PLLA powders (Purity: tionigand inherent viscosity: 1.46 dl/g) were provided from Shenzhen Polymtek Biomaterial Co., Ltd. (Shenzhen, China). GO powders (purity > 98%) were obtained from Chengdu Organic Chemicals Co., Ltd. (Chengdu, China). The composition of phosphate-buffered solution (PBS) was NaCl, KCl, Na2HPO2H2O, and KH2PO4, which was provided from Sigma-Aldrich (Beijing, China). SBF was purchased from Qingdao Jieshang Biological Technology Co., Ltd. (Qingdao, China). Human osteoblast-like MG-63 cells were supplied from the American Type Culture Collection (ATCC, Rockville, MD).
Three-dimensional porous PLLA and PLLA/GO scaffolds with 0.3%, 0.6%, 0.9%, and 1.2% GO were prepared by SLS. The powders were evenly laid on the sintering platform and selectively sintered according to the pre-planned scaffold models, and the sintering platform would be lowered to a corresponding height when a layer of powders was sintered and then a layer of powders was applied again, sintering layer by layer, and finally obtaining the required scaffolds. The processing parameters were applied as follows: Spot size of 1.2 mm, laser power of 2.2 W, and laser scanning speed of 100 mm/min.
Three-dimensional porous PLLA and PLLA/GO scaffolds with 0.3%, 0.6%, 0.9%, and 1.2% GO were prepared by SLS. The powders were evenly laid on the sintering platform and selectively sintered according to the pre-planned scaffold models, and the sintering platform would be lowered to a corresponding height when a layer of powders was sintered and then a layer of powders was applied again, sintering layer by layer, and finally obtaining the required scaffolds. The processing parameters were applied as follows: Spot size of 1.2 mm, laser power of 2.2 W, and laser scanning speed of 100 mm/min.