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Cryo-TEM

Zheng Y, Lin Z, Zakin JL, Talmon Y, Davis HT, Scriven LE (2000) Cryo-TEM imaging the flow induced transition from vesicles to threadlike micelles. J Phys Chem B 104(22) 5263-5271... [Pg.98]

Pochan D.J., Pakstis L., Ozbas B., Nowak A.P., and Deming T.J. SANS and cryo-TEM study of self-assembled diblock copolypeptide hydrogels with rich nano through microscale morphology. Macromolecules, 35, 5358, 2002. [Pg.158]

Fig. 2 PICsomes formed from oppositely charged building blocks, (a) Chemical structures of the hybrid polypeptides for PICsomes and scheme of the PICsome preparation, (b) Cryo-TEM image of 100-nm-sized PICsomes (scale bar 50 run). Arrows indicate vesicle walls. Adapted from [70] with permission. Copyright 2010 American Chemical Society... Fig. 2 PICsomes formed from oppositely charged building blocks, (a) Chemical structures of the hybrid polypeptides for PICsomes and scheme of the PICsome preparation, (b) Cryo-TEM image of 100-nm-sized PICsomes (scale bar 50 run). Arrows indicate vesicle walls. Adapted from [70] with permission. Copyright 2010 American Chemical Society...
Mortensen, K Tahnon, Y, Cryo-TEM and Sans Microstructural Smdy of Pluronic Polymer Solutions, Macromolecules 28, 8829, 1995. [Pg.616]

Figure 6.3 Cryo-TEM image of the nanoemulsions of the water/polyoxyethylene 4 sorbitan monolaurate/[10% EClOin ethyl acetate] system with an O/S ratio of70 30and a water content of 90 wt%. Figure 6.3 Cryo-TEM image of the nanoemulsions of the water/polyoxyethylene 4 sorbitan monolaurate/[10% EClOin ethyl acetate] system with an O/S ratio of70 30and a water content of 90 wt%.
Regev, D., Backov, R. and Faure, C. (2004) Gold nanopartides spontaneously generated in onion-type multilamellar vesides bilayers. Particle coupling imaged by cryo-TEM. Chemistry of Materials, 16, 5280-5285. [Pg.190]

Fig. 8.6 TEM images of (A) exfoliated sheets of AMP in water (scale bar = 200 nm), and (B) cryo-TEM image of exfoliated AMP organoclay sheets viewed edge-on (scale bar = 50nm). Fig. 8.6 TEM images of (A) exfoliated sheets of AMP in water (scale bar = 200 nm), and (B) cryo-TEM image of exfoliated AMP organoclay sheets viewed edge-on (scale bar = 50nm).
Fig. 10 (a) Chemical structure of PEG-6-PCL copolymer, (b) CLSM image of PEG-6-PCL polymersomes containing membrane-encapsulated Nile Red (2 mol%) and aqueous entrapped Calcein dyes. Scale bar 5 pm. (c) Cryo-TEM image of PEG-6-PCL polymersomes. Scale bar 100 nm. Reprinted from [228] with permission... [Pg.86]

Figure 5.9 Transmission electron microscopy (TEM) photographs of 3 wt % fluorinated glu-cophospholipid (13) dispersion at room temperature (a) cryo TEM (b) freeze-fracture TEM. Reprinted from Ref. 50 with permission of Academic Press. Figure 5.9 Transmission electron microscopy (TEM) photographs of 3 wt % fluorinated glu-cophospholipid (13) dispersion at room temperature (a) cryo TEM (b) freeze-fracture TEM. Reprinted from Ref. 50 with permission of Academic Press.
The more recently developed cryo-TEM technique has started to be used with increasing frequency for block copolymer micelle characterization in aqueous solution, as illustrated by the reports of Esselink and coworkers [49], Lam et al. [50], and Talmon et al. [51]. It has the advantage that it allows for direct observation of micelles in a glassy water phase and accordingly determines the characteristic dimensions of both the core and swollen corona provided that a sufficient electronic contrast is observed between these two domains. Very recent studies on core-shell structure in block copolymer micelles as visualized by the cryo-TEM technique have been reported by Talmon et al. [52] and Forster and coworkers [53]. In a very recent investigation, cryo-TEM was used to characterize aqueous micelles from metallosupramolecular copolymers (see Sect. 7.5 for further details) containing PS and PEO blocks. The results were compared to the covalent PS-PEO counterpart [54]. Figure 5 shows a typical cryo-TEM picture of both types of micelles. [Pg.90]

