Surface modification of interconnected porous scaffolds

Abstract

Surface properties of scaffolds play an important role in cell adhesion and growth. Biodegradable poly(alpha-hydroxy acids) have been widely used as scaffolding materials for tissue engineering; however, the lack of functional groups is a limitation. In this work, gelatin was successfully immobilized onto the surface of poly(alpha-hydroxy acids) films and porous scaffolds by a new entrapment process. The surface composition and properties were examined using attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectra (XPS), and contact angle measurements. Control over the amount of entrapped gelatin was achieved by varying the solvent composition, the duration of soaking, the concentration of gelatin in solution, and chemical crosslinking. The amount of entrapped gelatin increased with the ratio of dioxane/water in the solvent mixture used. Chemical crosslinking after physical entrapment considerably increased the amount of retained gelatin on the surface of poly(alpha-hydroxy acids). Osteoblasts were cultured on these films and scaffolds. The surface modification significantly improved cell attachment and proliferation. Cell numbers on the surface-modified films and scaffolds were significantly higher than those on controls 4 h and 1 day after cell seeding. The osteoblasts showed higher proliferation on surface-modified scaffolds than on the control during 4 weeks of in vitro cultivation. More collagen fibers and other cell secretions were deposited on the surface-modified scaffolds than on the control scaffolds. This novel surface treatment strategy provides a convenient and universal way to modify the surface properties of three-dimensional scaffolds and thus promote cell adhesion and proliferation for tissue engineering.

Biomimetic materials for tissue engineering

“…Our group recently developed a few techniques to effectively modify the internal pore surfaces of 3D porous polymer scaffolds. For example, a pre-fabricated 3D PLLA scaffold was immersed in a gelatin solution in a solvent mixture (e.g., dioxane and water) [121]. Then the scaffold was moved to a non-solvent of the scaffold material (water in this case).…”

“…This is a facile and permanent surface modification technique for complex 3D porous scaffolds. The entrapped gelatin (or other molecules if desired) can not be washed off in water or in an aqueous tissue culture medium [121].…”

Magnesium-Containing Nanostructured Hybrid Scaffolds for Enhanced Dentin Regeneration

“…Ideally, a scaffold should be biodegradable, biocompatible, promote cellular interactions and tissue development, and possess proper mechanical properties. [10][11][12][13][14] In an attempt to regenerate dentin and pulp, several types of scaffolds, including collagen, poly(lactideco-glycolide), synthetic peptides, and porous ceramic, have been tested with dental pulp stem cells (DPSCs) both in vitro and in vivo. 7,[15][16][17][18] However, all of those studies regenerated only limited dental tissues randomly distributed inside the scaffolding constructs, indicating that singlecomponent scaffolding materials cannot provide the proper microenvironment for DPSC adhesion, proliferation, and differentiation.…”

A novel model of optimum nanofibre distribution in nanofibre scaffold structure by genetic algorithm method

“…The maximum number of fibres in each angle can be 10 , 15 , 20 , 25 , 30 and 35 . As the maximum number of fibres in each angle is 10, a chromosome can be [7,8,6,2,5,1,3,2,8,6,10,7,8,1,3,6,8,9]; it means that there are seven fibres in À90 , eight fibres in À80 and so until 80 where there are nine fibres. Note that the total fibres in this individual is 100, too.…”

“…The uniform distribution leads to improvement in filtering ability, mean strength, uniform transmission of flowed, heat and vapour [3][4][5]. The optimum distribution model of nanofibre formation in tissues can be introduced based on the angle of fibre direction and the number of fibres in every direction.…”