Tumortherapeutika Pyridiniumsubstituierte Tetraphenylethylen‐Salze können Autophagie induzieren und gleichzeitig den Autophagieflux hemmen. R. Zhao, D. Zhang et al. berichten in ihrem Forschungsartikel auf S. 10128, wie diese Ergebnisse neue Funktionalitäten für AIEgene aufzeigen.

Herein, a new fluorescence turn-on chemosensor 2-(4-(1,2,2-triphenylvinyl)phenoxy)acetic acid (TPE-COOH) specific for Al(3+) was presented by combining the aggregation-induced-emission (AIE) effect of tertaphenylethylene and the complexation capability of carboxyl. The introduction of carboxylic group provides the probe with good water-solubility which is important for analyzing biological samples. The recognition toward Al(3+) induced the molecular aggregation and activated the blue fluorescence of the TPE core. The high selectivity of the probe was demonstrated by discriminating Al(3+) over a variety of metal ions in a complex mixture. A detection limit down to 21.6 nM was determined for Al(3+) quantitation. Furthermore, benefiting from its good water solubility and biocompatibility, imaging detection and real-time monitoring of Al(3+) in living HeLa cells were successfully achieved. The AIE effect of the probe enables high signal-to-noise ratio for bioimaging even without multiple washing steps. These superiorities make this probe a great potential for the functional study and analysis of Al(3+) in complex biosystems.

The construction of molecularly imprinted polymers on magnetic nanoparticles gives access to smart materials with dual functions of target recognition and magnetic separation. In this study, the superparamagnetic surface-molecularly imprinted nanoparticles were prepared via surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization using ofloxacin (OFX) as template for the separation of fluoroquinolones (FQs). Benefiting from the living/controlled nature of RAFT reaction, distinct core-shell structure was successfully constructed. The highly uniform nanoscale MIP layer was homogeneously grafted on the surface of RAFT agent TTCA modified Fe3O4@SiO2 nanoparticles, which favors the fast mass transfer and rapid binding kinetics. The target binding assays demonstrate the desirable adsorption capacity and imprinting efficiency of Fe3O4@MIP. High selectivity of Fe3O4@MIP toward FQs (ofloxacin, pefloxacin, enrofloxacin, norfloxacin, and gatifloxacin) was exhibited by competitive binding assay. The Fe3O4@MIP nanoparticles were successfully applied for the direct enrichment of five FQs from human urine. The spiked human urine samples were determined and the recoveries ranging from 83.1 to 103.1% were obtained with RSD of 0.8-8.2% (n = 3). This work provides a versatile approach for the fabrication of well-defined MIP on nanomaterials for the analysis of complicated biosystems.

The cell selectivity, subcellular localization and cytotoxicity can be tuned by the counter anions of nanoparticles assembled from pyridinium-substituted tetraphenylethylene.

Metal–peptide interactions provide plentiful resource and design principles for developing functional biomaterials and smart sensors. Pb2+, as a borderline metal ion, has versatile coordination modes. The interference from competing metal ions and endogenous chelating species greatly challenges Pb2+ analysis, especially in complicated living biosystems. Herein, a biomimetic peptide-based fluorescent sensor GSSH-2TPE was developed, starting from the structure of a naturally occurring peptide glutathione. Lewis acid–base theory was employed to guide the molecular design and tune the affinity and selectivity of the targeting performance. The integration of peptide recognition and aggregation-induced emission effect provides desirable sensing features, including specific turn-on response to Pb2+ over 18 different metal ions, rapid binding, and signal output, as well as high sensitivity with a detection limit of 1.5 nM. Mechanism investigation demonstrated the balance between the chelating groups, and the molecular configuration of the sensor contributes to the high selectivity toward Pb2+ complexation. The ion-induced supramolecular assembly lights up the bright fluorescence. The ability to image Pb2+ in living cells was exhibited with minimal interference from endogenous biothiols, no background fluorescence, and good biocompatibility. With good cell permeability, GSSH-2TPE can monitor changes in Pb2+ levels and biodistribution and thus predict possible damage pathways. Such metal–peptide interaction-based sensing systems offer tailorable platforms for designing bioanalytical tools and show great potential for studying the cell biology of metal ions in living biosystems.

The rate constants for the reaction of SO3 with H2O in He and in N2 were measured at total pressures from 1–10 Torr in a flow tube at room temperature. The concentration of SO3 was monitored by photofragment emission produced by 147 nm excitation. Dependencies of apparent reaction rates on wall conditions and reaction tube sizes were investigated. At total He pressures of 1–10 Torr, a value of (5.7±0.9)×10−15 cm3 /s was obtained for the upper limit of the homogeneous gas phase reaction rate constant. This rate value is more than two orders of magnitude lower than the previously published value, but it is consistent with the theoretical calculation provided in this paper.

Smart and versatile nanostructures have demonstrated their effectiveness for biomolecule analysis and show great potential in digging insights into the structural/functional relationships. Herein, a nanoscale molecular self-assembly was constructed for probing the site-specific recognition and conformational changes of human serum albumin (HSA) with tunable size and emission. A tetraphenylethylene derivative TPE-red-COOH was used as the building block for tailoring fluorescence-silent nanoparticles. The highly specific and sensitive response to HSA was witnessed by the fast turn-on of the red fluorescence and simultaneous disassembly of the nanostructures, whereas various endogenous biomolecules cannot induce such response. The mechanism investigation indicates that the combination of multiple noncovalent interactions is the driving force for disassembling and trapping TPE-red-COOH into HSA. The resultant restriction of intramolecular rotation of TPE-red-COOH in the hydrophobic cavity of HSA induces the significant red emission. By using the fluorescence activatable nanosensor as the structural indicator, the stepwise conformational transitions of HSA during denaturing and the partial refolding of subdomain IIA of HSA were facilely visualized. Benefiting from its activatable signaling, sensitivity, and simplicity, such molecular assembly provides a kind of soft nanomaterial for site-specific biomolecule probing and conformational transition detection concerning their structure, function, and biomedical characteristics.

A peptide-guided prodrug incorporating a tumor-specific peptide, doxorubicin, and a pH-sensitive hydrazone bridge was developed for targeted ablation of cancer cells with minimal side cytotoxicity.