Tecnai g2 tf20

The worn surfaces of the composites were characterized using an optical microscope (U-25ND25, OLYMPUS, T2,Tokyo, Japan). Nanostructures of the tribofilms were imaged with a scanning electron microscope (SEM, 7610F, JEOL, Tokyo, Japan). Additionally, the changes in the chemical states of the tribofilms were analyzed with X-ray photoelectron spectroscopy (XPS, 250Xi, ESCALAB, Waltham, MA, USA). Moreover, slices of the tribofilm were prepared using focused ion beam (FIB) machining (Quanta 3D FEG, FEI, Hillsboro, OR, USA), and the fractured surfaces were then observed via high-resolution transmission electron microscopy (HR-TEM, TecnaiG2 TF20, FEI, Hillsboro, OR, USA).

The morphology of C. albicans ATCC 90028 was analyzed using TEM following the standard protocol [28 (link)]. Mid-log phase cells were harvested, standardized (A600 ≈ 0.1) and exposed to MIC of lead inhibitors 3a and 3b for 1 h. Cells were then washed thrice with phosphate buffer solution to remove the residual medium and fixed overnight in 2.5% glutaraldehyde in phosphate/magnesium buffer (40 mM K₂HPO₄/KH₂PO₄, pH 6.5–0.5 mM MgCl₂). Cells were washed twice for 15 min in 0.1 M sodium phosphate buffer (pH 6.0) and post-fixed for 2 h in 2% osmium tetroxide. Cells were again washed twice for 15 min in distilled water and then en bloc stained with 1% uranyl acetate (aqueous) for 30 min. After two further washes, cells were dehydrated in 95% and 100% ethanol. Cells were then exposed to propylene oxide for 2×10 min and infiltrated for 1 h in 1:1 propylene/epoxy embedding material (Epon) mixture and then overnight in fresh Epon. After polymerization for 48 h at 60°C, ultrathin sections were cut using a microtome (LeicaEM UC6) and transferred to a copper grid. Samples were stained with uranyl acetate (saturated solution of uranyl acetate in 50% alcohol) followed by lead citrate. Samples were washed three times in Milli-Q (MQ) water and dried by touching Whatman filter paper. Sections were examined with a FEI Tecnai G² TF20 transmission electron microscope at 200 KV.

Nanoparticle size and polydispersity was determined using a Malvern ZEN3600 dynamic light scattering (DLS) instrument with a disposable sizing cuvette. Lyophilization of polymer samples was performed using a Labconco Freezone 4.5. TEM image was obtained on a FEI Tecnai G2 TF20 high resolution TEM operated with an accelerating voltage of 200 kV.