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A glutamide gelator, 1, was synthesized,and a weakemission enhancement was observed during its gelation. In addition, 1could be an excellent scaffold for successfully embeddingan energy acceptor, 2, into its aggregate to obtain highlyefficient energy transfer. An amplification of the emission enhancementwas observed in the two-component gels compared to that of the neatgel of 1during gel formation. For example, 1induced only a 2.5-fold increase in emission intensity, whereasa 23-fold enhanced emission could be observed in the two-componentgel with only 1.6 mol % 2. Furthermore, two-componentgels had an excited proton response. In systems with low acceptorconcentrations, the hot solution red-shifted the fluorescence fromblue to yellow upon the addition of a proton, which continuously blue-shiftedwith decreasing temperature to form the gel given that the bindingof the gelator to the proton is weakened during coassembly. Moreover,the casting film formed by the two-component wet gel had an excellentresponse to volatile acids such as hydrochloric acid, trifluoroaceticacid, and so on and could be reversibly recovered by exposure to NH3. [ABSTRACT FROM AUTHOR]

Abstract: We report on the synthesis and self-assembly of a new discotic organogelator based on π-conjugated triphenylbenzene with three peripheral chiral substituents. It is found that the introduction of chiral groups to the C 3-symmetric molecule led to a hexagonal columnar chiral stacking of the molecules in a clockwise direction in the organogel fibers. And the fluorescent emission of the gel decreased significantly compared to the monomer state at the same concentration, as a result of the aggregation of the nonplanar triphenylbenzene core in the gel phase. [Copyright &y& Elsevier]

Nanofibers based on phenanthroimidazole derivatives PCC, PDC, and PSC were fabricated by organogelation processes, and their fluorescence sensory properties towards acid were investigated. It was found that the emission of PCC in the nanofiber-based film could be quenched significantly upon exposure to gaseous TFA due to the formation of protonated PCC, in which ICT (intramolecular charge transfer) would occur. On the other hand, TFA vapor led to the emitting colors of PDC and PSC in the nanofiber-based films to turn to yellow and green from sky blue and blue, respectively. Additionally, we found that the decay times of PCC were 0.1 s and 1.9 s in probing the saturated vapor of TFA in nanofiber-based film and in spin-coated film, respectively. The results suggested that the high surface-to-volume ratio and large interspace in the nanofiber-based networks favored the enhanced adsorption, accumulation, and diffusion of gaseous molecules, resulting in such a high performance. [ABSTRACT FROM AUTHOR]