Sustained-Release Solid Dispersion of High-Melting-Point and Insoluble Resveratrol Prepared through Hot Melt Extrusion to Improve Its Solubility and Bioavailability

This study aimed to prepare a sustained-release solid dispersion of poorly water-soluble resveratrol (RES) with high melting point in a single hot melt extrusion step. A hydrophobic–hydrophilic polymeric blend (Eudragit RS and PEG6000) was used to control the release of RES. With the dispersive mixing and high shear forces of hot melt extrusion, the thermodynamic properties and dispersion of RES were changed to improve its solubility. The effects of the formulation were investigated through univariate analysis to optimize the preparation of the sustained-release solid dispersion. In vitro and in vivo studies were performed to evaluate the prepared RES/RS/PEG6000 sustained-release solid dispersion. The physical state of the solid dispersion was characterized using differential scanning calorimetry and X-ray diffraction. Surface properties of the dispersion were visualized using scanning electron microscopy, and the chemical interaction between RES and excipients was detected through Fourier-transform infrared spectroscopy. Results suggested that the optimized sustained-release solid dispersion was obtained when the mass ratio of RES-polymeric blend was 1:5, the ratio of PEG6000 was 35%, the barrel temperature was 170 °C, and the screw speed was 80 rpm. In vitro studies demonstrated that the solid dispersion showed a good sustained release effect. The cumulative release of RES reached 82.42% until 12 h and was fit by the Weibull model. In addition, the saturated solubility was 2.28 times higher than that of the bulk RES. In vitro studies demonstrated that the half-life increased from 3.78 to 7.09 h, and the bioavailability improved to 140.38%. The crystalline RES was transformed into the amorphous one, and RES was highly dispersed in the polymeric blend matrix.

Influence of electron beam irradiation on the mechanical properties of pbat/pla polymeric blend / Influência da irradiação por feixe de electrões nas propriedades mecânicas da mistura polimérica pbat/pla

The aim of this research was to evaluate the changes in the mechanical properties of poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymeric blend after the radiation process at different radiation doses. The irradiation was performed in an electron beam accelerator, with 1.5 MeV of energy and 25 mA electric current. The samples were irradiated with doses of 5, 10, 15, 25, 50, 65 and 80 kGy. Both irradiated and non-irradiated samples were characterized by Izod pendulum impact resistance and tensile strength at rupture. The results showed an increase of 44% in relation to Izod impact resistance at a dose of 65 kGy. However, the module of elasticity decreased 56% and tensile strength at rupture decreased 55% at the same radiation dose. In relation to elongation, significant alterations caused by electron beam irradiation was not observed. Therefore, it can be concluded that irradiated blends could be used to make environmentally friendly products, which could absorb impact energy.

EFFECT OF POLYMERIC BLEND ON EX-VIVO PERMEATION STUDIES OF ACECLOFENAC LOADED FILM FORMING GEL

Objective: To date, film-forming systems have been intensively investigated for transdermal drug delivery. Film-forming systems offers various advantages compared over conventional transdermal drug delivery systems. The objective of the present study was to study the effect of polymeric blend on ex-vivo permeation studies of topical film-forming gel of aceclofenac. Methods: Film-forming gels were prepared by using Hydroxypropyl methylcellulose and Eudragit polymeric blend in varied concentrations, polyethylene glycol 400 as plasticizer, ethanol as solvent and tween 80 as a penetration enhancer. The prepared film-forming gels were evaluated and the influence of the concentration and ratio of polymeric blends used plasticizer and ethanol were investigated. Results: All the prepared film-forming gels showed satisfactory properties regarding homogeneity, compatibility, viscosity and pH value. Variation in the concentration of polymers showed a variable effect on drug permeation rate from film-forming gels. Almost, all formulations permeated up to 80% of drug in 12 h and formulation F1 showed a maximum release about 97.54 % in 12 h. Conclusion: Film-forming gels of aceclofenac with sustained-release profile were successfully developed and may provide a promising effective formulation which may improve patient compliance.

Effect of Mechanical Properties in Enhanced Polymeric Blend Membranes

This study was carried out to evaluate the effect of blending the rubbery and glassy polymer with an alkanolamine on the mechanical properties. Due to the intrinsic properties of glassy polysulfone (PSU) and rubbery polyvinyl acetate (PVAc), optimizing their properties by blending both polymers is expected to address the shortage. The enhanced polymeric blend membrane (EPBM) was developed by varying the composition of PVAc ranging from 5 to 20 wt. % with 95 to 80 wt. % base PSU in dimethyl- acetamide (DMAc) solvent. The DEA amine composition was added to the blend and kept at 10 wt. % over solvent. The tensile analysis technique is utilized to evaluate the mechanical behaviour of a polymeric material which comprises the deformation of the polymeric material underneath the effect of an applied force prior to failure. The mechanical analysis showed improvement in tensile strength, Young's modulus and elongation at break properties with the increase in PVAc/DEA composition in the enhanced polymeric blend membranes. The elongation at break property increased with an increase in the amine contents which indicated the flexibility of the EPBM. In addition, the mechanical analysis revealed remarkable enhancement in the mechanical properties of the EPBM which might be attributed to the robust interactions among the PSU blend with PVAc and DEA.