Pengaruh penambahan graphite, graphene oxide, dan carbon nanotube terhadap karakteristik fisikokimia perancah chitosan/hyaluronic acid/hydroxyapatite untuk aplikasi rekayasa jaringan = Effect of graphite, graphene oxide, and carbon nanotubes on the physicochemical characteristics of chitosan/hyaluronic acid/hydroxyapatite scaffolds for tissue engineering applications