Table 2: Surface free energy (SFE, in mJ·m−2) of pristine LDPE, plasma-treated LDPE (plasma), LDPE treated with plasma and then grafted with glycine (Gly), polyethylene glycol (PEG), bovine serum albumin (BSA), colloidal carbon particles (C), or with a combination of BSA and C (BSA+C). is the total SFE of the polymer and consists of nonpolar ( ) and polar components ( ).


Pristine24.5423.161.37
Plasma28.5625.013.55
Gly36.2031.894.31
PEG34.915.0129.90
BSA26.5620.286.28
C26.5919.227.37
BSA+C25.5812.8612.72

The values are the mean of 10 to 15 measurements for each experimental group and were calculated automatically by the Surface Energy Evaluating System (SEE System, Masaryk University, Brno, Czech Rep.).