Two-color emissive AIEgens with anti-Kasha property for dual-organelle imaging and phototherapy

Despite the rapid development of probes for targeting single organelle, the construction of robust dual-organelle targeting probes with multicolor emission was rarely reported. Herein, two dual-emissive aggregation-induced emission luminogens(AIEgens)with donor-π-acceptor structures were designed and synthesized, namely QT-1 and QF-2. Both two AIEgens exhibited excitation wavelength-dependence defying the Kasha's rule, and could stain lipid droplets(LDs) and mitochondria in blue and red fluorescence, respectively. Moreover, thanks to the near-infrared emission and abundant reactive oxygen species(ROS) generation efficiency of QT-1, it was chosen as a photodynamic therapy agent to selectively kill cancer cells from normal cells. Upon light irradiation, an obvious decrease of mitochondrial membrane potential(MMP) and serious change of mitochondrial shape in cells were observed, which corresponded to the efficient inhibition of tumor growth in vivo. This work afforded a promising strategy for the construction of multicolor emission by tuning anti-Kasha behaviors and expanding their application in dualorganelle targeting-based phototheranostics.

Enantioselective recognition based on aggregation-induced emission

Chirality is one of the most important features of the nature.The recognition of enantiomers plays significant roles in the field of life science,pharmaceutical analysis and food chemistry.Among various recognition methods,fluorescence spectrometry has attracted much attention of researchers thanks to its high sensitivity and easy operation.Compared with traditional fluorescent probes,chiral molecules with aggregation-induced emission(AIE)have drawn increasing interests due to their huge potential in high-efficiency chemo/biosensors and solid emitters.Chiral AIE luminogens(AIEgens)can not only discriminate two enantiomers with excellent enantioselectivity,but also show general applicability for many chiral analytes,such as chiral acids,amino acids,amines,alcohols.In this review,we mainly summarized the recent development of chiral probes with AIE properties,including chiral tetraphenylethylene(TPE)derivatives,α-cyanostilbene derivatives,Schiff base derivatives and other AIEgens.Their synthetic routes,recognition capabilities and possible working mechanisms were well discussed.It is envisioned that the present review can give some significant guidance for design and synthesis of chiral AIEgens with good enantioselectivity and inspire more readers to join the research of chiral AIE.

“On Water”Effect for Green Click Reaction:Spontaneous Polymerization of Activated Alkyne with“Inert”Aromatic Amine in Aqueous Media

Organic reactions in water have attracted great attention due to their advantages such as unique reaction performance and environmental friendliness.Organic reactions as well as polymerizations in aqueous media have been extensively investigated,and so far,there has been a massive amount of reporting about polymerizations in water.However,reports about click polymerization in water have been rare.Herein,click polymerization of activated alkyne and aromatic amine in aqueous media is developed.The“on water”effect facilitates polymerization in aqueous media better than in organic solvents,and its mechanism is deciphered through experimental data and theoretical calculations.Water participates in the reaction and reduces the energy barrier to some extent.Besides,polymerization makes it possible for aromatic amine with low reactivity to be linked.By using this strategy,polymers with high molecular weights can be obtained in high yields(up to 95.4%).They show good thermal stability and high refractivity.They can be photodegraded.The polymers with tetraphenylethylene moieties show aggregation-induced emission and can be used as materials for generating photopatterns and visualizing agents for specific staining of lysosome in living cells.

Visualization of enantioselective recognition and separation of chiral acids by aggregation-induced emission chiral diamine

Enantioselective recognition and separation are the most important issues in the fields of chemistry,pharmacy,agrochemical,and food science.Here,we developed two optically active diamines showing aggregation-induced emission(AIE)that can discriminate 5 kinds of chiral acids with high enantioselectivity.Especially,a very high fluorescence intensity ratio(IL/ID)of 281 for(±)-Dibenzoyl-D/L-tartaric acid was obtained through the collection of fluorescence change after interaction with chiral AIE-active diamine.By virtue of AIE property and intermolecular acidbase interaction,enantioselective separation was facilely realized by simple filtration of the precipitates formed by chiral AIE luminogen(AIEgen)and one enantiomer in the racemic solution.The chiral HPLC data indicated that the precipitates of AIEgen/chiral acid possessed 82%L-analyte(the enantiomeric excess value was assessed to be 64%ee).Therefore,this method can serve as a simple,convenient,and low-cost tool for chiral detection and separation.