Several inorganic and organic sorbents are reported in the literature which can selectively extract uranyl
ions by forming complexes with the chelating functional groups present in them.
Another two washes with buffer were performed before uranyl
acetate staining (1 % uranyl
acetate in 10 % ethanol for 8 hours).
Ultrathin sections were taken with LKB ultramicrotome III and stained with uranyl
acetate and lead citrate.
Samples were stained en bloc within a range of 1/5 stock RR solution and 2% uranyl
acetate (22), then dehydrated in a ascending alcohol series and embedded in epon 812.
Reagents and poison: Electron microscopy reagents (EPON EMBed-812 Kit, uranyl
acetate, osmium tetroxide, lead citrate and glutaraldehyde) were purchased from Electron Microscopy Sciences (Hatfield, PA, USA).
Uranium stock solution (1000 ug mL-1) was prepared from analytical grade uranyl
nitrate in deionized water and further dilutions were made when required.
Post-stain procedures for 100-nm sections observed with electron microscopy varied, with the sample being treated either with (1) 2% aqueous uranyl
acetate (15 min) and 0.5% aqueous lead citrate (1 min) with 3 washes of 20 s with DI water in between; (2) only 2% aqueous uranyl
acetate (15 min); or (3) only 0.5% aqueous lead citrate (1 min).
The hydraulic gradient, volumetric flow rate, and uranyl
ions concentration were monitored over time.
(e) Ultrastructural examination shows osmophilic globular hemoglobin casts in tubular lumen (uranyl
acetate and lead citrate fixation, 10,000x).
For visualization using TEM, uranyl
acetate was used as a negative staining reagent for the liposomes .
Poly(vinyl alcohol) (PVA, Mw of 15kDa), uranyl
acetate dehydrate (98%), dimethyl sulfoxide (DMSO, 99.5%), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), N-hydroxysuccinimide (NHS), fluorescein isothiocyanate (FITC), and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoli-um bromide (MTT) were supplied by Sigma-Aldrich (St.
The ultrathin sections were stained with lead citrate and uranyl
acetate and observed under a Philips CM-120 transmission electron microscope (Philips, Amsterdam, Netherlands).