Transmission electron microscopy of lipid vesicles for drug delivery: comparison between positive and negative staining.
Lipid-containing nanostructures, in the form of solid lipid nanoparticles or iron oxide nanoparticles (NPs) coated with a lipid shell, were used as case studies for assessing and optimizing staining for transmission electron microscopy structural and compositional characterization. These systems are of paramount importance as drug delivery systems or as bio-compatible contrast agents. In particular, we have treated the systems with a negative (phospshotungstic acid) or with a positive (osmium tetroxide) staining agent. For iron-oxide NPs coated with the lipid shell, negative staining was more efficient with respect to the positive one. Nevertheless, in particular cases the combination of the two staining procedures provided more complete morphological and compositional characterization of the particles.
Bello
Valentina
V
Department of Physics, University of Padova, via Marzolo 8, I-35131 Padova, Italy. bello@padova.infm.it
Mattei
Giovanni
G
Mazzoldi
Paolo
P
Vivenza
Nicoletta
N
Gasco
Paolo
P
Idee
Jean Marc
JM
Robic
Caroline
C
Borsella
Elisabetta
E
D016503:Drug Delivery Systems; D008055:Lipids; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D053758:Nanoparticles; D013194:Staining and Labeling / Q000379:methods*
D008055:Lipids