Ultrafast and Noninvasive Long-Term Bioimaging with Highly Stable Red Aggregation-Induced Emission Nanoparticles

Abstract

Strongly red luminescent and water-soluble probes are very important for studying biological events and processes. Fluorescent nanoparticles (NPs) built from the aggregation-induced emission luminogen (AIEgen) and amphipathic polymeric matrixes have been considered as promising candidates for bioimaging. However, AIE NPs with long-wavelength absorption suitable for in vivo application are still scarce. In this work, three AIE-active red-emissive BODIPY derivatives with long-wavelength absorption were rationally designed and synthesized. Then three NPs based on these AIEgens exhibit bright red photoluminescence with high fluorescence quantum yield in aqueous media. These NPs uniformly dispersed in water and showed excellent stability and good biocompatibility. They can be readily internalized by HeLa cells, and the staining process is performed by simply shaking the culture with cells for just a few seconds at room temperature, which indicates an ultrafast and easy-to-operate staining protocol. More importantly, long-term tracing in living cells and mouse over 15 days is successfully achieved. The strong fluorescence signals, ultrafast staining procedure, and long-term tracing abilities indicate that these AIE NPs hold great potential for monitoring biological processes.

Recent Progress of BODIPY Dyes With Aggregation-Induced Emission

“…Moreover, these NPs showed an ultrafast cell staining time of a few seconds and excellent cell imaging ability. More importantly, these NPs can be used for long term imaging both in vitro and in vivo (Figure 9), demonstrating their great potential imaging abilities in the practical biological applications (Che et al, 2019).…”

“… (A) Preparation of the AIE NPs of compound 12 . (B) In vivo confocal images of the tumor-bearing mouse with AIE NPs of compound 12 from day 0 to day 14 (adapted with permission from Che et al, 2019, Copyright 2019, Royal Chemistry Society).…”

“…Taking the advantages of AIE, the intense aggregation-state fluorescence of BODIPYs has been successfully achieved. Moreover, their application as aggregation-state emitters for bioimaging, stimuli-response switches as well as OLEDs has been demonstrated (Mei et al, 2015; Baysec et al, 2018; Che et al, 2019). This mini review focuses on providing an overview of the design, mechanism and application of AIE-active BODIPYs and BODIPY analogs so as to facilitate their future application in the solid-state luminescence field.…”

Bright red aggregation-induced emission nanoparticles for multifunctional applications in cancer therapy

“…[15][16][17][18][19][20][21] Long incubation times and harsh incubation conditions are critical barriers for cellular uorescence imaging in clinical applications. [22][23][24][25] Cancer treatments mainly include three essential steps: ultrafast staining, therapy, and long-term tracing. The former two play important roles for the discovery and excision of tumors, and the last is to further monitor the metastasis of residual tumor.…”

Color-tunable single-fluorophore supramolecular system with assembly-encoded emission

“…Tang et al have developed a series of fluorophores whose aggregates emit more strongly than monomers, called aggregation-induced emission (AIE) [31][32][33] . The AIE fluorophores have proven to be effective as turn-on fluorescent sensors, thus exhibiting great potential in the biological imaging field 34 . Alternatively, supramolecular chemists have discovered fluorophores whose emission properties can be affected by noncovalent interactions 14,16,35,36 .…”