Transient studies on intramicellar excimer formation. A useful probe of the host micelle

Dynamics of Fluorescence Quenching of Pyrene in Novel Micelles of the Zwitterionic Betaine SurfactantN-(3-Dodecyloxy-2-hydroxypropyl)-N,N-dimethylglycine

“…This allows us to distinguish among the following three situations: (i) The distribution of the quencher is "frozen" on the time scale of the fluorescence, that is, the residence time of the quencher in the micelles is much longer than the probe fluorescence lifetime. Such case is found to be in accordance with pyrene excimer formation (13,14) or the quenching of pyrene fluorescence by cetylpyridinium ions (15,17).…”

“…1 and 2), whose regression analysis is given by Eqs. [13] and [14]: log k q ϭ 3.4111 Ϫ 0.9528 log N ͑r ϭ 0.9896, for cationic DHDG micelle), [13] log k q ϭ 2.7076 Ϫ 0.9649 log N ͑r ϭ 0.9890, for zwitterionic DHDG micelle). [14] From these equations, the following conclusion can be made: (i) Added salt (in the range studied) induces DHDG micellar Due to their hydrophilicity, iodide ions are initially outside micelles, but must approach excited pyrene molecules solubilized in the micelles before quenching can take place.…”

“…the pyrene excimer is formed. The analysis of decay curves will give n, which is available for calculating N (13,14,20):…”

The Time-Resolved Fluorescence Quenching Method for the Study of Micellar Systems and Microemulsions : Principle and Limitations of the Method

“…It bas been shown (13] that in this case the expressions for A2, A3 and A4 are: (2) The same expressions were established to interpret the results ofintramicellar photoredox reaction (14] and can be deduced from the decay equation given by Infelta et a1. [8] and by Tachiya [9] assuming that the quencher molecules are exclusively solubilized into the micelles.…”

Fluorescence Probes of Micellar Systems—An Overview

“…69 If the additive is completely incorporated into the cationic micelles, this concentration corresponds to an average of 10 hexanoates per micelle. Above this additive concentration, the experimentally derived values of IT significantly decrease, while kE slightly decreases indicating changes in the host micelle.…”