Fluorescence light-scattering

Figure 3. Critical concentration behavior of actin self-assembly. For the top diagram depicting the macroscopic critical concentration curve, one determines the total amount of polymerized actin by methods that measure the sum of addition and release processes occurring at both ends. Examples of such methods are sedimentation, light scattering, fluorescence assays with pyrene-labeled actin, and viscosity measurements. Forthe bottom curves, the polymerization behavior is typically determined by fluorescence assays conducted under conditions where one of the ends is blocked by the presence of molecules such as gelsolin (a barbed-end capping protein) or spectrin-band 4.1 -actin (a complex prepared from erythrocyte membranes, such that only barbed-end growth occurs). Note further that the barbed end (or (+)-end) has a lower critical concentration than the pointed end (or (-)-end). This differential stabilization requires the occurrence of ATP hydrolysis to supply the free energy that drives subunit addition to the (+)-end at the expense of the subunit loss from the (-)-end.

The commonest form of optical spectroscopy measurement involves simple absorption governed by the well-known Beer-Lambert law. However, reflection, light scattering, fluorescence and chemiluminescence methods are also employed in applications relating to process control. 

LAZ Lazzara, G., Milioto, S., and Gradzielski, M., The solubilisation behaviour of some dichloroalkanes in aqueous solutions of PEO-PPO-PEO triblock copolymers A dynamic light scattering, fluorescence spectroscopy, and SANS study, Phys. Chem. 

In a series of papers (24-29) Eicke and co-workers reported results of thorough studies performed on inverse micellar systems involving hydrocarbons such as benzene or isooctane and surfactants such as AY or AOT aerosols. Dielectric, conductance, ultracentrifugation, NMR, light scattering, fluorescence depolarization and photon correlation spectroscopy techniques were used. The main conclusions arrived at are the following ones, as expressed in C29). For water-to-AOT molar ratios smaller than 10, water-in-isooctane systems consist of dispersions of hydrated soap aggre-... 

It is often convenient to express a relation in terms of (= 1/6D ), as in Equation (3.47), although r contains no more information than (it must not be supposed to tell us anything about the motion of an individual molecule). This is because it happens that is also the relaxation time determined by measurements of various phenomena — light-scattering, fluorescence-depolarisation, and pulsed nmr — which are important in the determination of diffusion coefficients (Section S.4.2.2). 

Proteins separated by chromatography using any of these techniques can be detected using UV spectroscopy, refractive index, evaporative light scattering, fluorescence or mass spectrometry detection. 

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