Biophysical Applications

An interesting concept to achieve the latter regime i.e. to obtain increased radiative rates, has been suggested by Enderlein. As depicted in figure 15, a dye molecule is fixed in the center of a metallic sphere. As it is away from the metal surface, energy transfer is less important, while the increase in field strength increases the molecular 

Two photrai fluorescence can also be enhanced by some orders of magnitude.  

In those cases, the ina-eased two photon absorption due to the field enhancement effect clearly outweighs the effects of fluorescence quenching. However, also these experiments had been carried out on submonolayer metallic films. Peleg et al. showed a decreased two photon fluorescence signal frcnn fluorophores close to single gold nanoparticles.  

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Modem understanding of the hydrophobic effect attributes it primarily to a decrease in the number of hydrogen bonds that can be achieved by the water molecules when they are near a nonpolar surface. This view is confirmed by computer simulations of nonpolar solutes in water [15]. To a first approximation, the magnimde of the free energy associated with the nonpolar contribution can thus be considered to be proportional to the number of solvent molecules in the first solvation shell. This idea leads to a convenient and attractive approximation that is used extensively in biophysical applications [9,16-18]. It consists in assuming that the nonpolar free energy contribution is directly related to the SASA [9],... 

The simplicity and accuracy of such models for the hydration of small molecule solutes has been surprising, as well as extensively scrutinized (Pratt, 2002). In the context of biophysical applications, these models can be viewed as providing a basis for considering specific physical mechanisms that contribute to hydrophobicity in more complex systems. For example, a natural explanation of entropy convergence in the temperature dependence of hydrophobic hydration and the heat denaturation of proteins emerges from this model (Garde et al., 1996), as well as a mechanistic description of the pressure dependence of hydrophobic... 

Selvin PR (2002) Principles and biophysical applications of lanthanide-based probes. Annu Rev Biophys Biomol Struct 31 275-302... 

This description of the nonpolar contribution to the free energy has been extensively used in biophysical applications [72-75]. In practice, the surface tension 7V is usually obtained from experimental transfer free energies of small organic molecules... 

Electron Spin Resonance, Biochemical and Biophysical Application of (Swartz... 

In an biophysical application of organometaliic photochemistry, photolysis of [Co(CN)5(CHjC02)] is employed to trap nitroxides ... 

Many of the experimental approaches to study protein structure by solid-state MAS NMR have been devised relatively recently. Not surprisingly, the number of biophysical applications using such methods is still limited. Nevertheless, we will present in Chapter 3 different areas of research where MAS-based solid-state NMR has already been applied and which may pave the way for future applications. We also refer the interested reader to... 

Selvin, P. R., Principle, Biophysical Applications of Lanthanide based Probes, Anna. Rev. Biophys. Biomol. Struct. 2002, 31, 275 302. 

This chapter reviews several techniques which combine the use of laser microbeams with antibodies to study molecular and cellular biology. An overview of the basic properties of lasers and their integration with microscopes and computers is provided. Biophysical applications, such as fluorescence recovery after photobleaching to measure molecular mobility and fluorescence resonance energy transfer to measure molecular distances, as well as ablative applications for the selective inactivation of proteins or the selective killing of cells are described. Other techniques, such as optical trapping, that do not rely on the interaction of the laser with the targeting antibody, are also discussed. 

Swartz, H. M., and S. M. Swartz. Biochemical and biophysical applications of electron-spin resonance. Methods Biochem. Anal. 29 (1983), 207-323. 

In Volume 3, our Section Editors have assembled 12 contributions in six sections. Topics covered include Simulation Methodologies (Carlos Simmerling), Biological and Biophysical Applications (Heather Carlson), Chemical Education (Theresa Zielinski), Materials and Polymers (Jeffry Madura), Quantum Chemistry (T. Daniel Crawford), and Emerging Technologies (Wendy Cornell). With Volume 3, we extend the practice of cumulative indexing of both the current and past editions in order to provide easy identification of past reports and topics. 

Frank-Kamenetskii, M.D., Vologodskii, A.V., 1981. Topological aspects of polymer physics theory and its biophysical applications. Sov. Phys. Usp. 24 679-696. 

E. Betzig, A. Lewis, A. Harootunian, M. Isaacson, and E. Kratschmer, Near-Field Scanning Optical Microscopy (NSOM) -Development and Biophysical Applications, Biophys. J. 49, 269 (1986)... 

An overview of high-resolution solid state NMR applications to polypeptides and membrane proteins has been presented by Luca et a/. The importance of the MAS based techniques at ultrahigh magnetic fields for the studies of insoluble or noncrystalline molecules at the atomic level is highlighted. Recently developed NMR methods suitable for the study of multiply or uniformly [ C, N]-labelled polypeptides and proteins are discussed. In addition, latest biophysical applications are reviewed. 

Betzig. E. Lewis, A. Harootunian. A. Isaacson, M. Kratschmer, E. Near-field scanning optical microscopy (NSOM)—Development and biophysical applications. Biophys. J. 1986. 49 (1). 269-279. 

As mentioned previously the amount of paramagnetic species in a sample is of interest in biophysical applications [3]. The radical yields determined by ESR have also been measured to help elucidate the radiation chemistry of the solid state and in several other applications referred to in Table 9.1. The concentration of radicals at... 

Thrae ate numaous biophysical applications for long-life-time anisotropy probes. These include studies of all types of macromolecular assemblies. The use of long-lifetime probes in biochemistry is just banning. We have chosen to show just three representative applications studies of DMA dynamics, measurement of domam-to-domain mo-... 

This mode is a flexible method for obtaining heterogeneous kinetic information about nonelectrochemical processes. It has been applied to, amongst other systems, adsorption/desorption, solubility, and partition equilibria as well as biophysical applications such as lateral proton transport in models of cell membranes [51]. 

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