Effects of Varying Heptylamine and Propionaldehyde Plasma Polymerization Parameters on Mesenchymal Stem Cell Attachment

This paper investigated the impacts of two deposition times (30 s, 60 s) and discharge powers (20 W, 50 W) on the resultant chemical and physical properties of plasma polymers (pp) formed using heptylamine (HA) or propionaldehyde (PA) monomers. Pinhole-free pp films were formed on all surfaces at deposition rates that varied according to both the time and power employed. XPS and ToF-SIMS analysis showed that power has a more of an effect than time on the chemical properties of the pp, which may be attributed to differences in monomer fragmentation and cross-linking. Mesenchymal stem cell (MSC) adhesion did not vary on the four different HApp surfaces, whereas a negative correlation between cell attachment and increasing plasma energy was observed on PApp surfaces. This suggests that the presence of oxygenated groups, particularly aldehyde and carboxylic groups, may have a dominant impact on MSC adhesion to these functional polymer substrates.