Solutions, images membranes

Selected entries from Methods in Enzymology [vol, page(s)] Chelation, 238, 74, 76, 297 buffers [for analysis of exocytosis, 221, 132 preparation, 219, 186 modulation of cytosolic buffering capacity with quin2, 221, 159] fluorescence assay, 240, 724-725, 740-742 fluorescence imaging, 225, 531 238, 303-304, 322-325, 334-335 free intracellular levels after bacterial invasion, 236, 482-489 free calcium in solutions for membrane fusion analysis, calculation and control, 221, 149 homeostasis mechanisms, 238, 80 hormonal elevation, 238, 79 inositol phosphate effect on release, 238, 207 determination of cytosolic levels [computer methods, 238, 73-75 with fura-2, 238, 73, 146 with indo-1, 238, 298, 316-317 with quin-2, 238, 297] hormone effects, 238, 79 ionomycin effects, 238, 79 membrane depolarization effects,... 

Tip collection mode is the simplest SECM mode for imaging membranes, and the first to be employed for this purpose. The membrane separates a donor solution, which contains a redox species, from a receptor solution in which the redox species is absent. The SECM tip current arises solely from the transport of redox species across the membrane—a large tip current indicates a localized region in which the spatial flux in the membrane is large, often due to a discrete pore. No... 

Figure 2.12 TEM images of PBMA membranes with added ZnAl-MA-LDH prepared by (a) emulsion polymerization and (b) solution polymerization in l-methyl-2-pyrolidone (NMP) or (c) mixture of dimethylformamide (DMF) and formamide (FA) (d) exfoliated LDH nanoparticles in the sample prepared by solution polymerization in DMF and FA mixed solution - image taken at higher magnification. Reproduced with permission from reference 144.

Thin film nanostructures of the III-VI compound In2Se3 were obtained inside the pores (200 nm) of commercial polycarbonate membrane by automated ECALE methodology at room temperature [157], Buffered solutions with millimolar concentrations of In2(S04)3 (pH 3.0) and Se02 (pH 5.5) were used. The atomic ratio of Se/In in the deposited films was found to be 3/2. Band gaps from FTIR reflection absorption measurements were found to be 1.73 eV. AFM imaging showed that the deposits consist of 100 nm crystallites. 

FIG. 14 Constant height mode gray-scale image of a 5/xm-diameter pore in a polycarbonate membrane obtained with a 3 fim pipette tip. The filling DCE solution contained 10 mM TBATPBCl. The aqueous phase contained 0.4mM TEACl + lOmM LiCl. The scale bar corresponds to 10/xm. The tip scan speed was 10/xm/s. (Reprinted with permission from Ref. 30. Copyright 1998 American Chemical Society.)... 

Trimethylaminodiphenylhexatriene chloride (TMADPH Fig. 7.45) is a fluorescent quaternary ammonium molecule that appears to permeate cell membranes [595]. TMADPH fluoresces only when it is in the bilayer, and not when it is dissolved in water. Therefore, its location in cells can be readily followed with an imaging fluorescence microscope. One second after TMADPH is added to the extracellular solution bathing HeLa cell types, the charged molecule fully equilibrates between the external buffer and the extracellular (outer) leaflet bilayer. Washing the cells for one minute removes >95% of the TMADPH from the outer leaflet. If the cells are equilibrated with TMADPH for 10 min at 37°C, followed by a one-minute wash that removed the TMADPH from the outer leaflet, the fluorescent molecule is... 

Fig. 9 Surface modification of cells with ssDNA-PEG-lipid. (a) Real-time monitoring of PEG-lipid incorporation into a supported lipid membrane by SPR. (r) A suspension of small unilamellar vesicles (SUV) of egg yolk lecithin (70 pg/mL) was applied to a CH3-SAM surface. A PEG-lipid solution (100 pg/mL) was then applied, (ii) Three types of PEG-lipids were compared PEG-DMPE (C14), PEG-DPPE (C16), and PEG-DSPE (C18) with acyl chains of 14, 16, and 18 carbons, respectively, (b) Confocal laser scanning microscopic image of an CCRF-CEM cell displays immobilized FITC-oligo(dA)2o hybridized to membrane-incorporated oligo(dT)20-PEG-lipid. (c) SPR sensorigrams of interaction between oligo(dA)2o-urokinase and the oligo (dT)2o-PEG-lipid incorporated into the cell surface, (i) BSA solution was applied to block nonspecific sites on the oligo(dT)20-incorporated substrate, (ii) Oligo(dA)20-urokinase (solid line) or oligo(dT)20-urokinase (dotted line) was applied...

Fig. 10 Confocal laser scanning microscope images of islets with urokinase (UK) immobilized on the membrane. The green fluorescence indicates positive immunostaining for UK. (a) Islets were modified with oligo(dT)2o-PEG-lipid (C16) or (b) oligo(dT)2o-PEG-lipid (C18) then, oligo (dA)2o-UK was added to the media, (c) Unmodified islets with (left) and without (right) oligo (dT)20-PEG-lipids added to the solution. Insets. Bright field images. Scale bars 100 pm...

The protein A layer was incubated for 1 h to be cross-linked by glutaraldehyde, which was followed by transfer to a compartment containing ultrapure water for rinsing. The protein A molecular membrane was then transferred onto the surface of an HOPG plate by the horizontal method. The molecular imaging of the preparation was obtained by AFM in solution. 

Stop the reaction by pouring off and discarding the staining solution, and rinse the membrane briefly m two changes of distilled water. The membrane can then be dried between filter paper and, once diy, can be photographed for a permanent record. The image will remain on the blot if it is stored in the dark, but otherwise will fade with time... 

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