Esem xl 30 feg

HMEECs were cultured on glass cover slips and were infected with bacteria for varying time periods. After incubation, the cells were washed 5 times with warm phosphate buffered saline (PBS, pH 7.4, Cellgro, Manassas, VA)) buffer to remove unbound bacteria and were then processed for SEM. Samples were fixed in 2% glutaraldehyde (Electron Microscopy Sciences, Hatfield, PA) in PBS buffer followed by three changes of PBS buffer for 10 min each. The samples were then post–fixed in 1% osmium tetroxide (Electron Microscopy Sciences, Hatfield, PA) in PBS buffer for 45 min and rinsed in three changes of PBS buffer for 10 min each. The samples were dehydrated in a graded series of ethanol, dried in hexamethyldisilazane (HMDS) (Electron Microscopy Sciences, Hatfield, PA) and mounted on carbon adhesive tabs fixed to metal stubs. The samples were coated with palladium in a plasma sputter coater and viewed in a scanning electron microscope (FEI, ESEM-FEG XL-30).

Cancer cell samples with the nano-clays were imaged in SEM mode in an FEI ESEM-FEG XL-30 at the Miller School of Medicine, University of Miami, Florida. Before SEM imaging, samples were preserved in 2% glutaraldehyde fixative in PBS buffer and stored in the refrigerator for at least 2–3 h. Samples were washed in three changes of PBS buffer for 10 min each and were then post-fixed in 1% osmium tetroxide in PBS buffer for 45 min and then rinsed in three changes of PBS buffer for 10 min each. The cells were then dehydrated in a graded series of ethanol (20, 50, 70, 95, and 100%). After dehydration, samples were dried in three changes of HMDS and left to outgas overnight. Cells on coverslips were then placed on aluminum stubs covered with carbon adhesive tabs. Pelleted cells were placed directly on the carbon adhesive tabs on the stubs.

A qualitative analysis of the effects of usage on tip shape and surface topography was performed by using scanning electron microscopy (FEG ESEM XL 30; FEI, Hillsboro, OR, USA). The entire sample was divided into four groups (3 groups of 11 teeth and 1 group of 10 teeth): images of the ultrasonic tip used in each group were captured at 35×, 100× and 200× magnification and compared by 2 different investigators (F.B. and A.R.) with the images of a brand-new tip.

The length and diameter of BFs with different opening times were measured using a stereoscopic microscope (Camera Model-Li165; Lumenera, Ottawa, ON, Canada), and thirty random samples from each category were selected. The microstructure of the samples was observed using an environmental scanning electron microscope (FEG-ESEM-XL30; FEI Company, Hillsboro, OR, USA).

After incubation for 7 days, we assessed cell morphologies on BCP granules under the four applied treatments. For this evaluation, cells were seeded at an initial density of 2 × 10⁴ cells/well. Cell morphology was investigated through cytoskeleton staining and scanning electron microscopy (SEM, ESEM XL 30 FEG, FEI, Eindhoven, Netherlands). With regards to cytoskeleton staining, OB cells were subjected to co-staining with Rhodamine Phalloidin (ThermoFisher, Grand Island, NY, United States) and DAPI, which aid in visualizing F-actin and cell nuclei. Briefly, cells were rinsed with DPBS, fixed in 4% paraformaldehyde, followed by permeabilizing with 0.1% Triton X-100 and blocking with 1% BSA solution. After that, cells were co-stained with the indicated fluorescent regents and visualized via a CLSM under Ex/Em (540/565 nm) wavelength. For SEM observation, OB cells in various treatment groups were treated with an SEM fixation solution without light and dehydrated through varying gradient ethanol. Lastly, the morphologies of OB cells were detected via SEM after spray-coating with 4 nm thick gold.

For the graphene-reinforced batches, in addition to the as-supplied raw materials, the 1–3 mm tabular alumina fraction was coated by graphene oxide (GO). The grains were coated with a highly viscous dispersion of GO in water (see above) using a simple dip-coating device developed in-house. Coated particles were then dried in air atmosphere at 60 °C for 48 h. From weights (before and after the coating), it was determined that the sample of coated coarse grain alumina contained approximately 0.4 wt% of GO, which was a reasonable amount for our further experiments.
As the actual thickness of the coating consisted of a few atomic layers, no additional particle size distribution and true density analyses were performed for the coated aggregates. Instead, these were taken as direct replacement of the uncoated particle fraction in the reference batch. Nevertheless, the effectiveness of the coating procedure was investigated by scanning electron microscopy (SEM) (ESEM XL30FEG, FEI Company, Hillsboro, OR, USA).