Fabrication And Characterization Of Collagen-P3/4HB TEHV Nonwoven Composite Scaffolds

PartⅠFabrication of P3/4HB Nonwoven Scaffolds and Effects on the Behavior of MyofibroblastsObjective: To fabricate P3/4HB nonwoven scaffolds by electrospinning and investigate the effects of fiber diameter and pore size on myofibroblasts cultured on electrospun scaffolds in vitro.Methods: P3/4HB nonwoven scaffolds with different fiber diameters and pore sizes were fabricated by electrospinning, and then seeded by myofibroblasts harvested from rats. After 1 week's cultivation, SEM was performed, cell count and MTT test were used to examine cell attachment and proliferation respectively.Results: Myofibroblasts were adhered well and proliferated on the microfiber scaffold (1.24μm in diameter) ,whereas reduced cell adhesion on the sub-microfiber scaffold (0.58μm in diameter) and poor cell spreading on microfiber scaffold (2.79μm in diameter,)were observed.Conclusions: Fiber diameter,pore size have influence on cell adhesion ,proliferation and various other cell behaviors. Microfiber electrospun scaffold is an optimal 3D matrix for myofibroblast.PartⅡOxygen Plasma Surface Modification of P3/4HB Scaffolds and Effects on the Adhesion of MyofibroblastsObjective: To investigate the effects of oxygen plasma surface modification on electrospun P3/4HB nonwoven scaffolds.Methods: Electrospun P3/4HB nonwoven scaffolds were modified by low pressure oxygen plasma and physicochemical characteristics of the modified surfaces were investigated by x-ray photoelectron spectrometer, contact angle measurements together with maximum stress measurements, the cell adhesion capability tests on modified scaffolds and serum preconditioned scaffolds were carried out using myofibroblasts harvested from rats. Results :XPS show the increase in the oxygen content,(C-OH)group and COOR(COOH)group of P3/4HB scaffolds after oxygen plasma surface modification,water contact angle decreased, myofibroblasts attachment were improved ,whereas the maximum stress unchanged.Conclusions: Hydrophilic functional groups such as carboxy group and hydroxyl group can be generated on the surface of P3/4HB nonwoven scaffolds by using oxygen plasma surface modification, which implied its tremendous potential use in tissue engineering field.PartⅢImmobilization of TypeⅠCollagen on P3/4HB Electrospun ScaffoldsObjective: To fabricate and characterize collagen-anchored P3/4HB composite scaffolds.Methods: Electrospun P3/4HB nonwoven scaffolds were modified by low pressure oxygen plasma treatment, then they were collagen immobilized using the coupling reaction. Physicochemical characteristics of the modified surfaces were investigated by x-ray photoelectron spectrometer (XPS) and the ninhydrin method , the cell proliferation behavior on surface-modified scaffolds were analyzed using myofibroblasts harvested from rats.Results: XPS spectra confirmed that typeⅠcollagen was immobilized onto the surface of P3/4HB nonwoven scaffolds successfully and the proliferation abilities of myofibroblasts cultured on the modified scaffolds were significantly improved. Conclusions: It's an effective method to fabricate collagen-anchored P3/4HB nonwoven scaffolds by immobilizing typeⅠcollagen onto the surface of P3/4HB, which implied its tremendous potential use in tissue engineering field.