title: Pullulan-based composite scaffolds for bone tissue engineering: Improved osteoconductivity by pore wall mineralization.
abstract: Porous hydrogels have been explored for bone tissue engineering; however their poor mechanical properties make them less suitable as bone graft substitutes. Since incorporation of fillers is a well-accepted method for improving mechanical properties of hydrogels, in this work pullulan hydrogels were reinforced with nano-crystalline hydroxyapatite (nHAp) (5 wt% nHAp in hydrogel) and poly(3-hydroxybutyrate) (PHB) fibers (3 wt% fibers in hydrogel) containing nHAp (3 wt% nHAp in fibers). Addition of these fillers to pullulan hydrogel improved compressive modulus of the scaffold by 10 fold. However, the hydrophilicity of pullulan did not support adhesion and spreading of cells. To overcome this limitation, porous composite scaffolds were modified using a double diffusion method that enabled deposition of hydroxyapatite on pore walls. This method resulted in rapid and uniform coating of HAp throughout the three-dimensional scaffolds which not only rendered them osteoconductive in vitro but also led to an improvement in their compressive modulus. These results demonstrate the potential of mineralized pullulan-based composite scaffolds in non-load bearing bone tissue engineering.
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology-Kanpur, Kanpur, 208016, India.
authors.lastname: Amrita
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology-Kanpur, Kanpur, 208016, India.
authors.forename: Aditya
authors.initials: A
authors.lastname: Arora
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology-Kanpur, Kanpur, 208016, India.
authors.forename: Poonam
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology-Kanpur, Kanpur, 208016, India. Electronic address: dsk@iitk.ac.in.
authors.forename: Dhirendra S
authors.initials: DS
authors.lastname: Katti
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D018786:Bone Substitutes / Q000737:chemistry; D001842:Bone and Bones / Q000502:physiology*; D002448:Cell Adhesion; D002460:Cell Line; D019245:Compressive Strength; D017886:Durapatite / Q000737:chemistry; D005936:Glucans / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D006885:Hydroxybutyrates / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry; D016062:Porosity; D000091402:Prohibitins; D023822:Tissue Engineering; D054457:Tissue Scaffolds; D000094122:Polyhydroxybutyrates
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D017886:Durapatite; D005936:Glucans; D020100:Hydrogels; D006885:Hydroxybutyrates; D011091:Polyesters; D000091402:Prohibitins; C000717328:PHB protein, human; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates; C009109:pullulan
keywords: Bone tissue engineering; Composite; Hydrogel; Hydroxyapatite; Pore surface mineralization; Pullulan