The formation of hydroxyapatite is important for artificial materials to show high biological affinities for bone tissue. The present study focused on the synthesis of hydrogels capable of showing apatite formation, through modification of polyglutamic acid (PGA) with 3-aminopropyltriethoxysilane (APTES), followed by treatment with calcium chloride solution. A transparent bulk hydrogel was obtained at a molar ratio of PGA/APTES of 0.5. Prior soaking of the PGA hydrogel in calcium chloride solution accelerated the formation of bone-like apatite in a simulated body fluid. The modified PGA hydrogel is a candidate material for a biodegradable scaffold for bone regeneration.
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