticles dispersions were prepared by the emulsification method using four different concentrations of glyceryl monooleate (GMO) and poloxamer 407 (P407) as the stabilizer. The prepared formulations were in vitro and in vivo evaluated. In vitro, the prepared gliclazide-loaded cubosomal dispersions exhibited disaggregated regular poly-angular particles with a nanometer-sized particle range from 220.60 ± 1.39 to 234.00 ± 2.90 nm and entrapped 73.84 ± 3.03 to 88.81 ± 0.94 of gliclazide. In vitro gliclazide release from cubosomal nanoparticles revealed an initially higher drug release during the first 2 h in acidic pH medium; subsequently, a comparatively higher drug release in alkaline medium relative to gliclazide suspension was observed. An in vivo absorption study in rats revealed a two-fold increase in the bioavailability of gliclazide cubosomal formulation relative to plain gliclazide suspension. Moreover, the study of in vivo hypoglycemic activity indicated that a higher percentage reduction in glucose level was observed after the administration of gliclazide cubosomal nanoparticles to rats. In conclusion, gliclazide-loaded cubosomal nanoparticles could be a promising delivery system for improving the oral absorption and antidiabetic activity of gliclazide.

Evaluation of a Modified Flow-Through Method for Predictive Dissolution and In Vitro/In Vivo Correlations of Immediate Release and Extended Release Formulations

The present study evaluated the ability of a modified flow-through method for predicting in vivo performance of immediate release (IR) and extended release (ER) formulations. In vitro dissolution of two model drugs, paracetamol IR tablets and felodipine ER tablets, was investigated under tuned conditions using the modified flow-through method and compared with the compendial quality control (QC) basket method. The in vivo absorption properties of paracetamol IR tablets and felodipine ER tablets were investigated in healthy volunteers. In vitro-in vivo correlation (IVIVC) analysis was performed based on the obtained in vitro and in vivo data. Our results demonstrated that the compendial QC method was not able to reflect in vivo actual absorption, while satisfactory discriminatory power and comparable in vitro dissolution/in vivo absorption were achieved for both paracetamol IR tablets and felodipine ER tablets by the modified flow-through method. This study indicated that the modified flow-through method is a potential tool to reflect in vivo performance of the IR and ER formulations.

Correction to: Predicting in vivo absorption of chloramphenicol in frogs using in vitro percutaneous absorption data

An amendment to this paper has been published and can be accessed via the original article.

IMMEDIATE RELEASE SOLID DISPERSION TABLET OF AZILSARTAN: FORMULATION STRATEGY TO ENHANCE ORAL BIOAVAILABILITY

Objective: Objective of the present study was to develop an immediate release solid dispersion tablet to enhance oral bioavailability of Azilsartan. Methods: Solid dispersion of azilsartan was developed using Soluplus® as a novel solubility enhancer by the solvent evaporation technique. 32factorial design was used in a fully randomized order to study effect of amount of azilsartan and Soluplus on solubility (µg/ml) and % drug dissolved in 30 min. Prepared solid dispersion was evaluated for different micromeritic properties, saturation solubility, and wettability. Then solid dispersion of all the batches compressed into an immediate-release tablet using sodium starch glycolate as a super disintegrant. Developed tablet formulations were evaluated for various post-compression parameters and satisfactory formulation among these were further studied for Fourier-transform infrared spectroscopy (FTIR), Differential Scanning Colorimeter (DSC), X-Ray Diffraction (XRD), in vivo absorption and stability study. Results: Results of micromeritic properties of solid dispersion showed that good flowability, compressibility, wettability, and saturation solubility. Post compression parameters of immediate-release tablets were found to be in acceptable limits. Batch ASD2 containing 40 mg Diacerein and 80 mg of Soluplus showed maximum drug release i.e. 99.82 % within 30 min. Compatibility study using FTIR, DSC, and XRD showed that drug is compatible with Soluplus. In vivo absorption study showed that, 2.67 fold increase in Area Under Curve (AUC) as compared to plain Azilsartan. Relative bioavailability was found to be 267.11 %. Results of stability study indicate that developed formulations were stable at accelerated temperature and humidity conditions. Conclusion: Study concluded that solid dispersion using Soluplus as a solubility enhancer is a suitable formulation strategy to enhance solubility, dissolution, and bioavailability of poorly water-soluble drug-like Azilsartan.