Multiregulation of Aggregation‐Induced Emission (AIE) via a Competitive Host–Guest Recognition and α‐Amylase Hydrolyzing

Abstract

The multiregulation of aggregation‐induced emission (AIE) that responds to external stimuli to finish multifunctions has become a focus of interest in biodiagnosis. Host–guest‐ recognition is an efficient strategy to introduce switchable, reversible, and other functional properties into AIE molecules. Herein, an amphiphilic tetraphenylethylene (TPE) derivative TPE‐PEG is prepared via the simple amidation reaction and chosen as an AIE‐based guest polymer. The aggregated state of TPE‐PEG is altered and the fluorescence of TPE‐PEG can be turned off in the presence of γ‐cyclodextrins (γ‐CDs) due to the formation of host–guest complex between TPE units and γ‐CDs. TPE units in the cavities of γ‐CDs are released free and an aggregated state of TPE‐PEG is restored via the guest competition epistasis of bile acid. Meanwhile, α‐amylase can hydrolyze the host molecules of γ‐CDs, resulting in an aggregated state of TPE‐PEG again and turning the fluorescence on subtly. This reversible multiregulation of fluorescence may meet the multirequirements for the diagnosis in vivo due to the biological nature of α‐amylase and bile acid.

Emission‐Tunable Nanofluorophores through Self‐assembly of Amphiphilic Block Copolymers: toward Application in Cell Imaging

“…[ 44 ] Polyethylene glycol (PEG) should be an ideal candidate for the hydrophilic segment since it is commercially available and has good biocompatibility, low immunogenicity, and good water solubility. [ 45‐50 ]…”