Fig. 3.

Surface characterization of different scaffolds. (a) The concentration of elements is based on XPS analysis. (b) XPS survey spectra for detection of C, N, and O elements. (c–d) The high-resolution spectrum of C1s/N1s for HDPE, pDA, pDA-E, pDA-EF, and pDA-EFE scaffolds. (e) Transformation of zeta potential of HDPE functionalized with pDA, FIB, and EPL through an LBL fabrication method. (f) Water contact angle measurement. Mechanical tests show no significant difference in the scaffolds' compressive stress (g) and Young's modulus (h). (P ​< ​0.05, n ​= ​3).