Fig.5 Cryo-TEM pictures of metallosupramolecular PS2o-[Ru]-PEC>7o (a) and covalent PS22-PEO70 (b) aqueous micelles. Arrows in a indicate isolated micelle and cluster of micelles. Reprinted with permission from [54]. Copyright (2004) Springer... [Pg.91]

Fig. 9 Cryo-TEM picture of vesicles formed by the PMAA49-PDMAEMA11 ampholytic copolymer in water at pH = 9. Reprinted with permission from [174], Copyright (2000) American Chemical Society... Fig. 9 Cryo-TEM picture of vesicles formed by the PMAA49-PDMAEMA11 ampholytic copolymer in water at pH = 9. Reprinted with permission from [174], Copyright (2000) American Chemical Society...
Fig. 20 Cryo-TEM image of isolated micelles and segmented rods made from miktoarm ABC block copolymers containing PEO, PB and perfluorinated polyether blocks (scale bar is 50 nm). A schematic representation of the stacking of block copolymer chains in segmented worms is also shown. Reprinted with permission from [284], Copyright (2004) American Association for the Advancement of Science... Fig. 20 Cryo-TEM image of isolated micelles and segmented rods made from miktoarm ABC block copolymers containing PEO, PB and perfluorinated polyether blocks (scale bar is 50 nm). A schematic representation of the stacking of block copolymer chains in segmented worms is also shown. Reprinted with permission from [284], Copyright (2004) American Association for the Advancement of Science...
Figure 11.16 is a cryo-TEM image of G10 PAMAM dendrimers in water. The cryo technique involves flash freezing of the dendrimer solution as a thin film on a grid and is described elsewhere [20]. Individual dendrimers appear to be organized into an array of single dendrimer thickness. While there are complicating factors due to the sample preparation, the picture is consistent with... [Pg.277]

Morphology. Structural details were visualized by cryo-TEM. Figure 1A is a cryo-TEM image of a sample with an entrapped oligonucleotide-to-lipid ratio of 0.13 mg/mg. It confirms the coexistence of unilamellar liposomes with bi- and multilamellar liposomes. The membranes of the latter are in close contact. The inset of Figure 1A is an expanded view of a multilamellar... [Pg.136]

G-50 column and eluted in 2-(N-Morpholino) ethansulfonic acid hydrate (MES)/N-(2-Hydroxyethyl)piperazine-N-(2-ethane-sulfonic acid) (HEPES) buffer pH 7.2 (50 mM MES, 50 mM HEPES, 75mM NaCl) to remove unencapsulated BPs. Several formulations with different sizes were obtained (0.6, 0.4, 0.2, and 0.1 pm). Liposome size and morphology was determined by dynamic light scattering and cryo-TEM microscopy (Fig. 1). [Pg.192]

