Effects of nanopillars and surface coating on dynamic traction force

The extracellular matrix serves as structural support for cells and provides biophysical and biochemical cues for cell migration. Topography, material, and surface energy can regulate cell migration behaviors. Here, the responses of MC3T3-E1 cells, including migration speed, morphology, and spreading on various platform surfaces, were investigated. Polydimethylsiloxane (PDMS) micropost sensing platforms with nanopillars, silicon oxide, and titanium oxide on top of the microposts were fabricated, and the dynamic cell traction force during migration was monitored. The relationships between various platform surfaces, migration behaviors, and cell traction forces were studied. Compared with the flat PDMS surface, cells on silicon oxide and titanium oxide surfaces showed reduced mobility and less elongation. On the other hand, cells on the nanopillar surface showed more elongation and a higher migration speed than cells on silicon oxide and titanium oxide surfaces. MC3T3-E1 cells on microposts with nanopillars exerted a larger traction force than those on flat PDMS microposts and had more filopodia and long protrusions. Understanding the relationships between platform surface condition, migration behavior, and cell traction force can potentially lead to better control of cell migration in biomaterials capable of promoting tissue repair and regeneration.

Low-Temperature Atmospheric Pressure Plasma Processes for the Deposition of Nanocomposite Coatings

Low-temperature atmospheric pressure (AP) plasma technologies have recently proven to offer a range of interesting opportunities for the preparation of a variety of nanocomposite (NC) coatings with different chemical compositions, structures, and morphologies. Since the late 2000s, numerous strategies have been implemented for the deposition of this intriguing class of coatings by using both direct and remote AP plasma sources. Interestingly, considerable progress has been made in the development of aerosol-assisted deposition processes in which the use of either precursor solutions or nanoparticle dispersions in aerosol form allows greatly widening the range of constituents that can be combined in the plasma-deposited NC films. This review summarizes the research published on this topic so far and, specifically, aims to present a concise survey of the developed plasma processes, with particular focus on their optimization as well as on the structural and functional properties of the NC coatings to which they provide access. Current challenges and opportunities are also briefly discussed to give an outlook on possible future research directions.