Fluorescent Imaging Probe from Nanoparticle Made of AIE Molecule

Abstract

Aggregation induced emission (AIE) active molecules are widely used for fluorescence “turn-on” detection applications with the unique advantages over conventional fluorescent probes. Transformation of AIE molecule into functional nanoparticle can greatly expand their biomedical application potential. Here we report an approach for preparation of 20–80 nm size functional nanoparticle made of AIE molecule. The approach involves aggregation of AIE active tetraphenylethene (TPE) molecule in the presence of functional TPE molecule. Following this approach we have synthesized TPE-based nanoparticle functionalized with polyethylene glycol, primary amine, aspartic acid, glucose, and arginine. Compared to reported methods of making AIE-based nanoparticles, presented nanoparticles have distinct advantages that they are composed of AIE molecules only (without any non-AIE molecule/polymer) and wide variety of surface functionalization can be achieved by this approach. Nanoparticles have good colloidal stability with fluorescence quantum yield of 12–15% and fluorescence remains intact in the presence of conventional quenchers. These nanoprobes are used as fluorescent cell labels and can be extended for preparation of AIE molecule-based different nanoprobes.

Solvent‐Dependent Nanostructures Based on Active π‐Aggregation Induced Emission Enhancement of New Carbazole Derivatives of Triphenylacrylonitrile

“…The development of novel fluorescent nanoparticle based bioimaging probes has created new avenues in interdisciplinary fields that range from biology to materials science . Their remarkable optical properties make them promising for drug delivery, bioanalysis, bioimaging and other biomedical applications . Previously, a large number of inorganic fluorescent nanoparticles including quantum dots, silicon quantum dots, carbon dots, fluorescent metal clusters and Ln 3+ ‐ion doped nanomaterials have been extensively explored for bio/chemosensor applications .…”

“…The simplest approach is the incorporation of an AIE moiety into the self‐assembled/aggregated structure of polymers or molecules and this has emerged as a fascinating aspect because of their optimum flexibility, extensive π–π interaction, and the feasibility of peripheral modification with various functional groups for enhanced intermolecular interactions . The size of these nanoparticles have been restricted to between 25 and 300 nm for successful biomedical applications …”

“…Thirdly, most of these nanoparticles have low colloidal stability and frequently lose their assembled structure. Fourthly, very few functionalization methods have been presented with respect to various functional nanoparticles made of inorganic nanoparticles . A comparison table with the reported nanoparticles made by AIE luminogen is given in the Supporting Information (Table S1) to show the novelty of the probes.…”

“…[1] Their remarkable optical properties maket hem promisingf or drug delivery,b ioanalysis, bioimaging and other biomedical applications. [2][3][4] Previously,al arge number of inorganicf luorescent nanoparticles including quantum dots, silicon quantum dots, carbon dots,f luorescentm etal clusters and Ln 3 + -ion doped nanomaterials have been extensivelye xplored for bio/chemo-sensora pplications. [5][6][7][8][9][10][11] In spite of the advantages of strong fluorescencei ntensity and limited dosage, fluorescenti norganic nanoparticles have many inherent disadvantagesf or biomedicala pplications, such as relatively laborious synthesis, difficult to tune fluorescence, potentialt oxicity due to their accumulationi nt he reticuloendothelial system (RES) after intravenous injection, blinking effect,p oor biodegradability and nonfunctionalized hydrophobic entities.…”

“…[37][38][39] The size of these nanoparticles have been restricted to between 25 and3 00 nm for successful biomedical applications. [2] Althoughs ignificant progress has been made in the development of AIE activen anoprobes, there are still several issues that prevent their wider application.F irstly,t he presence of non-AIE molecule/polymeri nt he core of AIE-based nanoparticle makes itsf luorescencep roperties highly dependent on the amount of AIE molecule. Secondly,s ynthesis of fluorescent nanoparticles of controlled size is very difficult by these methods because of the existence of non-AIE materials.…”