Dynamic chitosan-based hydrogels with enhanced antioxidant activity were synthesized through the formation of reversible imine linkages with 5-methoxy-salicylaldehyde. These hydrogels exhibited a porous structure and swelling capacity, influenced by the crosslinking degree, as confirmed by SEM and POM analysis. The dynamic nature of the imine bonds was characterized through NMR, swelling studies in various media, and aldehyde release measurements.
View Article and Find Full Text PDFPlasma-activated chitosan (PAC) colloids for cancer treatment were obtained by using the cold atmospheric plasma technique. Chitosan solutions were irradiated by plasma ignited in argon gas and in a mixture of argon with nitrogen and oxygen gases in certain ratios. The structural modifications of chitosan and the chemical species generated in plasma were investigated by EPR, LC-MS/MS, XRD, DLS, and TGA methods.
View Article and Find Full Text PDFIn recent years, multidrug-resistant bacteria have developed the ability to resist multiple antibiotics, limiting the available options for effective treatment. Raising awareness and providing education on the appropriate use of antibiotics, as well as improving infection control measures in healthcare facilities, are crucial steps to address the healthcare crisis. Further, innovative approaches must be adopted to develop novel drug delivery systems using polymeric matrices as carriers and support to efficiently combat such multidrug-resistant bacteria and thus promote wound healing.
View Article and Find Full Text PDFThis paper presents an alternative for enhancing the durability of poly (L-lactide) (PLLA) by racemic nucleation following stereo-complexation with a selected poly (D-lactide) (PLDA). The compounds are obtained by melt blending of a PLLA grade, previously designed for 3D printing but with a low heat deflection temperature and impact resistance, with grades of PLDA differing in their molecular weight (Mw), D-lactide content (DS) and concentration. Our method considered how to reveal the racemic nucleation caused by stereo-complexation and its influence on functional properties.
View Article and Find Full Text PDFInterest in renewable polymers increased exponentially in the last decade and in this context poly(lactic acid) (PLA) became the leader mainly for practical reasons. Nevertheless, it is outstanding also from a scientific point of view, because its thermal and morphological properties are offering challenging new insights. With regard to dynamic mechanical analysis (DMA), PLA does not have the classical behavior of a thermoplastic polymer.
View Article and Find Full Text PDFThe paper reports a new mathematical model for understanding the mechanism delivery from drug release systems. To do this, two drug release systems based on chitosan and diclofenac sodium salt as a drug model, were prepared by in situ hydrogelation in the presence of salicylaldehyde. The morphology of the systems was analyzed by scanning electron microscopy and polarized light microscopy and the drug release was investigated into a medium mimicking the environment.
View Article and Find Full Text PDFThis paper reports the calibration of a theoretical multifractal model based on empirical data on the urea release from a series of soil conditioner systems. To do this, a series of formulations was prepared by in situ hydrogelation of chitosan with salicylaldehyde in the presence of different urea amounts. The formulations were morphologically characterized by scanning electron microscopy and polarized light microscopy.
View Article and Find Full Text PDFThe paper reports new soil conditioner systems obtained by in situ hydrogelation of chitosan with salicylaldehyde in the presence of urea fertilizer, designed to address both fertilization and water retention of the soil. The new systems were structural, supramolecular and morphological characterized by FTIR spectroscopy, XRD diffraction, POM and SEM microscopy. The rate of urea release has been investigated by NMR analysis and the release mechanism has been assessed by fitting five mathematical models.
View Article and Find Full Text PDFUltrason Sonochem
July 2018
A series of chiral hydrogels was prepared from a homogeneous mixture of chitosan and betulinic aldehyde in different molar ratios, under the effect of ultrasound. The hydrogelation mechanism has been investigated by FTIR and CD spectroscopy, wide angle X-ray diffraction and polarized light microscopy. The morphology of hydrogels was examined by SEM.
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