Figure 1 Cryo-TEM microscopy of DSPC DSPG CHOL liposomes obtained by thin-film hydration method and extruded through 0.2-pm polycarbonate membranes. Abbreviations. DSPC, l,2-distearoyl-s -glycerol-3-phosphocholine DSPG, 2,2-distearoyl-5 -glycerol-3[phosphor-rac-(l-glycerol)] CHOL, cholesterol. Figure 1 Cryo-TEM microscopy of DSPC DSPG CHOL liposomes obtained by thin-film hydration method and extruded through 0.2-pm polycarbonate membranes. Abbreviations. DSPC, l,2-distearoyl-s -glycerol-3-phosphocholine DSPG, 2,2-distearoyl-5 -glycerol-3[phosphor-rac-(l-glycerol)] CHOL, cholesterol.
For this purpose it is necessaiy to give sufficient contrast to a thin film of the frozen sample, for example, by use of osmium tetroxide. Then the sample can be viewed directly in the TEM (at — 196°C). The adjustment of the temperature to — 196°C produces a very low vapor pressure, especially of water, so that the examination of the probe is possible by preservation of the microstructure despite the high vacuum. A disadvantage of cryo-TEM is the classification of vesicles according to their size. Due to the fluid property of the vesicle dispersion prior to freezing, the thickness of the sample film varies from the center to the outside. Hence the smaller vesicles stay in the center, where the film is thin, while the larger ones remain at the outside margin in the thicker part of the film. In this outer part, the vesicles evade... [Pg.128]

Table 15.1 Comparison of the Sizes and Shapes of Polyaphrons as Determined by Electron Microscopy (Cryo-TEM) with Those of Dispersed CLAs as Determined by Light Scattering... [Pg.671]

Figure 14.8 (Left) Primary sequence of peptide MAXI with /8-hairpin promoted intramolecular folding, leading to the reversible formation of self-assembled /8-sheets. (Right) Cryo-TEM image of self-assembled peptide scaffolds. Scale bar = 200 nm. Reprinted from Schneider et al. (2002). Copyright 2002 American Chemical Society. Figure 14.8 (Left) Primary sequence of peptide MAXI with /8-hairpin promoted intramolecular folding, leading to the reversible formation of self-assembled /8-sheets. (Right) Cryo-TEM image of self-assembled peptide scaffolds. Scale bar = 200 nm. Reprinted from Schneider et al. (2002). Copyright 2002 American Chemical Society.
The invention of the electron microscope in the 1930s by Knoll and Ruska cleared the way for scientists to take an even closer look at vesicles and other colloidal structures [5]. Improving the resolution of the optical microscope roughly by the factor that the optical microscope improved that of the unaided eye, the finer structures of colloidal systems became visible. With the electron microscope, single bilayers can be made visible and the distance between lamellae can be determined. Thus, the structure of a given system can be determined to up to 1/10000000 of a millimeter, which is about the distance of six atoms in a molecule. The most impressive results are obtained with the freeze fracture and cryo-TEM methods [6]. [Pg.255]

