Synthesis, characterization, and their some chemical and biological properties of PVA/PAA/nPS hydrogel nanocomposites: Hydrogel and wound dressing

The nanocomposite hydrogels were prepared by dispersing of the nanopomegranate seed particles into poly(vinyl alcohol)/poly(acrylic acid) blend matrix in an aqueous medium by the solvent casting method. These hydrogels were characterized using scanning electron microscopy, Fourier transform infrared spectra, differential scanning calorimetry, and optical contact angle instruments. The nanopomegranate seed, blend, and hydrogel nanocomposites were tested for microbial activity. In addition, cytocompatibilities of these blend and hydrogel nanocomposites/composites were tested on human lymphocyte with in vitro MTS cell viability assays. Fourier transform infrared spectra revealed that esterification reaction took place among functional groups in the structure of poly(vinyl alcohol) and poly(acrylic acid). The hydrophilic properties of all hydrogels decreased with increasing nanopomegranate seed content. The mean diameters of the nanopomegranate seed particles were about 88 nm. Nanopomegranate seed particles demonstrated antibacterial properties against gram-positive bacteria, Staphylococcus aureus, and gram-negative bacteria, Escherichia coli. The lymphocyte viabilities increased after addition of nanopomegranate seeds into the polymer blend. The swelling behavior of blend and hydrogels was dependent on the cross-linking density created by the reaction between poly(vinyl alcohol)/poly(acrylic acid) blend and nanopomegranate seed. Scanning electron microscopy images were highly consistent with Fourier transform infrared spectra, differential scanning calorimetry, and antibacterial activity results.

Chitosan-sodium Alginate Nanoparticle as a Promising Approach for Oral Delivery of Rosuvastatin Calcium: Formulation, Optimization and In vitro Characterization

Rosuvastatin calcium is the most effective antilipidemic drug and is called "super-statin" but it exhibits low aqueous solubility and poor oral bioavailability of about 20%. The present work aimed to develop and optimize chitosan-alginate nanoparticulate formulation of rosuvastatin which can improve its solubility, dissolution and therapeutic efficacy. Chitosan-alginate nanoparticles were prepared by ionotropic pre-gelation of an alginate core followed by chitosan polyelectrolyte complexation and optimization was done in terms of two biopolymers, crosslinker concentrations. The chitosan-alginate nanoparticles were characterized by various techniques such as particle properties such as size; size distribution (polydispersity index); Zeta-potential measurements and Fourier transform infrared spectra respectively. The designed rosuvastatin loaded chitosan-alginate nanoparticle had the average particle size of 349.3 nm with the zeta potential of +29.1 mV, and had high drug loading and entrapment efficiencies. Fourier transform infrared spectra showed no chemical interaction between the rosuvastatin and chitosan-alginate nanoparticle upon the encapsulation of rosuvastatin within the nanoparticles. Nanoparticles revealed a fast release during the first two hours followed by a more gradual drug release during a 24 h period. Hence, our studies demonstrated that the new chitosan-alginate nanoparticle system of rosuvastatin is a promising strategy for improving solubility and in turn, the therapeutic efficacy of rosuvastatin. Therefore, the rosuvastatin-loaded chitosan-alginate nanoparticles are a promising approach for the oral delivery of rosuvastatin.