Fabrication And Properties Of Poly(Lactic Acid) (PLA) And PLA/Hydroxyapatite With Porous Scaffolds

Highly porous biodegradable polymer scaffolds have been extensively utilized as temporal templates for regeneration of various new tissues in recent years. A highly open porous structure of scaffold with well interconnected pores is required to achieve cell proliferation and differentiation. Therefore, meeting the structures of organisms is essential to the preparation of scaffolds. Among many fabricated methods, solvent casting/porogen leaching (SC/PL) is one of the most widely preparation of scaffolds because of its low experimental conditions and advantages of controlled porosity and pore size. However, the SC/PL has obvious disadvantages, such as the shrink of scaffold volume during the process of solvent evaporation, which leads to the traditional SC/PL method only suitable for the preparation of thin porous membrane.In this work, we reported a novel approach for facile fabrication of highly porous three-dimensional scaffolds, which was called solvent casting/vacuum volatilization/porogen leaching (SC/VV/PL). Sodium chloride was used as porogen and chloroform was employed as solvent in this method. PLA pure scaffold and PLA/HA composite scaffold were fabricated via SC/VV/PL. The pore structure, porosity, pore size, mechanical property, hydrophilicity and non-cytotoxic of these scaffolds were tested. The results showed that fabricated scaffolds had obtained the good pore-pore connectivity scaffolds when the distribution sodium chloride size was wider. The pore size of scaffolds was well coincided with that of the employed sodium chloride particles. Porosity and compressive modulus can be adjusted by the control of dosage of sodium chloride. The results of MTT assay not only confirmed the non-cytotoxicity of the PLA scaffolds but also verified the complete removal of solvent and salt in the scaffolds using the proposed SC/VV/PL method. The compressive modulus and hydrophilicity of PLA scaffold can be improved by adding HA particles from the results of compressive modulus, contact angle and water sorption, The conclusions above confirmed that the SC/VV/PL method can fabricate three-dimensional scaffolds that its structures were controllable and properties were adjustable. This approach overcame its limitation that the tradition porogen leaching method fabricated not more than 2mm thickness porous membranes.