Uc7 ultra thin slicer

RAW264.7 cells infected with Salmonella for 10 h were analyzed by electron microscopy. The cells were collected and centrifuged after being treated with an electron microscope-fixing solution. Then, 1% agarose solution was added for pre-embedding. The samples were fixed with 1% osmium tetroxide at room temperature for 2 h and washed twice with PBS. After dehydration with ethanol and acetone, the samples were embedded, permeated, and dried overnight at 37 °C, and polymerized for 48 h at 60 °C. Thin slices were obtained using a Leica UC7 ultra-thin slicer, and then stained and placed on a 150-mesh copper grid. The copper grid was placed in a copper grid box and air-dried overnight in a dark room. Images were obtained using an HT7800/HT7700 (Hitachi) transmission electron microscope.

At the end of the soil drought treatment, square leaf samples (0.5 cm × 0.5 cm) were cut near the central vein of the second leaf of the oat plants, and this process was repeated three times. The leaf samples were rapidly fixed in 2.5% (v/v) glutaraldehyde for 4 h, rinsed in 0.1 M phosphoric acid buffer (PBS, pH 7.4), fixed in 1% osmotic acid buffer for 2 h and then washed three times in PBS. Then, gradient dehydration was performed on the leaves with ethanol solutions at different concentrations. After 8 h of immersion in Spurr resin at 70 °C, the sections were sliced with a Leica UC7 ultrathin slicer. Then, the cells were double-stained with uranium acetate and lead citrate, and the ultrastructure was observed by a Tecnai G2 20. For SEM analysis, the samples were fixed with 3% (w/v) glutaraldehyde for 3 h and rinsed in 0.1 M phosphoric acid buffer (PBS, pH 7.4). Then, gradient dehydration was performed on the leaves with ethanol solutions at different concentrations, after which the plants were allowed to dry naturally. The dried samples were observed by a Hitachi-SU8100 instrument after being sprayed with gold–palladium [48 (link)].