Electron paramagnetic resonance methodology

Simoes, M. L. (2005). Study of hydrophobic interactions in humic substances and soil components using spectroscopic methodologies. Ph.D. thesis, University of Sao Paulo-USP, Brazil. Singer, L. S. (1959). Synthetic ruby as a secondary standard for the measurement of intensities in electron paramagnetic resonance. J. Appl. Phys. 30,1463-1464. 

The elucidation of PrP structure and function often necessitates the incorporation of biophysical probes. These monitors can be fluorescent dyes which enable one to study protein function both in vivo and in vitro by modem fluorescence methods. The incorporation of nuclear magnetic resonance (NMR) sensitive isotopes or spin labels opens the route to NMR and electron paramagnetic resonance (EPR) methodology. In the following these three methods will be briefly discussed in respect of their application in prion research. 

As discussed further in the following sections, there are other variations of rapid mixing/quench methods in which the enzymatic reaction is terminated by freezing the reaction mixture with liquid isopropane. The frozen sample is then analyzed hy electron paramagnetic resonance (EPR), solid-state NMR, or other spectroscopic techniques such as resonance Raman spectroscopy that can accommodate a solid sample. Perhaps the major limitation for implementation of this methodology is the sensitivity of the spectroscopic method and the requirement for large amounts of enzyme. ... 

Because some of the forms of heme proteins are intrinsically paramagnetic, electron paramagnetic resonance (EPR) has been used extensively to study the stracture and structure-function relations of these proteins. By far the majority of these investigations are done using continuous-wave (cw) EPR at the conventional X-band microwave frequency ( 9.5 GHz), and these cw-EPR studies have formed the basis of many excellent reviews [4-6]. In the last two decennia, the field of EPR spectroscopy has, however, been revolutionized by many technical developments. Indeed, the construction of pulse-EPR spectrometers, die accompanying developments of the pulse-EPR methodology, and the (ongoing) development of... 

Several methodologies based on potentiometric titrations, microelectrophoresis and macroscopic adsorption measnrements have been used in conjunction with Diffuse Reflectance, Raman and Electron Paramagnetic Resonance spectroscopy. Semi-empirical qnantum mechanical calculations, stereochemical considerations and quantum mechanical calculations in the frame of the DFT are followed. The above are then used for developing a quantitative model for the interfacial deposition studied. Details concerning the combined application of these methodologies to obtain the interfacial stmctnre and speciation of the aforementioned species have been reported elsewhere [4-10]. The majority crystal terminations (1 0 1) and (1 0 0) of the anatase nanociystals, comprised in the titania grains, were chosen to exemplify the interfacial stmctures. A titania rich in anatase (Degussa P25) has been used in all cases. 

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