Optimization of paeonol-loaded microparticle formulation by response surface methodology.

In this study, a central composite rotatable design based on response surface methodology (RSM) was employed to design and formulate an appropriate paeonol microparticle formulation. Five levels of a three-factor, rotatable, central composite design were used to evaluate the critical formulation variables. The optimum conditions for preparing paeonol-loaded microparticles were predicted to be: polyvinyl alcohol (PVA) content (2.84%), the ratio of drug to polymer (6.88) and the stirring rate (1007.59 rpm). The optimized responses for production yield and loading efficiency were found to be 68.86% and 55.90%, respectively, and the particle size were 23.27 ± 0.76 µm and the sorting coefficient (σ) was 0.732. Furthermore, in vitro release study suggested that microparticle could be a suitable delivery system in treating skin disease for its sustained release of drug. In conclusion, RSM can be successfully used to optimize the effect of formulation variables.

Adsorption properties of cellulose-derived hydrogel and magnetic hydrogels from Sophora flavescens on Cu2+ and Congo red.

This study synthesized a robust, magnetically responsive hydrogel from Sophora flavescens-modified cellulose and chitosan, employing Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA and DTG), and scanning electron microscopy (SEM) to confirm the preservation of cellulose's intrinsic properties and the hydrogel's remarkable elasticity, toughness, and porosity. These hydrogels integrate cellulose's structural backbone with functional moieties from chitosan, enhancing adsorption capabilities for Cu2+ ions and Congo red (CR) dye. Kinetic and thermodynamic analyses reveal that adsorption is spontaneous and endothermic, following a pseudo-second-order model and the Freundlich isotherm. Notably, Cu2+ adsorption capacity increases with pH, while CR adsorption initially decreases before rising, demonstrating the hydrogels' potential as effective, sustainable adsorbents for removing pollutants from water.