Collagen - Preparation And Properties Of Nanocrystalline Cellulose Composites

Collagen matrix has been widely used in the field of biomedical engineering. However, the poormechanical properties of collagen have limited its application. Here, rod-like cellulosenanocrystals (CNCs) were fabricated and used to reinforce collagen matrix. A series ofcollagen/CNCs films and three-dimensional scaffolds were prepared by collagen solution withCNCs suspensions homogeneously dispersed at CNCs: collagen weight ratios of1,3,5,7and10.The morphology of the resulting samples was analyzed by scanning electron microscopy (SEM),the enhancement of the thermomechanical properties of the collagen/CNCs composites weredemonstrated by thermal gravimetric analysis (TGA) and mechanical testing. In addition, in vitrocell culture studies revealed that the CNCs have no negative effect on the cell morphology,viability, and proliferation and possess good biocompatibility.Gelatin is a biodegradable polymer derived from collagen, contained a number of functionalgroups. Because of the biosafety of gelatin has been proven through and its low cost, so it hasbeen extensively applied for pharmaceutical and medical applications. Other advantages ofgelatin include the flexibility in processing and easiness of chemical modification. In this regard,gelatin microspherical as carriers in drug delivery was successfully synthesized and employed.The biodegradable gelatin microspheres were prepared and used as storage and controlledrelease of bFGF or Vancomycin. The complex microspheres mixed with collagen/CNCsscaffolds to form complex scaffolds. The objectives are to examine faster rate of angiogenesisand antimicrobial activities of the complex scaffolds, to investigate the incorporation of bFGF orVancomycin into the microspheres and its release profile and to characterize the gelatinmicrospheres and collagen/CNCs scaffolds. Among the CNCs contents used, a loading of5wt%led to the maximum mechanical properties for the collagen/CNCs composite scaffolds. And inthis work we used a rate model to implanted scaffolds in rats and to evaluate the function of thewound dressing.We conclude that the incorporation of CNCs is a simple and promising way to reinforce collagen matrix without impairing biocompatibility. This study demonstrates that the composites showgood potential for use in the field of skin tissue engineering.