Supra 35

Scanning electron microscopy (SEM) with a Zeiss SUPRA 35 (Zeiss, Oberkochen, Germany) and an OLYMPUS IX 51 (Olympus, Tokyo, Japan) inverted fluorescence microscope was used for qualitative evaluation to confirm the presence of C. albicans on the surfaces and inside the specimens (the potential penetration was evaluated on fractured surfaces—interior of specimens). During the SEM investigations, we randomly chose five halves of the fractured specimens after the tensile strength and flexural strength tests were investigated (a total of 10 halves of the specimens for each exposition condition). Observations were performed at accelerating voltages of 15 kV, and all samples were gold sputtered [7 (link)]. The samples (five for each condition) for fluorescence microscopy were carefully rinsed in PBS, then 1–2 drops of Calcofluor White Stain (Sigma-Aldrich, St. Louis, MO, USA) were placed on the microscopic glass, the investigated surface was placed in it, and after 1–2 min of incubation, it was observed at room temperature under UV light using an inverted fluorescence microscope. Fungal organisms appear fluorescent bright green to blue because the Calcofluor White Stain is a non-specific fluorochrome that binds with the cellulose and chitin contained in the cell walls of fungi and other organisms.

Morphology and size of the microcapsule powder were evaluated by scanning electron microscopy (SEM). The Zeiss Supra 35 (Berlin, Germany) electron microscope was equipped with an electron gun with field emission, a GEMINI electron optical column, and an oil‐free vacuum system. A layer of gold coating (2 nm) was applied to each of the mounted samples prior to analysis. Observations were made at magnifications in the range of 5 000–25 000.

Morphological investigation of bare and functionalized Ag NPs was performed with transmission electron microscopy (TEM) using a Tecnai microscope (120 kV) and 4k × 4k Eagle camera (Thermofisher, USA). A Zeiss Supra 35 scanning electron microscope (SEM) with field-emission gun (FEG) equipped with scanning transmission electron microscopy (STEM) detector was employed to characterize the distribution of nanoparticles dispersed on copper grid with holely carbon film. The same samples were observed again in Jeol 2100plus transmission electron microscope (TEM) operated at 200 kV to observe the details of individual nanoparticle using double-tilt sample holder and Gatan Rio16 camera with 4k × 4k resolution. The extinction spectra of Ag colloidal solutions were recorded by UV-vis spectroscopy (Shimadzu 2700 UV-vis spectrometer). The hydrodynamic size were measured by dynamic light scattering (DLS) (CORDOUAN Visco Kin). The surface tension and viscosity of the SERS inks were studied by AquaPi portable tensiometer and viscometer DV-II (BROOKFIELD), respectively. The Raman spectra and images were obtained using a Horiba XploRA PLUS Raman microscope equipped with a 638 nm laser.

Fillers were added to 99.8% ethanol, ultrasonically homogenized, and dropped on carbon tape. Polymerized samples for composite morphology observations measured 10 × 2 × 2 mm. Two types of specimens were used. The first type was subjected to the standard procedure which involved wet-grinding and polishing using diamond pastes. The other type was immersed in liquid nitrogen and broken. Composite samples after polishing were also etched with orthophosphoric acid. All samples were sputtered with gold. Observations were performed using a Zeiss SUPRA 35 scanning electron microscope (Zeiss, Oberkochen, Germany) at accelerating voltages from 3 kV to 20 kV.

Samples for composite morphologies observations measured 40 mm × 10 mm × 6 mm and were crosslinked in a stainless steel mold, individually immersed in liquid nitrogen, broken, and sputtered with gold.
After tensile bond strength tests observations of failures, and cross-sections showing bonding zone between poly(methyl methacrylate) (PMMA) resin and silicone composites were carried out. Cross-sections were obtained by breaking samples in liquid nitrogen. All samples were sputtered with gold.
Investigations were realized using a Zeiss SUPRA 35 scanning electron microscope (Zeiss, Oberkochen, Germany) at accelerating voltages from 1 kV to 10 kV.