Figure 3(b) shows the XRD patterns of nLAP and cnLAP and PBSu, nLBC, and cnLBC scaffolds.
The OD values of the cells cultured on both nLBC and cnLBC were significantly higher than PBSu scaffolds at 1, 3, and 5 days, indicating that coatings of nLAP and cnLAP on PBSu improved the cell proliferation.
The concentrations of Mg, Si, and Li ions in the cell culture medium for both nLBC and cnLBC scaffolds gradually increased with time because these ions were gradually released from the two scaffolds into the medium (dissolution of cnLAP and nLAP).
In in vitro cell experiments, the results showed that only a few cells attached on PBSu scaffolds while a great number of cells attached on both nLBC and cnLBC scaffolds, indicating that the coatings of nLAP and cnLAP on PBSu scaffolds significantly promoted the cell adhesion on the scaffolds.
Previous studies have shown that nLAP could promote cell proliferation and differentiation [8,10].
In this study, the results showed that the Mg, Si, and Li ions were gradually released from both nLBC and cnLBC scaffolds into the cell culture medium with time due to the gradual dissolution of both cnLAP and nLAP on the PBSu scaffolds into the medium.
Furthermore, the results demonstrated that incorporation of Cu into nLAP had no negative effects on cells' responses to cnLAP-coated PBSu scaffolds, indicating good cytocompatibility.
Caption: Figure 1: Transmission electron microscopy (TEM) micrographs of morphology of nano laponite (nLAP, a) and Cu-exchanged nLAP (cnLAP, b), specific surface area (c), and dynamic light scattering (DLS) analysis (d, e) of nLAP and cnLAP.