G2 20 twin microscope

Spurr's resin blocks containing the sectioned leaves with preserved polysaccharide antigenicity and fine structure were immunogold labeled for callose. Preloaded nickel grids carrying ultrathin leaf sections or cell wall or PD fractions were incubated with the monoclonal anti-b-(1,3)-glucan antibody (1: 20 dilution, Biosupplies) or the PDLP5 polyclonal antiserum (1: 20 dilution) at room temperature for 1 h and then at 4 C overnight. Goat anti-mouse or anti-rabbit immunoglobulin G antibody conjugated with 10-nm colloidal gold particles (1:50 dilution, Sigma-Aldrich) was used as the secondary antibody. Before TEM (Tecnai G2 20 TWIN microscope equipped with an Eagle 4k CCD at 120 kV, FEI), the sections were stained with 2% (w/v) uranyl acetate. With regard to the immunogold labeling of callose, both branched and simple PDs of mesophyll cells from 4-week-old functional mature leaf tissues were scored. According to the general definition, these leaves were source leaves.

Cationic nioplexes based on a niosome formulation containing the cationic lipid_1, polysorbate-80 (Tween-80) and FITC-ODN (1 M) were characterized by TEM microscopy. Nioplexes (5 L) were deposited onto glow discharged carbon coated grids for 1 min. The sample was stained with uranyl acetate (2%) for 60 s. Cationic nioplexes were observed by using a TECNAI G2 20 TWIN microscope (FEI, Eindhoven, The Netherlands) at an accelerating voltage (200 keV) in a bright-field image mode. Pictures were obtained from an Olympus SIS Morada digital camera.