Synergetic effect of electrospun PCL fiber size, orientation and plasma-modified surface chemistry on stem cell behavior

Influence of Hydroxyapatite Nanoparticles and Surface Plasma Treatment on Bioactivity of Polycaprolactone Nanofibers

“…A similar type of argon plasma treatment mediated by dielectric barrier discharge in [ 30 ] was not able to render the PCL surface completely wettable. In [ 30 ], the contact angle was reduced from the initial 75° to 52°, at an energy density of 2.5 J/cm 2 . The reason is twofold.…”

“…First, in our case, PCL samples were treated at a substantially higher power density of approximately 17 J/cm 2 . Second, the treatment in [ 30 ] (and similarly in [ 31 ]) was done at low pressure of 5 kPa, and special attention had been paid to samples degasifying from ambient gas residuals. In our case, the intended introduction of polar functional groups to the PCL surface relied on the dissociative interactions of excited argon species with adsorbed water and other oxygen-containing molecules.…”

“…The difference in achieved surface modification is also apparent from the mutual pair comparison of XPS spectra. In [ 30 ] and [ 31 ], the formation of a new carbonyl C=O bond was clearly noticeable. In our case, the amount of already present surface carbonyl was reduced.…”

“…This is important especially for materials with microfibrous topology, where incomplete wetting of such a heterogeneous surface may result in the well-known lotus effect [ 29 ]. The main functional principle behind the plasma activation is the formation of polar functional groups (typically –COOH or –C=O), which are strongly interacting with dipoles of surrounding water molecules [ 30 , 31 , 32 ]. Formation of these groups is observed not only in oxygen-containing but also in inert gas plasmas (i.e., Ar, He, N 2 ).…”

Surface Engineering of Cardiovascular Devices for Improved Hemocompatibility and Rapid Endothelialization

“…Diameter PCL Improved hemocompatibility with large fiber diameter [ 87,101] PCL, PLGA Enhanced EC adhesion and proliferation with small fiber diameter [ 102,103] PLLA Promoted cell migration with large fiber diameter [ 104] PCL Enhanced chondrogenic differentiation of MSC with large fiber diameter [105][106][107] Stiffness PA Inhibited platelet adhesion, spreading and activation on soft substrate [ 108,109] PLL/HA Enhanced EC adhesion, migration, and proliferation on stiff substrate [ 110,111] PLCL/PLLA Inhibited SMC adhesion, induce abnormal phenotype on stiff substrate [ 112,113] PAA Favored cell migration towards soft matrices [ 114,115] PEG Enhanced MSC spreading, favored osteogenesis differentiation on stiff matrices [ 110] Roughness PLGA Inhibited thrombin formation and platelets adhesion on smooth surface [116][117][118] PHMMA Enhanced EC adhesion on rough surface with lotus leaf topography [119,120] PCL Enhanced MSC osteogenic differentiation on specific surface-rough surface [ 121] Alignment PCL, PLCL Enhanced EC oriented migration on aligned fibrous substrate [ 122,123] PLLA Promoted cell infiltration into aligned fibers [ 124] PCL, PLLA Enhanced MSC orientation and osteogenesis differentiation on aligned fibrous substrate [ 125,126] microfiber scaffold (fiber diameter ≈ 6 µm), nanofiber scaffold (fiber diameter <1 µm), outer microfiber bilayer scaffold, and inner microfiber bilayer scaffold, the microfiber scaffold group showed the thickest neotissue regeneration, a SMC layer, and best vascularization in vivo. [89] These results indicated that the surrounding tissue contributes more significantly than the circulating blood in neotissue formation, SMCs' regeneration, and vascularization in the graft wall.…”