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Bacterial biofilms often lead to persistent infections because they provide a protective barrier and reproductive microenvironment for bacteria. Biofilms reduce the therapeutic effects of antibiotics and can easily lead to the emergence of multidrug‐resistant bacteria. Therefore, development of new materials for antibiofilm with synergistic effects is crucial. In this study, positively charged near‐infrared‐responsive nanoparticles (TDPPB) are synthesized to control the release and delivery of nitric oxide (NO) gas. A combination of NO and photothermal therapy (PTT) is used to enhance the antibiofilm performance of TDPPB. The positive charge of TDPPB induces the nanoparticles to adhere to the surface of the bacteria. Through 808 nm laser irradiation, the local high temperature triggers the efficient release of NO from the NO donor (BNN 6) in TDPPB. TDPPB integrates the release of NO, and PTT presents good antibiofilm activity against MRSA and Escherichia coli (E. coli) biofilms. TDPPB demonstrates excellent biosafety both in vivo and in vitro, shows good antibiofilm properties in biofilm‐infected mice, and promotes the healing of surface‐infected sites in vivo. Because of these advantages, TDPPB can be used as a potential therapeutic agent against biofilm infections in the biomedical field. [ABSTRACT FROM AUTHOR]

Herein, two excited-state intramolecular proton transfer (ESIPT)-capable α-cyanostilbene luminogens were synthesized by Schiff base reaction of salicylaldehyde-like α-cyanostilbene candidate with 1-naphthylamine and 3-biphenylamine, respectively. We systematically analyzed their photophysical properties compared with their analogue, and demonstrated that their fluorescence behaviors could be elaborately modulated by different aromatic substitutions tethered to H-acceptor (CH = N). In virtue of the outstanding solid fluorescence, the 3-biphenylamine-decorated fluorophore was applied for monitoring Cu2+/Fe3+ qualitatively on the TLC-based test strip in real time and sensing Cu2+/Fe3+ quantitatively in the THF/H2O medium (fw = 90%, pH = 7.4). When the probe chelated with Cu2+/Fe3+, similar “turn-off” fluorescence signal outputs were triggered. From the fluorescence titration experiments, the detection limits were evaluated as 7.97 × 10− 8 M for Cu2+ and 8.24 × 10− 8 M for Fe3+, and the binding constant (Kα) values of the complexes were found to be 7.80 × 104 M-1 for Cu2+ and 9.06 × 104 M-1 for Fe3+. Job’s plots indicated that probe complexed with Cu2+/Fe3+ in a 2:1 binding stoichiometry ratio. Furthermore, the probe was used to accurately quantify the Fe3+ spiked in real water specimens. This study offered a new perspective to construct ESIPT-capable α-cyanostilbene luminogen as the potential luminescent probe. [ABSTRACT FROM AUTHOR]

Here, three Schiff bases 3a-c, differing by the substitutions (–H, –Cl, and –N(CH3)2) on the phenyl ring, have been designed and synthesized via the reaction of ortho-aminophenol with benzaldehyde, 2,4-dichlorobenzaldehyde and para-dimethylamine benzaldehyde in 1:1 molar ratio with favourable yields of 89–92%, respectively. Their structural characterizations were studied by FT-IR, NMR, MALDI-MS and elemental analysis. The fluorescence behaviours of compounds 3a and 3b exhibited a severe aggregation caused quenching (ACQ) effect in EtOH/water system. On the contrary, compound 3c had an obvious J-aggregation induced emission (AIE) feature in EtOH/water mixture (v/v = 1:1), and exhibited excellent sensitivity and anti-interference towards Cu2+ with the limit of detection (LOD) of 1.35 × 10–8 M. Job's plot analysis and MS spectroscopic study revealed the 2:1 complexation of probe 3c and Cu2+. In addition, probe 3c was successfully applied to the determination of Cu2+ in real aqueous samples. [ABSTRACT FROM AUTHOR]

