title: Preparation and biological properties of PLLA/beta-TCP composites reinforced by chitosan fibers.
abstract: Chitosan fibers were introduced into a poly(L-lactic acid)/beta-tricalcium phosphate (PLLA/beta-TCP) matrix as reinforcement to prepare scaffold materials for bone tissue engineering with adequate initial strength and a feasible degradation rate. The structure and morphology of the composites were observed by a scanning electron microscope (SEM). The porosity of the composites was tested by Archimedes' method. The mechanical property of the composites was measured. Simulated body fluid (SBF) experiments were conducted to assess the bioactivity of the composites. The chemical components of resultants on surfaces were analyzed by Fourier transform infrared spectroscopy (FTIR). The influence of the addition of chitosan fibers on the pH value, mass loss rate and structure of samples during immersion was also discussed. The results show that the initial compressive strength reaches 16.07 MPa when the composites prepared have a porosity of 36%. With the degradation of chitosan fibers, an interconnected structure is earlier formed in situ throughout the scaffolds, which is favorable for new bone ingrowth. The compressive strength of the composite decreases flatly and still maintains at 5.28 MPa after immersion in SBF for 24 days. Meanwhile, the formation of a layer of bone-like apatites on the surfaces of the samples indicates good biological activity. It is concluded that the composites have a promising prospect as bone tissue engineering materials.
authors.affiliation: School of Materials Science and Engineering, Harbin Institute of Technology, Heilongjiang Province, 150001, People's Republic of China. jmsdxwangjing@163.com
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Lijie
authors.initials: L
authors.lastname: Qu
authors.forename: Xiangcai
authors.initials: X
authors.lastname: Meng
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.forename: Hongbo
authors.initials: H
authors.lastname: Li
authors.forename: Guangwu
authors.initials: G
authors.lastname: Wen
mesh_terms: D001826:Body Fluids / Q000737:chemistry*; D018786:Bone Substitutes / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D019245:Compressive Strength; D004548:Elasticity; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; C485817:beta-tricalcium phosphate; D019344:Lactic Acid; C033616:poly(lactide); D048271:Chitosan