Solubility enhancement of fexofenadine using self-nano emulsifying drug delivery system for improved biomimetic attributes

BACKGROUND

Fexofenadine is a poorly water-soluble drug, which limit its bioavailability and ultimately therapeutic efficacy. Liquid self-nano emulsifying drug delivery system (L-SNEDDs) is an approach that can enhance the solubility of fexofenadine by increasing its surface area and reducing the particle size, which increases the rate and extent of drug dissolution.

METHOD

In this investigation, L-SNEDDs of fexofenadine was made up using surfactants and co-surfactant. The SNEDDS formulation was optimized using a pseudo-ternary phase diagram and characterized.

RESULTS

The optimized L-SNEDDS incorporated fexofenadine were thermodynamically stable and showed mean droplet size and zeta potential of 155nm and -18mV, respectively unaffected by the media pH. In addition, the viscosity, and refractive index were observed 18.4 and 1.49 cps, respectively for optimized L-SNEDDS fortified fexofenadine. The results of Fourier transform infrared spectroscopy revealed an insignificant interaction between the fexofenadine and excipients. A drug loading efficiency of 94.20% resulted with a complete in vitro drug release in 2h, compared with the pure drug, which demonstrate significant improvement in the efficacy. Moreover, these results signify that on further in vivo assessment L-SNEDDS fortified fexofenadine can indicate improvement in pharmacokinetic and clinical outcome.

CONCLUSION

Thus, the investigation revealed that, the L-SNEDDs incorporated fexofenadine was most effective with a mixture of surfactant and co-surfactant with improved solubility intend to relieve pain associated with inflammation with single-dose oral administration.

D-optimal mixture design inspired modified release tablet formulation of lamotrigine for the treatment of seizures: An in-depth characterization

OBJECTIVE

Lamotrigine (LTG) an anticonvulsant drug with a dissociation constant (pKa: 5.7), suffers from enhanced blood plasma spike after each dose, when administered as fast release tablet. Being BCS class-II candidate and pH dependent solubility, development of release-controlled tablets of LTG is a major challenge. This investigation aims at designing the release-controlled tablet (RCT) formulation of LTG using a solid dispersion (SD) technique via addressing its solubility and release problems.

MATERIAL AND METHODS

RCT of LTG was fabricated using SD blend of Eudragit RL and Eudragit RS and PVP K-30 with different polymer blend ratio (1:5 and 1:7). The optimization of RCT of LTG was performed using D-optimal mixture design with three independent variables, three response variables, and one constraint. The dissolution rate was determined and data were then fitted to different mathematical models. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies and tableting parameters were analyzed.

RESULT

In vitro studies of predicted optimized batches (POBs) have shown that drug release over a period of 12hours was 88.05±3.4% in media I, 86.10±3.7% in media II and 85.84±4.2% in media III. An in vitro kinetic model equating R2-value for all the tested models indicated that the first order and Higuchi release kinetics model were the most appropriate.

CONCLUSION

Based on the optimized formulation consisting of SD of LTG with Eudragit RL, Eudragit RS and PVP K-30, the release rate was consistently similar throughout the GI tract, regardless of the pH of the environment.

Solubilization of drugs using beta-cyclodextrin: Experimental data and modeling

Many drug candidates fail to complete the entire drug development process because of poor physicochemical properties. Solubility is an important physicochemical property which plays a vital role in various stages of drug discovery and development. Several methods have been proposed to enhance the solubility of drugs, and complex formation with cyclodextrins is among them. Beta-cyclodextrin (βCD) is a common excipient for solubilization of drugs. The aim of this study is to develop the mechanistic QSPR models to predict the solubility enhancement of a drug in the presence of βCD. In this study, the solubility enhancement of some drugs in the presence of 10mM βCD at 25°C was experimentally determined or collected from the literature. Two different models to predict the solubilization by βCD were developed by binary logistic regression using structural properties of drugs with more than 80% accuracy. Polar surface area and excess molar refraction are the main parameters for estimating solubilization by βCD. Moreover, other descriptors related to hydrophobicity and the capability of hydrogen bonding formation of molecules could improve the accuracy of the established models.

Effect of temperature and propylene glycol as a cosolvent on dissolution of clotrimazole

Herein, the solubility study of clotrimazole was performed in a propylene glycol+water system. The solubility values were fitted to various cosolvency equations. The model accuracies were studied with the computation of the mean relative deviations. The thermodynamic behavior was investigated according to the van't Hoff and Gibbs equations for clotrimazole in the propylene glycol+water system. Furthermore, the density data for clotrimazole were determined in mixtures of propylene glycol+water and fitted to the Jouyban-Acree equation.