title: Biomimetic, bioactive etheric polyphosphazene-poly(lactide-co-glycolide) blends for bone tissue engineering.
abstract: The long-term goal of this work is to develop biomimetic polymer-based systems for bone regeneration that both allow for neutral pH degradation products and have the ability to nucleate bonelike apatite. In this study, the etheric biodegradable polyphosphazene, poly[(50%ethyl glycinato)(50%methoxyethoxyethoxy)phosphazene] (PNEG(50)MEEP(50)) was blended with poly(lactide-co-glycolide) PLAGA and studied their ability to produce high-strength degradable biomaterials with bioactivity. Accordingly, two blends with weight ratios of PNEG(50)MEEP(50) to PLAGA 25:75 (BLEND25) and 50:50 (BLEND50) were fabricated using a mutual solvent approach. Increases in PNEG(50)MEEP(50) content in the blend system resulted in decreased elastic modulus of 779 MPa when compared with 1684 MPa (PLAGA) as well as tensile strength 7.9 MPa when compared with 25.7 MPa (PLAGA). However, the higher PNEG(50)MEEP(50) content in the blend system resulted in higher Ca/P atomic ratio of the apatite layer 1.35 (BLEND50) when compared with 0.69 (BLEND25) indicating improved biomimicry. Furthermore, these blends supported primary rat osteoblast adhesion and proliferation with an enhanced phenotypic expression when compared with PLAGA. These findings establish the suitability of PNEG(50)MEEP(50)-PLAGA biodegradable blends as promising bioactive materials for orthopedic applications.
authors.affiliation: Department of Orthopaedic Surgery, University of Connecticut, Farmington, Connecticut 06030, USA.
authors.forename: Meng
authors.initials: M
authors.lastname: Deng
authors.forename: Lakshmi S
authors.initials: LS
authors.lastname: Nair
authors.forename: Syam P
authors.initials: SP
authors.lastname: Nukavarapu
authors.forename: Sangamesh G
authors.initials: SG
authors.lastname: Kumbar
authors.forename: Justin L
authors.initials: JL
authors.lastname: Brown
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Krogman
authors.forename: Arlin L
authors.initials: AL
authors.lastname: Weikel
authors.forename: Harry R
authors.initials: HR
authors.lastname: Allcock
authors.forename: Cato T
authors.initials: CT
authors.lastname: Laurencin
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001031:Apatites / Q000494:pharmacology; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology*; D001842:Bone and Bones / Q000187:drug effects* / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002478:Cells, Cultured; D004987:Ethers / Q000737:chemistry / Q000494:pharmacology*; D008422:Materials Testing; D055595:Mechanical Phenomena / Q000187:drug effects; D009943:Organophosphorus Compounds / Q000737:chemistry / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D011098:Polyglactin 910 / Q000737:chemistry / Q000494:pharmacology*; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering; D044366:Transition Temperature / Q000187:drug effects
chemical_list: D001031:Apatites; D001672:Biocompatible Materials; D004987:Ethers; D009943:Organophosphorus Compounds; D011108:Polymers; C108974:poly(phosphazene); D011098:Polyglactin 910; D000469:Alkaline Phosphatase