Fabrication of scaffolds made of gelatin and calcium phosphate for tissue regeneration

Abstract

The objective of this work was to fabricate gelatin and alpha-tricalcium phosphate (α-TCP) scaffolds via freeze-drying technique. Both materials are well known to be promising candidates for tissue engineering and drug delivery applications. One of the main characteristics that we look for in scaffolds and drug delivery systems is the formation of an adequate porosity. The role of this porosity is to ensure cell colonisation, flow transport of nutrients and metabolic waste in scaffolds for tissue engineering and to enhance the loading capacity and delivery rate in delivery systems. Two types of scaffolds were produced: one of organic matrix reinforced by an inorganic phase (α-TCP) and the other of inorganic matrix (α-TCP) with gelatin as a binder. Organic phase plays an important role in the toughness of bone whereas inorganic phase enhances its mechanical properties. The aim was to produce scaffolds with organic matrix and enhance the existing process, and also create new scaffolds with inorganic matrix. Different strategies were tested in order to optimize the fabrication process of the scaffolds. Characterization of the scaffolds included: microstructural evaluation by scanning electron microscopy, evaluation of the percentage of isolated porosity by helium pycnometry, rigidity test by mechanical testing and the study of the proportion of phases in the scaffold by X-ray diffraction analysis. The structure network has been improved in the case of scaffolds with organic matrix, by decreasing the content of closed pores and also by ensuring total incorporation of the α-TCP powder in the scaffold. Regarding the creation of scaffolds of inorganic matrix, the results, in terms of porosity and mechanical properties, were very promising and opened a new area of investigation.