No abstract

Precise molecular engineering is the most fundamental and even a great challenging task for the development of small organic fluorophores used as phototheranostic agents in multimodal imaging-guided synergistic therapy. To the best of our knowledge, there have been no previous reports regarding the fine fabrication of molecular structure from a proof-of-concept study, providing a single molecule with all phototheranostic modalities. Herein, an electron donating–accepting (D–A) system is constructed by using triphenylamine derivatives as donors and diverse electron-deficient partners as acceptors, yielding aggregation-induced emission luminogens with tunable emission wavelength (up to 933 nm) and light absorption capability (ε up to 6.9 × 104 M–1 cm–1). Notably, by integrating the spin–orbit coupling-promoted carbonyl group and the strong stretching vibrations of −CN to the D–A systems, a highly performing phototheranostic agent, namely, MeTIC, is constructed. When encapsulating MeTIC into nanovehicles, the obtained MeTIC nanoparticles show excellent performance in multimodality theranostics for cancer treatment. This work is expected to provide an organic phototheranostic agent designing principle for potential clinical trials.

There is a great demand to understand cell transplantation, migration, division, fusion, and lysis. Correspondingly, illuminant object-labeled bioprobes have been employed as long-term cellular tracers, which could provide valuable insights into detecting these biological processes. In this work, we designed and synthesized a fluorescent polymer, which was comprised of hydrophilic N-isopropylacrylamide polymers as matrix and a hydrophobic tetraphenylethene (TPE) unit as AIE-active cross-linkers (DDBV). It was found that when the feed molar ratio of N-isopropylacrylamides to cross-linkers was 22:1, the produced polymers demonstrated the desirable LCST at 37.5 °C. And also, the temperature sensitivity of polymers could induce phase transfer within a narrow window (32-38 °C). Meanwhile, phase transfer was able to lead the florescent response. And thus, we concluded that two responses occur when one stimulus is input. Therefore, the new cross-linker of DDBV rendered a new performance from PNIPAm and a new chance to create new materials. Moreover, the resulted polymers demonstrated very good biocompatibility with living A549 human lung adenocarcinoma cells and L929 mouse fibroblast cells, respectively. Both of these cells retained very active viabilities in the concentration range of 7.8-125 μL/mg of polymers. Notably, P[(NIPAm)22-(DDBV)1] (P6) could be readily internalized by living cells with a noninvasive manner. The cellular staining by the fluorescent polymer is so indelible that it enables cell tracing for at least 10 passages.

No abstract

Herein, we report a set of novel AIE-active fluorescent probes containing pyridiniums and boric acid groups with the applications of ATP recognition and specific tracking of different cell organelles.