Adhesion and Growth of Vascular Smooth Muscle Cells on Nanostructured and Biofunctionalized Polyethylene

Abstract

Cell colonization of synthetic polymers can be regulated by physical and chemical modifications of the polymer surface. High-density and low-density polyethylene (HDPE and LDPE) were therefore activated with Ar+ plasma and grafted with fibronectin (Fn) or bovine serum albumin (BSA). The water drop contact angle usually decreased on the plasma-treated samples, due to the formation of oxidized groups, and this decrease was inversely related to the plasma exposure time (50–300 s). The presence of nitrogen and sulfur on the polymer surface, revealed by X-ray photoelectron spectroscopy (XPS), and also by immunofluorescence staining, showed that Fn and BSA were bound to this surface, particularly to HDPE. Plasma modification and grafting with Fn and BSA increased the nanoscale surface roughness of the polymer. This was mainly manifested on HDPE. Plasma treatment and grafting with Fn or BSA improved the adhesion and growth of vascular smooth muscle cells in a serum-supplemented medium. The final cell population densities on day 6 after seeding were on an average higher on LDPE than on HDPE. In a serum-free medium, BSA grafted to the polymer surface hampered cell adhesion. Thus, the cell behavior on polyethylene can be modulated by its type, intensity of plasma modification, grafting with biomolecules, and composition of the culture medium.

Surface modification of the laser sintering standard powder polyamide 12 by plasma treatments

“…After exposure to atmospheric air plasma (rich in oxygen), the hydrogen bonding with water becomes easier and polar components are increased on the PA12 particles, which facilitate the PA12 powder wettability . However, as seen in Figure c, only a part of the powder was fully dispersed which is possibly because of density heterogeneity, as shown in Table , which summarizes the density and volume changes of PA12 caused by plasma treatments.…”

Epi‐fluorescence Microscopy as a Tool for Relative Quantification of the Anti‐Biofouling Character of Atmospheric Pressure Plasma‐Polymerized Biomaterials

“…Ideal common substrates (silicon or gold) are rejected so as to prevent any fluorescence quenching phenomenon that may interfere with the labeled protein fluorescence . Therefore, pp ‐PEG coatings were synthesized on HDPE (high density polyethylene) substrates, well known to promote protein adsorption . A scratch on the samples allowed removing a part of the pp ‐PEG coating and revealing the HDPE substrate.…”

“…The high sensitivity of fluorescence‐based techniques renders them very suitable for this purpose. For instance, most of the previous studies use Total Internal Reflection Fluorescence Microscopy (TIRFM), TIRFM coupled with photobleaching recovery, confocal or epi‐fluorescence microscopies . However, to our knowledge, despite the fact that epi‐fluorescence microscopy is already used in other plasma‐polymer applications, it is surprisingly under‐used with plasma‐synthesized biomaterials, especially when it comes to quantify protein adsorption.…”

Facile fabrication and mechanistic understanding of a transparent reversible superhydrophobic – superhydrophilic surface

“…Fabrication of superhydrophobic and superhydrophilic surfaces has drawn significant attention in recent times due to innumerable applications of such surfaces in energy, water, health care, fundamental research as well as day-to-day activities 1 . Some of the specific applications of such extreme wetting surfaces include oil – water separation 2,3 , fog harvesting 4 , waste water treatment, lab on a chip device 5 , self – cleaning 6 , blood – plasma separation 7 and cell biology 8–12 . Wetting behaviour of these surfaces is mainly governed by the microstructure (roughness) and chemical composition of the surfaces that requires deep fundamental understanding 13 .…”