Formvar carbon coated 200 mesh grids

The morphology and core-shell structure of NanoC were determined using transmission electron microscopy (TEM, Philips CM10, Philips Electron Optics, Eindhoven, The Netherlands) at an acceleration voltage of 80 kV and ranging from 92,000 to 130,000. The TEM sample stage was prepared using a copper grid. For detailed morphological analysis, specimens were processed for transmission electron microscopy observation using the conventional negative staining procedure. Eighty microliters of nanohydrogel were adsorbed onto formvar carbon-coated 200 mesh grids (Agar Scientific Ltd., Stansted, UK) for 10 min. Subsequently the grids were incubated with 2% w/v sodium phosphotungstate for 1 min and the excess liquid of the sample was removed by filter paper and the sample dried at room temperature.

The morphology based physical characterization of EV was evaluated using TEM. In brief, 20 µL droplets of purified UF-EV from each pooled group was placed on formvar/carbon-coated 200 mesh grids (Agar Scientific, Stansted, UK). The droplets were allowed to adsorb on the grid for 20 min. Then, the same grids were incubated with 2% uranyl acetate (Polysciences, Warrington, PA, USA) for 5 min and air-dried for obtaining contrasted images of EV. UF-EV were visualized using JEM 1400 TEM (JEOL Ltd. Tokyo, Japan, with Morada TEM CCD camera, Olympus, Hamburg, Germany) at 80 kV. The digital images of EV were captured using a numeric camera (Morada TEM CCD camera, Olympus, Hamburg, Germany).

EVs isolated from serum and urinary supernatant were adsorbed to formvar carbon-coated 200 mesh grids (Agar Scientific Ltd., Stansted, UK) for 20 min. After the grids were dried, they were incubated with 2% (w/v) sodium phosphotungstate for 1 min and the liquid excess was removed with filter paper. After negative staining, specimens were observed by means of a Philips CM10 transmission electron microscope at 80 kV [16 (link)].