Fabrication of porous biodegradable polymer scaffolds using a solvent merging/particulate leaching method

Abstract

This study developed a solvent merging/particulate leaching method for preparing three-dimensional porous scaffolds. Poly(L-lactic-co-glycolic acid) (PLGA) and sodium chloride particles were dry-mixed and cast into a special mold, through which a liquid could pass due to a pressure difference. An organic solvent was then poured into the mold to dissolve and merge the PLGA particles under negative pressure. A nonsolvent was conducted into the PLGA/salt composite to solidify and precipitate the merged PLGA matrix. Finally, a large amount of water was passed through the mold to leach out the salt particles so as to create a porous structure. The results revealed that a highly porous three-dimensional scaffold (>85 vol %) with a well interconnected porous structure could be achieved by this process. Porosity and the pore size of the scaffold were controlled using the ratio and the particle size of the added salt particles. A larger-volume scaffold was produced using a larger mold. This work provides a continuous and simple procedure for fabricating a bulk three-dimensional porous scaffold for tissue engineering.

Fabrication and Characterization of Three-Dimensional Electrospun Scaffolds for Bone Tissue Engineering

“…At each time point (7,14,21, and 28 days), the media was removed, then 300 μl of fresh media and 60 μl of the MTS solution were added to each well and incubated at 37°C with 5 % CO 2 for 3 hours. After incubation, 300 μl of the mixture was transferred to a 48-well plate and diluted with 300 μl of DI water.…”

“…Porosity and pore size depend on the porogen size [19][20][21]. While the use of porogens provides the control of pore size and porosity, interconnectivity of the pores can still be a problem [10,11,[20][21][22][23]. Heat sintering is a technique where the polymer microspheres are heated above glass transition (Tg) of polymer and held for certain period of time and then cooled down to room temperature.…”

Preparation of interconnected poly(ε-caprolactone) porous scaffolds by a combination of polymer and salt particulate leaching

“…In some cases, the resulting scaffolds can have well interconnected macroporous structure with limited core/skin effect [15]. Other techniques include the use of particle aggregation to create macroporous three-dimensional structures with porosity up to 35% [17][18][19] and solid freeform fabrication technique (SFF) such as 3D-printing [20], selective laser sintering [21], 3D-plotting [22], fused deposition modeling [2,23]. These techniques are time consuming and are limited to pore sizes greater than 50 mm and to porosity lower than 70%.…”

Fabrication of poly(lactic acid) scaffolds by a modified solvent casting/porogen leaching method

“…4(d). With reference to the results of [13,14], it is expected that the porosity and pore size can be adjusted by varying the salt-to-polymer ratio and the particle size, respectively.…”

“…In order to resolve the problem, Liao et al [13] reported a method for preparing three dimensional polymeric scaffolds with controlled pore size and porosity. Poly(L-lacticcoglycolic acid) (PLGA) polymer particles were dry-mixed with salt particles and then cast into a Teflon mold.…”