Application of Chitosan-Based Biomaterials in Tissue Engineering - Chitosan Based Hydrogels: Functions and Applications - page 409

Figure 9.7
EM micrographs of chitosan particles obtained by the precipitation method (a); pore morphology in the
chitosan scaffolds (b); cross section of chitosan scaffolds obtained by the particle aggregation method (c); and
the interface between the chitosan particles after the production of the scaffolds (d). (From Malafaya, P. B. et al
2005. J Mater Sci: Mater Med 16: 1077-1085. With permission.)
their contact points to form the microsphere chitosan porous scaffold ( cf. Figure 9.7) [31].
The average pore diameter was 265.46 ± 24.27 μm. Porosity and interconnectivity of
the chitosan microsphere scaffold is 27.78 ± 2.80% and 94.99 ± 1.41%, respectively. It is
important to stress that interconnectivity was calculated with a limit in pore size of
53 μm as the minimum value for interconnected pores, meaning that interconnection
diameters lower than this value were considered as closed pores [32]. A higher sintering
temperature resulted in decreased porosity, because greater fusion between microspheres
can occur when sintering temperature is elevated. Moreover, a higher sintering tempera-
ture and a longer sintering time have equivalent effects on the fabrication of microsphere
scaffolds [7,33].
9.3 Interactions between Chitosan-Based Biomaterials and Cells
With the development of biology and genetic engineering, the design idea of chitosan-
based biomaterials is gradually clear. It should be able to control the interactions between
cell and materials and further control cell behaviors, such as attachment, proliferation,
differentiation, and apoptosis, which is the foundation research for the application of
chitosan-based biomaterials in tissue engineering. Therefore, it is necessary to understand
the interactions between cells and chitosan-based biomaterials and their influencing