Preparation and Characterization of Nano-Biomaterial Dressings for Skin Burn Treatment

Abstract

Abstract This work aims to study the interaction between the cellulose biopolymer and chitosan-propolis nanoparticles (Cs/PrPNPs) to understand the mechanism of their interaction as well as make use of our understanding to prepare cellulose/chitosan-propolis nanofiber. The work during this thesis is divided into two main parts: theoretical part and experimental one. The theoretical part includes the usage of molecular modeling concepts and methods for building up model molecules of our entities to optimize them then validate their interaction probability together through the resultant and calculated electronic and quantitative structure analysis relationship (QSAR) properties. The experimental part is carried out to prove the constructed theoretical model and make sure from being possible to be obtained in labs as a first step for having a prototype model to be applied on a large scale in the coming soon future. Optimizing the individual structures of cellulose biopolymer and chitosan-propolis nanoparticles (Cs/PrPNPs) and their interaction probabilities are carried out at high DFT theoretical level. Depending on the results of the total energy, total dipole moment and HOMO/LUMO band gap energies we get that interaction of chitosan with hexamethoxy flavone NPs is through its NH and cellulose through OH of chitosan indicated the more reactive to be interacted with biological tissues. According to QSAR, interaction of Cs-hexamethoxy flavone NPs is more hydrophilic (soluble) and when it interacts with cellulose its solubility decreased which will be confirmed by experimental work. In experimental part Chitosan/propolis nanoparticles were prepared by ion gelation method with size ranging from 150 to 200 nm and a polydispersity index of 0.3. Chitosan/propolis nanoparticles were preloaded in the CA solution to ensure homogeneity. Cellulose acetate nanofibers were deacetylated by NaOH after optimizing the reaction time and the concentration of NaOH solution, and the product was confirmed with FTIR analysis. Loaded deacetylated cellulose nanofibers have shown the greatest hydrophobicity measured by contact angle (which is ensured from electronic and QSAR properties measured in theoretical part) and amount of drug release from this fiber was about 55% within 10 days. Cytotoxicity of propolis and chitosan/propolis nanoparticles were tested and the experimental IC50 value was about 137.5 and 116.0 µg/mL, respectively, with p-value ≤ 0.001. In addition, chitosan/propolis nanoparticles loaded into cellulose nanofibers showed a cell viability of 89.46%. In-vivo experiments showed that after 21 days of treatment with the loaded nanofibers repairing of epithelial cells, hair follicles and sebaceous glands in the skin of the burn wound burn in a mice model. So, from theoretical, experimental results and due to the acceptable safety of the natural materials used, the suggested wound dressing can be applied to human burns.