chitosan and nanohydroxyapatite roles in physical and chemical characteristics of gelatin/chitosan/nanohydroxyapatite microspheres

the effects of chitosan/biopolymer (c/p) and nanohydroxyapatite/ biopolymer (nha/p) weight ratios on particle size and its uniformity, cross-linking density and nh2 content of nano-hydroxyapatite/chitosan/gelatin (nha/c/g) microspheres were investigated. microspheres were fabricated using water-in-oil emulsion. cross-linking of microspheres was performed using water soluble carbodiimide. particle size and its uniformity were evaluated using an optical microscope. the morphology of microspheres was studied by scanning electron microscopy. the obtained data from particle size measurements revealed that increments in c/p ratio increased the particle size while reducing its uniformity, and increased the nh2 content and cross linking density of the microspheres. it was shown that incremental increase in nha/p ratio increased the particle size and its uniformity and reduced the nh2 content and cross-linking density of the microspheres.morphological studies showed that the fabricated microspheres had spherical shape in medium level of c/p ratio and nha/p ratio. however, increasing in chitosan/biopolymer ratio induced some micro-cracks into the structure of microspheres.