Single molecule probing

Wirth, M.J. and Swinton, D.J., Single-molecule probing of mixed-mode adsorption at a chromatographic interface. Anal. Chem., 70, 5264, 1998. 

In Sec. V we extend the second study to the single-molecule regime using CV as a single-molecule probe [15]. From the observation of biexponential decays of MG fluorescence above and below Tg [12], we assume that polymers with side chains have two sites one is a liquid-like site which causes fast fluorescence decays and the other is a solid-like site which causes slow fluorescence decays. We succeeded in identifying the above assumption at room temperature (23°C) by examining fluorescence properties of individual CV molecules embedded in poly (methylmethacrylate) (PMMA), for which Tg = 114°C [22],... 

V. SINGLE MOLECULES PROBING BIMODAL DOMAIN STRUCTURES IN A POLYMER FILM... 

A. What is Revealed Using Single-Molecule Probes ... 

A single molecule probing is an ultimate method for measuring the properties of the nano-environment at the liquid/liquid interface. A number of studies on single molecule detection in solutions [18-20] and at tbe solid/liquid interface [21-23] were reported, but there were no studies on single molecule detection at the liquid/liquid interface. 

One of the primary compounds that the cell membrane is composed of is DMPC, because of its surface activity caused by a hydrophobic zwitterion. A hydrodynamic model of the DMPC membrane can evaluate the intrinsic viscosity (r]i) of the surfactant monolayer, eliminating the contribution of the viscosity of dodecane and aqueous phases. The T]i values listed in Table 10.1 are about 2-4 times higher than the apparent i. The maximum t]i value, 0.75 Pa s, is comparable to that of a common viscous liquid such as glycerin (0.945 Pa s). This study demonstrated that a single molecule probing method could successfully measure the hydrodynamic properties of the interface. 

The specific features of the interfacial reactions, notably the complexation of metal ions, were reviewed. The dynamic nano-properties of the interface were also discussed from the experimental results of single molecule probing and other dynamic microscopic... 

Exploring Nanostructured Systems with Single-Molecule Probes From Nanoporous Materials to Living Cells... 

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