Fig. 4

Functional analysis of the protein adsorption spectra and adsorption behavior evaluation of the representative adsorbed protein fibronectin (FN). A Number of upregulated proteins on each surface in comparison to the other surfaces. ppAA_ppAC_UP referred to the upregulated proteins in ppAA group compared with those in ppAC group, and the rest acronyms may be deduced by analogy; B GO enrichment analysis of the 34 upregulated proteins on the ppAA surface in comparison to all other surfaces on the biological process (BP), cellular process (CC) and molecular function (MF) level; C) Cluster heatmap of adhesion related adsorbed proteins on four surfaces; protein–protein interaction (PPI) analysis of cell adhesion related adsorbed proteins (D) and adsorbed proteins on ppAA surface (E); F ELISA of adsorbed FN on four surfaces. G Immunofluorescence of RGD sequence of FN exposure on four surfaces; H Molecular dynamics simulation showed stable conformation of adsorbed FN on different chemical surfaces at 60 ns, RGD (red) and PHSRN (purple); I Distance between the RGD and PHSRN in the stable conformation of FN on different chemical surfaces. Significant differences between two groups with a p < 0.05 are presented as follows: a) versus ppAA group, b) versus ppAC group, c) versus ppME group, and d) versus control group