engleski

Bio-inspired scaffolds based on silicon-wollastonite and multi-substituted hydroxyapatite-chitosan hydrogel

The scaffolds, which morphologically and physiologically mimic natural bone, are of high demand for regenerative medicine. To address this challenge, bioactive porous silicon/wollastonite (Si/W) scaffold was fabricated by additive manufacturing through the selective laser melting approach with a pore size of 400 μm, previously designed by using CAD. To increase biocompatibility and osteogenic properties of Si/W scaffolds, hydrogel based on multi-substituted hydroxyapatite (HAp) and biopolymer chitosan (CS/HAp) was incorporated into Si/W by impregnation and freezegelation method. HAp phase was obtained by wet precipitation method from biogenic source (cuttlefish bone) as a precursor of Ca2+ ions and was additionally substituted with 1.25 mol% of Sr2+, Mg2+, Zn2+ and SeO32- ions. The CS/HAp have shown a highly porous structure, with very well interconnected pores and homogeneously dispersed HAp, and high stability during 28 days in the degradation medium. Biological characterization in static and dynamic conditions by using human mesenchymal cells indicated that ionic substitutions have a beneficial effect on cells and tissues. SC/HAp have shown an increase in expression of osteogenesis-related markers, increased phosphate deposits and bone tissue formation. Therefore, SC/HAp was a good candidate to be incorporated in the Si/W scaffold to increase regenerative properties. The composite scaffolds were analysed by X-ray diffraction analysis, Fourier-transform infrared spectroscopy, scanning electron microscope, elemental mapping and compression test. By the combination of Si/W and CS/HAp, the biocompatibility of Si/W was enhanced, while the mechanical properties of SC/HAp were improved.

chitosan ; hydroxyapatite ; scaffold ; silicon ; substitution ; wollastonite

Pozvano predavanje održala Antonia Ressler.