The triazine-based bisbinaphthyl crown ethers oxacalix[2]arene[2]bisbinaphthes R-1, R-2, R-3 and S-1, S-2, S-3 were synthesized. The interactions of these compounds with various α-aminocarboxylic acid anions were studied. The crown ethers were found to carry out highly enantioselective fluorescent recognition of α-aminocarboxylic acid anions. It is observed that within a certain concentration range, one enantiomer of the chiral α-aminocarboxylic acid anions can increase the fluorescence intensity of the crown ethers by fivefold to sixfold, whereas the other enantiomer scarcely enhances the fluorescence. Such unusually high enantioselective responses make these crown ethers very attractive as fluorescent sensors in determining the enantiomeric composition of α-aminocarboxylic acid anions.

chitosan oligosaccharide functionalized silver nanoparticles with synergistic bacterial activity were constructed as a multivalent inhibitor of bacteria. placing the chitosan oligosaccharide on silver nanoparticles can dramatically enhance the adsorption to the bacterial membrane via multivalent binding. the multicomponent nanostructures can cooperate synergistically against gram-positive and gram-negative bacteria. the antibacterial activity was increased via orthogonal array design to optimize the synthesis condition. The synergistic bacterial activity was confirmed by fractional inhibitory concentration and zone of inhibition test. through studies of antimicrobial action mechanism, it was found that the nanocomposites interacted with the bacteria by binding to Mg 2+ ions of the bacterial surface. then, the nanocomposites disrupted bacterial membrane by increasing the permeability of the outer membrane, resulting in leakage of cytoplasm. this strategy of chitosan oligosaccharide modification can increase the antibacterial activity of silver nanoparticles and accelerate wound healing at the same time. the nanomaterial without cytotoxicity has promising applications in bacteria-infected wound healing therapy. Human health has been threatened with abuse of antibiotics and the appearance of multiple drug-resistant bacteria 1,2. In the European Union, the number of deaths attributable to antibiotic-resistant bacteria is about 25,000 each year 3. Therefore, it is crucial to design and develop new antimicrobial materials with high antibacterial activity and low resistance in the field of biomedicine. Silver nanoparticles (AgNPs) with small size and large specific surface area have a stronger antibacterial effect against different bacteria, virus, and fungi 4-6. AgNPs can contact with bacterial cell membranes, penetrate into the cytoplasm, and then inactivate essential respiratory enzymes and proteins, leading to bacterial death 7,8. However, these antibacterial action of AgNPs is often dependent on high concentration since their physical collision with bacterial surface is random 9. For enhancing interaction of AgNPs and the bacteria, cationic polymers-stabilized AgNPs were designed to bind to the negatively charged cell surfaces of the bacteria by electrostatic interaction 10,11. However, the toxicity of cationic polymers obstructed their biomedicine application. Then, to improve their biocompatibility, collagen-stabilized AgNPs were prepared by a photochemical method 12. However, it was found that this AgNPs showed a weaker antibacterial property, comparing with small molecules-stabilized AgNPs (eg. lysine and citrate). Chitosan oligosaccharide (COS), which is a cationic, non-immunogenic, biocompatible and an FDA-recognized mucoadhesive polymer 13 , with low molecular and good water-solubility is the positively charged alkaline-amino-oligosaccharide. Several biological activities of COS, such as hemostasis, antibacterial activity and anti-inflammatory effects, have been extensively studied in biomaterials field 14. ...

The terpyridine anthracene ligand was synthesized and characterized. is a ratiometric fluorescent probe for Cd(2+) with a recognition mechanism based on intramolecular charge transfer (ICT). An complex was isolated, and its structure was established using single-crystal XRD. The complex was able to serve as a novel reversible chemosensing ensemble to allow ratiometric response to pyrophosphate (PPi) in aqueous media. Moreover, the fluorescence imaging in living cells from these two emission channels suggested that was a ratiometric probe for Cd(2+), and the in situ generated complex was also a ratiometric ensemble for PPi detection in living cells.

Minimal AIEEgens containing only a single ring were synthesized through a facile biocatalysis procedure and were successfully utilized in the imaging of mitochondria.

We presented a novel approach for pyrophosphate (PPi) sensing. Two tetraphenylethene (TPE)-functionalised pyridine salts (TPM and TPH) were designed and synthesized. Both of them exhibited weak emission in the solution state that originates from intramolecular charge transfer (ICT) from TPE to the pyridine; the addition of PPi into the TPM aqueous solution would enhance the fluorescence intensity, which eliminates the emission quenching effect of the iodide ion by the formation of PPi-sensor nanoparticles. The detection limit of TPM was determined to be as low as 133 nM. Meanwhile, a thin solid film of TPM that could detect PPi rapidly was conveniently prepared.

A novel BINOL-based ratiometric fluorescent sensor (R2) is presented, which can selectively respond to Zn(2+) over Cd(2+) and other metal ions with fluorescence enhancement in aqueous solution. The R2 was successfully applied in the imaging of Zn(2+) in living cells. Additionally, the in situ generated R2-Zn(II) ensemble could further serve as a probe to distinguish histidine from other amino acids via a displacement mode.

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An in situ generated BINOL-DPA-Zn(ii) complex is presented as a chemo-sensing ensemble for the recognition of phosphate-based molecules. The ensemble showed high sensitivity and selectivity for pyrophosphates (PPi), and it could be successfully applied in imaging PPi in living cells. Notably, the ensemble exhibited a very low detection limit (95 nM) for PPi and could realize the real time detection of PPi by the naked eye through precipitate experiments. The ensemble also showed good selectivity towards ATP, and the selectivity coefficient for PPi and ATP was calculated to be 4.1/2.8.