To study the effect of the pore size on the morphology of the adhered HAECs, confocal

microscopy and SEM were employed. Figure  2 shows representative AZD1152 purchase images of HAECs growing on nanoporous Si substrate and on flat Si as control, after 48 h of incubation. On porous silicon, cells appeared elongated and spread with protrusions, and the development of the filopodia is visible at the cell borders (Figure  2b,c), which is because the nanopores may not anchor firmly to the surface. The same shape is observed on flat silicon (Figure  2a). Figures  3 and 4 illustrate the results obtained on macroporous silicon substrates. These indicate the effect of the surface in the cell adhesion and spreading, Selleck CHIR98014 compared to the flat Si. The cell migration after 48-h

incubation on pSi 1 to 1.5 μm results in 2-D and 3-D shape of the HAEC, while the cells on nano and flat silicon show only 2-D migration movements. In the macroporous substrate, the cell appears with a well-spread cytoskeleton with formation of protrusions out of the cell AZD2281 chemical structure membrane and is visible how part of it penetrates inside the macropore (Figure  4b,d). Filopodia is not present in this type of substrate. Figure  5 shows confocal imaging for HAEC culture on flat, macro-, and nanoporous silicon modified with APTES. The samples were washed after 48 h of incubation, and then, the remaining cells were fixed and labeled with

actin phalloidin and NucGreen. Figure 1 Morphological characterization of porous silicon substrates. Top view ESEM images of (a) macroporous silicon substrate with a pore diameter of 1 to 1.5 μm and (b) nanoporous silicon with pore sizes less than 50 nm. Figure 2 SEM characterization of endothelial cells on nanoporous silicon. SEM images of HAEC culture after 48-h incubation on modified silicon substrates: (a) flat silicon and (b, c) nanoporous silicon. Figure 3 SEM characterization Rucaparib purchase of HAECs on macroporous silicon. SEM images of HAEC culture after 48-h incubation on modified silicon substrates: (a) flat silicon and (b, c, d) macroporous silicon substrates. Figure 4 Images of HAECs growing on macroporous silicon substrates. (a, b, c, d) SEM images of HAEC culture after 48-h incubation on modified macroporous silicon at different magnification. Figure 5 Fluorescence confocal microscopy. Confocal imaging for HAECs cultured on three different substrates at 37°C for 48-h incubation. The actin filaments were stained with actin-stain 670 phalloidin for 30 min (red), and the nucleus was stained with NucGreen Dead 488 for 10 min (green). From fluorescence microscopy, we notice that the fluorescence images provided limited information on cell morphology to qualify the cell development on these three types of silicon substrates. On flat silicon, the cell looks more spread over the substrate (flat shape).