Surface fluorescence microscopy

A wide variety of measurements can now be made on single molecules, including electrical (e.g. scanning tunnelling microscopy), magnetic (e.g. spin resonance), force (e.g. atomic force microscopy), optical (e.g. near-field and far-field fluorescence microscopies) and hybrid teclmiques. This contribution addresses only Arose teclmiques tliat are at least partially optical. Single-particle electrical and force measurements are discussed in tire sections on scanning probe microscopies (B1.19) and surface forces apparatus (B1.20). 

Liebermann T, Knoll W (2003) Parallel multispot detection of target hybridization to surface-bound probe oligonucleotides of different base mismatch by surface-plasmon field-enhanced fluorescence microscopy. Langmuir 9 1567-1572... 

The above discussion provides only a brief overview of how fluorescence techniques can be used to study the interactions of ligands with their receptors. We have focused on the quantitation of the binding parameters and compared the data with that which may be obtained with those from radiolabelled ligand binding studies. The number of applications of fluorescence in the study of neurochemistry and molecular biology is ever increasing. Outside the scope of this review is, for example, the use of fluorescence microscopy to monitor cell surface expression and targeting of receptors or the use of fluorescence probes to monitor ion transport into and out of cells. 

The research group led by Dr. Djilali at the University of Victoria has developed an ex situ experimental technique using fluorescent microscopy to study the liquid water transport mechanisms inside diffusion layers and on their surfaces [239-243]. The diffusion layer is usually placed between two plates (the top plate may or may not have a channel) the liquid water, which is pumped through a syringe pump, flows from the bottom plate through the DL. Fluorescein dye is added to the water for detection with the microscope. 

For the design of mitochondriotropic liposomes, we have used a method, that has been a standard procedure in liposome technology for over 30 years the lipid-mediated anchoring of artificially hydrophobized water-soluble molecules into liposomal membranes (25-28). We have hydrophobized mitochondriotropic TPP cations by conjugating them to long alkyl residues specifically, we have synthesized stearyl TPP (STPP) salts (29). Following liposome preparation in the presence of STPP, the liposomal surface became covalently modified with TPP cations, thereby rendering these liposomes mitochondriotropic as verified in vitro by fluorescence microscopy (30). 

Figure 4. Pea stem material was sequentially extracted with hot 70% ethanol, 0.1 M EDTA and 4% KOH-0.1% NaBH4 to leave xyloglucan-cellulose cell wall ghosts . Binding of fluorescent fucose-binding lectin from Ulex europeus as visualized by fluorescence microscopy shows xyloglucan distributed over the whole wall surface. Photograph courtesy of Dr. T. Hayashi.

Okano et al. [84] measured changes in cytoplasmic Ca2+ concentrations in platelets adhering to HEMA-STY block copolymer (HSB) surfaces by means of fluorescence microscopy combined with a high performance image processor. Comparative studies were also carried out with the HEMA-STY random (HSR) copolymer of poly HEMA and polystyrene. Their results showed that cytoplasmic free calcium levels in platelets that were in contact with the HEMA-STY... 

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