Total fluorescence signal, adsorbed

Fluorescently labeled quat materials have been used to determine the total silicone uptake of the fibers indirectly. The decline of the fluorescence signal of the finishing liquor is equivalent to the amount of silicone adsorbed on the fiber surface and dififiised into the interior of the fiber (Scheme 2). 

Further structural information has been derived from the recent use of optical spectroscopy as a probe of structure at the L-L interface the two general approaches pursued are (i) total internal reflectance (TIR) fluorescence spectroscopy of adsorbed solute species and (ii) nonlinear spectroscopic methods to generate interface-sensitive spectra of the solvent molecules in the interfacial region. The former approach uses the polarization of the emitted signal, from an s-polarized excitation, to determine the effective dimensionality of the interface. The anisotropy of the fluorescent response from an interface that is flat on the length-scale of the adsorbed probe ( lnm) is [33]... 

The same principles of total internal reflection can also be used to excite fluorescent chromophores attached to the polymer chain (9). The emitted fluorescence can be used to estimate the surface excess. In addition to subtracting the background signal, fluorescence quenching in the adsorbed layers may also have to be considered while estimating the adsorbed amount. The disadvantage of this technique is that the polymer chains have to be labeled with fluorescence molecules and that might influence the adsorption process. 

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