Figure 10.10 Transmission electron micrograph of ferritin entrapped in POPC liposomes (palmitoyloleoylphosphatidylcholine). Cryo-TEM micrographs of (a) ferritin-containing POPC liposomes prepared using the reverse-phase evaporation method, followed by a sizing down by extrusion through polycarbonate membranes with 100 nm pore diameters ([POPC] = 6.1 mM) and (b) the vesicle suspension obtained after addition of oleate to pre-formed POPC liposomes ([POPC] = 3 mM, [oleic acid - - oleate] = 3 mM). (Adapted from Berclaz et al, 2001a, b.)... Figure 10.10 Transmission electron micrograph of ferritin entrapped in POPC liposomes (palmitoyloleoylphosphatidylcholine). Cryo-TEM micrographs of (a) ferritin-containing POPC liposomes prepared using the reverse-phase evaporation method, followed by a sizing down by extrusion through polycarbonate membranes with 100 nm pore diameters ([POPC] = 6.1 mM) and (b) the vesicle suspension obtained after addition of oleate to pre-formed POPC liposomes ([POPC] = 3 mM, [oleic acid - - oleate] = 3 mM). (Adapted from Berclaz et al, 2001a, b.)...
Figure 10.12 Number-weighted size distributions as obtained by cryo-TEM (adapted from Berclaz et al, 2001a, b). (a) Distribution for the pre-formed POPC vesicles ([POPC] = 1.9 mM). (b) Distribution for the vesicle suspension obtained upon addition of oleate to pre-formed ferritin-containing POPC vesicles ([POPC] = 0.2 mM [oleic acid -I- oleate] = 5 mM). Empty ( ) and ferritin-containing ( ) vesicles are represented individually in the histogram, (c) Direct comparison of the number-weighted size distribution of the pre-formed POPC vesicles, which contained at least one ferritin molecule ( ) with the number-weighted size distribution of the ferritin-containing vesicles obtained after oleate addition to pre-formed POPC vesicles ( ). Note that the total of all ferritin-containing vesicles was set to 100%. Figure 10.12 Number-weighted size distributions as obtained by cryo-TEM (adapted from Berclaz et al, 2001a, b). (a) Distribution for the pre-formed POPC vesicles ([POPC] = 1.9 mM). (b) Distribution for the vesicle suspension obtained upon addition of oleate to pre-formed ferritin-containing POPC vesicles ([POPC] = 0.2 mM [oleic acid -I- oleate] = 5 mM). Empty ( ) and ferritin-containing ( ) vesicles are represented individually in the histogram, (c) Direct comparison of the number-weighted size distribution of the pre-formed POPC vesicles, which contained at least one ferritin molecule ( ) with the number-weighted size distribution of the ferritin-containing vesicles obtained after oleate addition to pre-formed POPC vesicles ( ). Note that the total of all ferritin-containing vesicles was set to 100%.
Figure 6.4 Cryo-TEM micrographs of some p-lactoglobulin aggregates formed upon heating (a) pH = 2, ionic strength = 0.01 M (b) pH = 2, ionic strength = 0.1 M (c) pH = 7, ionic strength = 0.001 M (d) pH = 7, ionic strength = 0.1 M. Reproduced from Durand et al. (2002) with permission. Figure 6.4 Cryo-TEM micrographs of some p-lactoglobulin aggregates formed upon heating (a) pH = 2, ionic strength = 0.01 M (b) pH = 2, ionic strength = 0.1 M (c) pH = 7, ionic strength = 0.001 M (d) pH = 7, ionic strength = 0.1 M. Reproduced from Durand et al. (2002) with permission.
Borgstrom, J., Piculell, L., Viebke, C., Talmon, Y. (1996). On the structure of aggregated kappa-carrageenan helices a study by cryo-TEM, optical rotation and viscometry. International Journal of Biological Macromolecules, 18, 223-229. [Pg.220]

Gustafsson, J., Arvidson, G., Karlsson, G. and Almgren, M. (1995) Complexes between cationic liposomes and DNA visualized by cryo-TEM. Biochem. Biophys. Acta., 1235, 305-312. [Pg.142]

Left four panels Cryo-TEM micrographs of BGTC/DOPE liposomes, BGTC/DOPE-DNA 290... [Pg.495]

Fig. 17 (a-d) Cryo-TEM images of diblock (sphere-rod) liposomes comprised of liquid-phase lipid nanorods (white arrows) connected to spherical vesicles. The lipid nanorods are stiff cylindrical micelles with an aspect ratio RilOOO. Their diameter equals the thickness of a lipid bilayer ( 4 nm) and their length reaches up to several micrometers, with a persistence length on the order of millimeters, (c) An inset of B, demonstrating the thickness of the nanorod white arrow heads point out a thickness of rj4 nm (approximate bilayer thickness, identical for the spherical vesicle and the nanorods), (d) Schematic of a MVLBisG2/DOPC sphere-rod diblock liposome. Reprinted with permission from [58]. Copyright 2008 American Chemical Society... [Pg.220]

Using optical microscopy and cryo-TEM, we have recently discovered block liposomes, which are liposomes consisting of connected, but distinctly shaped, nanoscale liposome blocks spheres or pears connected to tubes or rods [58, 96, 97]. The key to this discovery is the curvature stabilizing ability of our new, highly charged DL MVLBisG2 (see Sect. 4) [24],... [Pg.221]


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Cryo-TEM imaging

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