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A series of π conjugated naphthalimide derivatives having an imide group as an acceptor conjugated with a methoxy arylethynyl or a methoxyphenyl triazole as a donor were prepared by Sonogashira coupling or "click" chemistry. Their photophysical properties were investigated by steady state and time resolved fluorescence spectroscopy and modelled by TD-DFT calculations. Compound Naphth-AlkyneOMe has a high fluorescence quantum yield and displays efficient photoinduced charge transfer in solution as well as in the powder state. Compound Naphth-TriazoleOMe exhibits a very high Stokes shift and its fluorescence quantum yield is low, which can be rationalized by theoretical calculations.

A series of fluorescent sensor molecules based on a phosphane sulfide derivative that is soluble in an organoaqueous solvent were designed and synthesized. The structure of the fluorophore has been optimized in order to have the best compromise in terms of solubility and photophysical properties. The obtained properties are in full agreement with quantum chemical calculations. A fluorescent molecular sensor containing one polyoxoethylene group has been synthesized and an efficient quenching upon mercury complexation has been observed. Finally, this sensing molecule has been introduced in a microfluidic chip in which fluorescence detection has been integrated. An efficient fluorescence response was observed upon mercury addition.

The photophysical properties of the new pyridin-2'-yl-1,2,3-triazole chromophore have been investigated. Spectroscopic experiments and molecular modelling have provided evidence for a photoinduced charge transfer occurring from the triazole group to the pyridine ring. Hepta- and tetrachromophoric systems have been synthesized by covalently linking seven or four chromophores of this kind, respectively, to a beta-cyclodextrin and a calix[4]arene. They exhibit different fluorescence spectra, decays and quantum yields. Special attention has been paid to the binding of cadmium and zinc ions and to the resulting photophysical effects which are various and very different for the grafted beta-cyclodextrin and calix[4]arene systems.

Three self-assembled photonic dyads comprising a zinc porphyrin donor and a free base acceptor have been studied by time-resolved fluorescence spectroscopy. The driving force of the assembly is the site selective binding of an imidazole connected to a free base porphyrin. Three spacers have been incorporated between the imidazole connector and the free base porphyrin, providing three different distances separating the donor and the acceptor. The high efficiencies and the rates of energy transfer in the set of dyads is consistent with the Forster energy transfer mechanism. Evidence for Forster back transfer has been obtained, and its efficiency and rate have been quantitatively evaluated for the first time.

The photophysical properties of calixarenes bearing two and four dansyl derivatives (Calix-DANS2 and Calix-DANS4) were investigated in a CH(3)CN/H(2)O mixture (60 : 40 v/v). The carboxydansyl (DANS1) was used as a reference compound. The pH titration of DANS1 permits determination of two pK(A) values (2.4 and 6.3). The charge-transfer character of this type of fluorophore is discussed. The protonated dansyl group LH(2)(+) undergoes photoinduced proton transfer. The photophysical characterization (absorption spectra, emission spectra, quantum yield and fluorescence decays) of Calix-DANS2 and Calix-DANS4 showed that nonradiative energy transfer occurs from a dansyl fluorophore in the basic form to another one in the neutral form. The transfer efficiencies are 0.1 and 0.5 for Calix-DANS2 and Calix-DANS4, respectively. Fluorescence data analysis allowed us to determine the fractions of dansyl fluorophores in the basic and neutral forms.