Preparation and characteristics of novel porous hydrogel films based on chitosan and glycerophosphate

Properties and biocompatibility of chitosan and silk fibroin blend films for application in skin tissue engineering

Chitosan/silk fibroin (CS/SF) blend films were prepared and evaluated for feasibility of using the films as biomaterial for skin tissue engineering application. Fourier transform infrared spectroscopy and differential scanning calorimetry analysis indicated chemical interaction between chitosan and fibroin. Chitosan enhanced β-sheet conformation of fibroin and resulted in shifting of thermal degradation of the films. Flexibility, swelling index, and enzyme degradation were also increased by the chitosan content of the blend films. Biocompatibility of the blend films was determined by cultivation with fibroblast cells. All films showed no cytotoxicity by XTT assay. Fibroblast cells spread on CS/SF films via dendritic extensions, and cell-cell interactions were noted. Cell proliferation on CS/SF films was also demonstrated, and their phenotype was examined by the expression of collagen type I gene. These results showed possibility of using the CS/SF films as a supporting material for further study on skin tissue engineering.

Chitosan-based nanoparticles as delivery systems of therapeutic proteins

Therapeutic proteins represent a significant part of the new pharmaceuticals coming on the market every year and are now widely spread in therapy to treat or relief symptoms related to many metabolic and oncologic diseases. The parenteral route remains as a primary strategy for protein administration essentially due to its specific physicochemical properties. However, the research on alternative nonparenteral delivery routes continues. The high molecular weight (MW), hydrophilicity, and charged nature of therapeutically valued proteins render transport through membranes very difficult. In this regard, chitosan arises as a promising candidate for the development of protein-containing drug formulations, due to its exceptional biological properties. Chitosan-based delivery systems have been proposed as valid approaches to provide protective conditions to proteins from denaturation and loss of activity, during preparation and delivery, as well as during long-term storage of the prepared formulation. In this chapter, one production method of a chitosan-based nanoparticle formulation is presented, as well as several characterization techniques to assess both nanoparticles and proteins characteristics and stability.

Physicochemical and biological activity study of genipin-crosslinked chitosan scaffolds prepared by using supercritical carbon dioxide for tissue engineering applications

The present study deals with the preparation of porous chitosan scaffolds by using a greener technique i.e., supercritical carbon dioxide (sc.CO2). 0.2 M chitosan (CS) solution in aqueous acetic acid was treated with 4% (w/v) genipin solution; the resulting hydrogels were subjected to solvent exchange prior to the final treatment procedures. Their morphology, pore structure, and physical properties were characterized by thermal analysis, X-ray diffractogram (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the specific surface areas and porosimetry of scaffolds were determined by using N2 adsorption. The biological activity of scaffolds was investigated by immersing them into 1.5 x simulated body fluid (SBF) and cellular attachment study was assessed using Alamar Blue assay by seeding MG63 osteoblastic cells onto the scaffolds. The sc.CO2 assisted chitosan scaffold prepared by using green chemistry approach is highly pure and bioactive and can be served as a potential material for tissue engineering applications.