Hydroxyapatite Scaffolds Produced from Cuttlefish Bone via Hydrothermal Transformation for Application in Tissue Engineering and Drug Delivery Systems

Abstract

An increase in life expectancy due to improvements in healthcare, in parallel with high percentage of injures, because of traffic accidents and sport activities, has emerged as the primary reasons for the replacements of lost, infected, and damaged bones. Combined with tissue engineering, this is an area of great interest to regenerative medicine. Novel scaffolds development, providing a suitable environment that can favor osteoinduction for the newly formed bone is needed. Composite porous hydrogels, based on alginate and chitosan with the dispersed phase from powders of bioceramics, such as hydroxyapatite (HAp), are recently developed for this reason. This work presents a reverse and novel approach, where these two popular hydrogels are infiltrated in a 3D HAp-scaffold. More specifically, HAp is obtained from aragonite from cuttlefish bone via hydrothermal transformation. This reinforcement of HAp with alginate or chitosan hydrogels, through infiltration method gives to the final product proper mechanical potential for hard tissue regeneration. The structure of the produced scaffolds resembles the microstructure and the texture of the natural bone. These advanced scaffolds are easily handled by the surgeon while maintaining their porous structure during the implantation process to promote the regeneration of newly formed bone tissue. In particular, once such a scaffold is implanted in an area where the bone tissue is lost, biological liquids will be able to penetrate into the pores of the lyophilized composite scaffold. The polymeric matrix will then be dissolved and the remaining HAp, or its precursor compounds, which will eventually transform into HAp, will promote osteoinduction. The worldwide availability and the low cost of cuttlefish bone, along with their biological-natural origin are attractive features making them highly sorted material used in the preparation of advanced scaffolds containing HAp for applications in biomedicine. The optimization of the fabrication technique is required to unravel the endless potential of biomaterials, shedding light on this promising interdisciplinary field, which includes both tissue engineering and drug delivery system approaches.