title: On-Demand Guided Bone Regeneration with Microbial Protection of Ornamented SPU Scaffold with Bismuth-Doped Single Crystalline Hydroxyapatite: Augmentation and Cartilage Formation.
abstract: Guided bone regeneration (GBR) scaffolds are futile in many clinical applications due to infection problems. In this work, we fabricated GBR with an anti-infective scaffold by ornamenting 2D single crystalline bismuth-doped nanohydroxyapatite (Bi-nHA) rods onto segmented polyurethane (SPU). Bi-nHA with high aspect ratio was prepared without any templates. Subsequently, it was introduced into an unprecedented synthesized SPU matrix based on dual soft segments (PCL-b-PDMS) of poly(ε-caprolactone) (PCL) and poly(dimethylsiloxane) (PDMS), by an in situ technique followed by electrospinning to fabricate scaffolds. For comparison, undoped pristine nHA rods were also ornamented into it. The enzymatic ring-opening polymerization technique was adapted to synthesize soft segments of PCL-b-PDMS copolymers of SPU. Structure elucidation of the synthesized polymers is done by nuclear magnetic resonance spectroscopy. Sparingly, Bi-nHA ornamented scaffolds exhibit tremendous improvement (155%) in the mechanical properties with excellent antimicrobial activity against various human pathogens. After confirmation of high osteoconductivity, improved biodegradation, and excellent biocompatibility against osteoblast cells (in vitro), the scaffolds were implanted in rabbits by subcutaneous and intraosseous (tibial) sites. Various histological sections reveal the signatures of early cartilage formation, endochondral ossification, and rapid bone healing at 4 weeks of the critical defects filled with ornamented scaffold compared to SPU scaffold. This implies osteogenic potential and ability to provide an adequate biomimetic microenvironment for mineralization for GBR of the scaffolds. Organ toxicity studies further confirm that no tissue architecture abnormalities were observed in hepatic, cardiac, and renal tissue sections. This finding manifests the feasibility of fabricating a mechanically adequate nanofibrous SPU scaffold by a biomimetic strategy and the advantages of Bi-nHA ornamentation in promoting osteoblast phenotype progression with microbial protection (on-demand) for GBR applications.
authors.affiliation: Indian Institute of Technology , Rubber Technology Centre, Kharagpur 721302, India.
authors.forename: M
authors.initials: M
authors.lastname: Selvakumar
authors.affiliation: Sanjay Gandhi Post Graduate Institute of Medical Science , Department of Medical Genetics, Lucknow 226014, Uttar Pradesh India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Srivastava
authors.affiliation: Indian Institute of Technology , School of Medical Science and Technology, Kharagpur 721302, India.
authors.forename: Harpreet Singh
authors.initials: HS
authors.lastname: Pawar
authors.affiliation: Indian Institute of Technology , School of Medical Science and Technology, Kharagpur 721302, India.
authors.forename: Nimmy K
authors.initials: NK
authors.lastname: Francis
authors.affiliation: Indian Institute of Technology , School of Medical Science and Technology, Kharagpur 721302, India.
authors.forename: Bodhisatwa
authors.initials: B
authors.lastname: Das
authors.affiliation: Bharathidasan University , Department of Biotechnology and Genetic Engineering, Tiruchirappalli 620024, Tamilnadu India.
authors.forename: G
authors.initials: G
authors.lastname: Sathishkumar
authors.affiliation: Indian Institute of Technology , RISUG® and Allied Science Laboratories, School of Medical Science and Technology, Kharagpur 721302, India.
authors.forename: Bhuvaneshwaran
authors.initials: B
authors.lastname: Subramanian
authors.affiliation: Universiti Teknologi Malaysia , Faculty of Bioscience and Medical Engineering, IJN-UTM Cardiovascular Engineering Centre, Johor Bahru 81310, Malaysia.
authors.forename: Saravana Kumar
authors.initials: SK
authors.lastname: Jaganathan
authors.affiliation: National Institute of Technology Karnataka , Department of Metallurgical and Materials Engineering, Mangalore 575025, Karnataka India.
authors.forename: Gibin
authors.initials: G
authors.lastname: George
authors.affiliation: National Institute of Technology Karnataka , Department of Metallurgical and Materials Engineering, Mangalore 575025, Karnataka India.
authors.forename: S
authors.initials: S
authors.lastname: Anandhan
authors.affiliation: Indian Institute of Technology , School of Medical Science and Technology, Kharagpur 721302, India.
authors.forename: Santanu
authors.initials: S
authors.lastname: Dhara
authors.affiliation: Indian Institute of Technology , Rubber Technology Centre, Kharagpur 721302, India.
authors.forename: Golok B
authors.initials: GB
authors.lastname: Nando
authors.affiliation: Indian Institute of Technology , Rubber Technology Centre, Kharagpur 721302, India.
authors.forename: Santanu
authors.initials: S
authors.lastname: Chattopadhyay
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D001424:Bacterial Infections / Q000188:drug therapy*; D001729:Bismuth / Q000737:chemistry / Q000494:pharmacology; D001861:Bone Regeneration / Q000187:drug effects*; D020219:Chondrogenesis / Q000187:drug effects*; D004129:Dimethylpolysiloxanes / Q000737:chemistry / Q000494:pharmacology; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008297:Male; D011091:Polyesters / Q000737:chemistry / Q000494:pharmacology; D011817:Rabbits; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D004129:Dimethylpolysiloxanes; D011091:Polyesters; C016240:polycaprolactone; C013830:baysilon; D017886:Durapatite; D001729:Bismuth
keywords: electrospun scaffold; guided bone regeneration; histology; nanohydroxyapatite; segmented polyurethane