Preparation And Characterization Of Poly (Lactic Acid) Scaffold For Tissue Engineering

The core of tissue engineering is to build a complex three-dimensional space ofcells and porous materials, which is to promote the implantation of cell’s adhesion,proliferation, differentiation and metabolism. Therefore, how to effectively prepared tomeet the needs of the porous scaffold is of concern. Among many fabricated methods,solvent casting/porogen leaching (SC/PL) is one of the most widely preparation ofscaffolds because of its low experimental conditions, simple experimental operationand advantage of controlled porosity and pore size. However traditional SC/PL methodcan only prepare thin porous membrane, such as two or three millimetre. In this work,our group use independent invention method, which was called solvent casting/vacuumvolatilization/particulate leaching (SC/VV/PL) to fabricate the PLA porous scaffolds,including the following aspects.1. Using SC/VV/PL method to prepare the three dimensional porous scaffolds, thescaffold’s holes uniformLy distributed, between the hole and hole there are some smallholes, which is description of the scaffold has a good hole connectivity, the scaffold’spore size is the same as the particle of porogen. Porosity test result is that all scaffold’sporosity are more than89%. The scaffold compression modulus is1.95±0.2MPa,compressive modulus decreased with the increase of porosity. L929cell toxicity testresults confirmed that scaffold does not exist cytotoxic. Moreover, using differentdiameter tubular glass mould, this method can also be prepared various tubular porousscaffolds.2. Using SC/VV/PL method to prepare the gradient porous scaffold, its pore sizevaries along the axial. The scaffold’s porosity varies from87.34±0.3%to91.24±0.3%. Pore size from166±41μm to453±18μm. The compression modulus from thefirst layer’s2.12±0.08MPa to the thirteenth layer’s2.56±0.18MPa showed anincreasing trend. Priority in the use of ink penetration characterization of the scaffoldshole an hole connectivity, the result showed that the graded macroporous PLA scaffoldwas well interconnected in each layer and their boundaries.3. Using SC/VV/PL method prepared pore size radial gradient porous scaffolds.The average pore diameter of the gradient porous scaffold layers is between175±30μm and341±23μm, the porosity are greater than87.9±1.2%. The different layers ofporous scaffolds stress-strain curves show that, under small stress, the materials showsliner elastic, when the strain continues to increase from30%to40%, the stress evenlyto increase, when the strain is more than40%, the stress rapidly increase. TGA testresults confirmed that the scaffold does not exist porogen and solvent residue.In summary, our group using independent invention method which was calledSC/VV/PL prepare PLA porous scaffold, this method inherits all the advantages of the traditional SC/PL method, and overcome the SC/PL method can only suitable for thepreparation of the two or three thin porous membrane. In addition, there are someadvantages of SC/VV/PL method, such as, under vacuum solvent evaporation fasterand more thorough, and suitable for preparation of a variety of types of scaffolds.