Biocompatible Scaffolds from Chitosan/Cellulose Acetate & Blends therefrom [ READ ]
Nouran A. Milad, Mona M. Naim, Mahmoud M. Elewa, Mervat A. Abdelkawi
Tissue engineering is a very important field in biomedical applications such as in skin regeneration, nerves, liver, cartilage, heart valves, etc., of which the essential requirements are to prepare suitable scaffolds that are biocompatible, biodegradable and of uniform pore-size. Natural biocompatible polymers such as chitosan (CS) have been often explored in the preparation of scaffolds, that are later seeded with cells, in bioreactors, for replacing burnt or damaged skin. In addition, regenerated cellulose, such as cuprophane, has been the membrane of choice for blood purification by the artificial kidney, for decades. Accordingly, in this work scaffolds were fabricated from either CS or cellulose acetate (CA), or blends therefrom, by a simple novel laboratory technique, in which the polymer/polymer blend is dissolved in a suitable solvent/solvent mixture, to form solutions which are cast by a special casting assembly into membranes, such that pores and scaffolds are created, by forcing humid air to flow along the as-cast membrane. CS was prepared from shrimp shells through deacetylation with concentrated sodium hydroxide (NaOH) solution. Variables investigated were: type of polymer, type of solvent, initial polymer solution concentration, concentration of deacetylation solution, and time of exposure to humid air flow of as-cast membrane. Scanning Electron Microscopy (SEM) examinations were conducted to determine membrane surface and cross-section morphologies, and it was found that CS gave a suitable surface and that the blend membrane gave a better membrane as regards the number of pores, while CA gave promising scaffolds. Moreover, the type of solvent affected the membrane morphology, and deacetylation with 50% NaOH solution gave a more uniform CS membrane than lower concentration. Moreover, it was shown that a 30 min exposure time gave a membrane with more scaffolds/pores >20 min >10 min. The scaffolds suggest that they might be suitable for formation of replacement skin tissue, after cell seeding, in future work, which is currently proceeding in our lab.
Nouran A. Milad, Mona M. Naim, Mahmoud M. Elewa, Mervat A. Abdelkawi
Tissue engineering is a very important field in biomedical applications such as in skin regeneration, nerves, liver, cartilage, heart valves, etc., of which the essential requirements are to prepare suitable scaffolds that are biocompatible, biodegradable and of uniform pore-size. Natural biocompatible polymers such as chitosan (CS) have been often explored in the preparation of scaffolds, that are later seeded with cells, in bioreactors, for replacing burnt or damaged skin. In addition, regenerated cellulose, such as cuprophane, has been the membrane of choice for blood purification by the artificial kidney, for decades. Accordingly, in this work scaffolds were fabricated from either CS or cellulose acetate (CA), or blends therefrom, by a simple novel laboratory technique, in which the polymer/polymer blend is dissolved in a suitable solvent/solvent mixture, to form solutions which are cast by a special casting assembly into membranes, such that pores and scaffolds are created, by forcing humid air to flow along the as-cast membrane. CS was prepared from shrimp shells through deacetylation with concentrated sodium hydroxide (NaOH) solution. Variables investigated were: type of polymer, type of solvent, initial polymer solution concentration, concentration of deacetylation solution, and time of exposure to humid air flow of as-cast membrane. Scanning Electron Microscopy (SEM) examinations were conducted to determine membrane surface and cross-section morphologies, and it was found that CS gave a suitable surface and that the blend membrane gave a better membrane as regards the number of pores, while CA gave promising scaffolds. Moreover, the type of solvent affected the membrane morphology, and deacetylation with 50% NaOH solution gave a more uniform CS membrane than lower concentration. Moreover, it was shown that a 30 min exposure time gave a membrane with more scaffolds/pores >20 min >10 min. The scaffolds suggest that they might be suitable for formation of replacement skin tissue, after cell seeding, in future work, which is currently proceeding in our lab.
