Excimer probes

Yang CJ, Jockusch S, Vicens M, Turro NJ, Tan W (2005) Light-switching excimer probes for rapid protein monitoring in complex biological fluids. Proc Natl Acad Sci USA 102 17278-17283... 

Fig. 8 Typical excimer probes utilizing two chelating sites and two fluorophores (20), a flexible central composite receptor site and three fluorophores (21) and a single receptor site with two pendant arms and two fluorophores (22). (a) Na+-induced excimer alignment in 20 and (b) respective spectroscopic response (c) selective probes for Fe3+ (21) and Cu2+ and Ni2+ (22) that show quenching of monomer and excimer emission upon binding. Color code fluorophores in red and atoms responsible for coordination in blue. (Reprinted in part with permission from [83]. Copyright 1995 American Chemical Society)...

Fig. 9 (a) Two examples of excimer probes for anions and (b) response of 23 toward CP in MeCN CHCl3 (95 5 v/v excess of anion indicated). For color code, see Fig. 8. (Reprinted in part with permission from [88]. Copyright 2006 American Chemical Society)...

In a series of papers, Diphant has been used to probe the microviscous properties of various polymer oils, and free volume parameters have been extracted. 4,88 90) In a comparative study of Excimer and TICT probes, it could be shown that the response of these probes is frozen out at lower temperatures, as can be expected from the large reaction volume necessary, whereas the TICT reaction still shows sizable rates at these high-viscosity conditions. (26) Moreover, this study also showed that the free volume fraction measured by the TICT probes is larger than that measured by Excimer probes. 

DMABN suffers from the fact that dual fluorescence is only observable for polar media. Therefore, the pretwisted ester DMPYRBEE has been developed which shows dual fluorescence also in alkane solvents. 9 This probe allowed measurement of nonpolar polymeric siloxane oils and a comparison with the corresponding measurements using an EXCIMER probe. As expected from the decreased reaction volume necessary for the TICT photoreaction, the latter is usable down to much lower temperatures (higher viscosities) and probes a larger fraction of free volume. 26 ... 

Zachariasse, K. A., Vaz, W. L. C., Sotomayor C., and Kiihnle, W. Investigation of human erythrocyte ghost membrane with intramolecular excimer probes, Biochim. Biophys. Acta, 1982, 688, 323-332. 

The objective of this review is to characterize the excimer formation and energy migration processes in aryl vinyl polymers sufficiently well that the excimer probe may be used quantitatively to study polymer structure. One such area of application in which some measure of success has already been achieved is in the analysis of the thermodynamics of multicomponent systems and the kinetics of phase separation. In the future, it is likely that the technique will also prove fruitful in the study of structural order in liquid crystalline polymers. 

The formulation of Eqs. (7.26) and (7.27) was applied to the experimental results of Winnek, Li, and Guillet for pyrene excimer probes on polystyrene, using renormalization group theory for Po(/ ) and coj. The results are in excellent agreement with experiment. 

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