A Novel Water‐Soluble Fluorescence Probe with Wash‐Free Cellular Imaging Capacity Based on AIE Characteristics

Abstract

A potential real-time imaging water-soluble fluorescent polymer (P3) is facilely prepared via one-pot method. For P3, tetraphenylethene unit serves as the fluorescent unit, poly(acryloyl ethylene diamine) (a kind of polyelectrolyte) with specific degree of polymerization acts as water-soluble part. H-NMR, gel permeation chromatography (GPC), UV-vis spectroscopy, photoluminescence (PL), and confocal laser scanning microscopy are undertaken to characterize the structure and property of P3. The results of wash-free cellular imaging show that the signal-to-noise ratio is high as the concentration of P3 is 50 μg mL . In addition, the pH-responsive and Cd -responsive are also investigated in this paper. The results coming from pH-responsive show that P3 solution displays significant fluorescence under near neutral. And the result from the cellular imaging shows that intracellular fluorescence intensity enhances with the augment of concentration of Cd , which reveals that P3 can give a hint to resolve the dilemma of traditional fluorescent dyes used as living cellular fluorescent probe.

Controlled aggregation of amphiphilic aggregation‐induced emission polycation and superparamagnetic iron oxide nanoparticles as fluorescence/magnetic resonance imaging probes

“…However, for the PEG‐PEI‐TPE/SPIO probe, the core is PAA‐coated SPIO; hence, the aggregation of TPE in PEG‐PEI‐TPE/SPIO should occur around the SPIO core in water, which is responsible for the stacking and RIR process of TPE [Scheme (c)]. A number of factors such as the concentration, hydrophobicity, rigidity, and chain length of TPE incorporated polymers, and the temperature and viscosity of the TPE solution will affect the RIR process of TPE, namely, influence the fluorescence properties of TPE . As a result, there may be three possible reasons that can explain why the fluorescence intensity and lifetime of PEG‐PEI‐TPE/SPIO is longer than PEG‐PEI‐TPE, especially at lower concentrations: first, SPIO can be considered as a core crosslinking agent of PEG‐PEI‐TPE, which may improve the stability of aggregates of TPE; second, the crosslinking of PEG‐PEI‐TPE may help to bring TPE closer, which will further promote the RIR process; thirdly, the polymer chain of PAA becomes more hydrophobic after coupled by PEG‐PEI‐TPE.…”

An Easily Accessible Ionic Aggregation‐Induced Emission Luminogen with Hydrogen‐Bonding‐Switchable Emission and Wash‐Free Imaging Ability

“…Ther esults demonstrated that DBTAc ould easily enter biological samples including living cells and fish larva, and showed excellent signal to noise ratio without washing the unstained dye.D BTAi sm uch easier to access than the existing AIE wash-free imaging systems. [26,27] In summary,w eh ave developed an ovel water-soluble ionic AIEgen DBTAb yasimple one step reaction with adecent yield. Thefacile access of DBTAisvery attractive in terms of saving time,labor,and economy cost.…”

“…Without washing,t he fluorescence image was collected by staining with DBTAfor 30 min, which showed strong fluorescence in HeLa cells and negligible background fluorescence.I nsharp contrast, the fluorescence image obtained by incubation with Cy3 dye exhibited strong fluorescence in the whole imaging area. [26,27] In summary,w eh ave developed an ovel water-soluble ionic AIEgen DBTAb yasimple one step reaction with adecent yield. Thef luorescence image collected without washing showed bright blue-greenish fluorescence inside the fish larva and almost no background signal.…”

An Easily Accessible Ionic Aggregation‐Induced Emission Luminogen with Hydrogen‐Bonding‐Switchable Emission and Wash‐Free Imaging Ability

“…The results demonstrated that DBTA could easily enter biological samples including living cells and fish larva, and showed excellent signal to noise ratio without washing the unstained dye. DBTA is much easier to access than the existing AIE wash‐free imaging systems …”