We designed and synthesized a new Schiff base probe, which incorporated the salicylaldehyde-analogue α-cyanostilbene and benzophenone hydrazone by the imine linkage. Its chemical structure was verified by FT-IR, MALDI-TOF-MS, HR-MS and 1H/13C NMR technologies. It could exhibit a red fluorescence based on the synergistical effects of aggregation-induce emission (AIE), excited-state intramolecular proton transfer (ESIPT) and twisted intramolecular charge-transfer (TICT) in the aggregation or solid states. Interestingly, the TLC-based test strip loaded with the target compound showed the reversible fluorescence response to amine/acid vapor and on-site visual fluorescence quenching response to Fe3+. In THF/water mixtures (fw = 90%, 10 µM, pH = 7.4), the detection limit (DL) and the binding constant (Ka) of the developed probe towards Fe3+ were evaluated as 5.50 × 10− 8 M and 1.69 × 105, respectively. The developed probe was successfully applied for the detection of Fe3+ with practical, reliable, and satisfying results. [ABSTRACT FROM AUTHOR]

A pair of 1,8-naphthalimides (NPIs) were designed and successfully synthesized through embellishing amino-containing NPI with 4-diethylaminosalicyladehyde and 4-diethylaminobenzaldehyde, respectively. Their structures were fully confirmed by 1 H/ 13 C NMR, HR-MS and FT-IR spectroscopic studies. Their photophysical properties were systematically investigated in different solvents of varied polarity, in THF/water mixtures with varying water fractions (f w ), and in THF solvent with varying concentrations of NPIs. It inferred that the distinct differences in emission between two NPIs during self-assembled process could be ascribed that the hydroxyl-containing NPI allowed the excited-state intramolecular proton transfer process between -OH and CH=N units in the aggregation state. Interestingly, the solid of 4-diethylaminosalicyladehyde-functionalized NPI exhibited multi-stimuli-responsive fluorescence changes involving mechanofluorochromism and HCl/NH 3 vapor stimulus-induced conversion. However, no remarkable change was observed in the photoluminescence (PL) spectra for the solid of 4-diethylaminobenzaldehyde-functionalized NPI under the stimuli of mechanical force and organic solvent., (© 2024 John Wiley & Sons Ltd.)

A simple α -cyanostilbene-functioned salicylaldehyde-based Schiff-base probe, which exhibited outstanding 'aggregation-induced emission and excited state intramolecular proton transfer (AIE + ESIPT)' emission in solution, aggregation and solid states, was synthesized in high yield of 87%. Its solid-states with different morphologies emitted different fluorescence after crystallization in EtOH/H 2 O (1/2, v/v) mixtures or pure EtOH solvent. Besides, it exhibited an obvious spectro-photometrical fluorescence quenching for highly selective sensing of Co 2+ in THF/water system (ƒ w = 60%, pH = 7.4), accompanied by an intense green fluorescence turn-off behavior under UV 365nm illumination. The binding stochiometry between the ligand and Co 2+ was found to be 2:1, and the detection limit (DL) was calculated to be 0.41 × 10 -8 M. In addition, it could be applied to detect Co 2+ in real water samples and on silica gel testing strip., (© 2022 IOP Publishing Ltd.)

Aim of the Study: To investigate the effects of P27RF-Rho on hepatocellular carcinoma (HCC) cell growth and explore the possibility of using it as a novel therapeutic target for liver cancer treatment., Material and Methods: P27RF-Rho in HCC cells was silenced by lentivirus-mediated RNA interference, and the silencing effect was verified by RT-PCR. Cell proliferation was determined by MTT and clone formation assay. Cell cycle phase and apoptosis were detected through FACS. The expression level of cell growth, apoptosis, and metastasis associated genes was detected by quantitative PCR., Results: Lentivirus-mediated P27RF-Rho knockdown inhibited HCC cell growth and clone formation. P27RF-Rho silence induced cell cycle arrest and apoptosis. The mRNA level of genes associated with cell cycle, apoptosis, and invasion also significantly altered after P27RF-Rho knockdown. Cyclin A, CDK2, BCL-2, and MMP-9 were down-regulated. P27 and Bax were up-regulated., Conclusions: P27RF-Rho knockdown inhibits HCC cell growth, and P27RF-Rho is probably a promising target for HCC treatment., Competing Interests: The authors declare no conflict of interest.