Enzyme‐Instructed Self‐Assembly Enabled Monomer–Excimer Transition to Construct Higher Ordered Luminescent Supramolecular Assembly for Activity‐based Bioimaging

Abstract

It is challenging to construct high-performing excimer-based luminescent analytic tools at low molecular concentrations.Wereport that enzyme-instructed self-assembly (EISA) enables the monomer-excimer transition of acoumarin dye (Cou)a tl ow molecular concentrations,a nd the resulting higher ordered luminescent supramolecular assemblies (i.e., nanofibers) efficiently record the spatiotemporal details of alkaline phosphatase (ALP) activity in vitro and in vivo. Cou was conjugated to short self-assembly peptides with ah ydrophilic ALP-responsive group.B yA LP triggering,E ISA actuated an anoparticles-nanofibers transition at low peptide concentrations followed by monomer-excimer transition of Cou.Analysis of structure-property relationships revealed that the self-assembly motif was ap rerequisite for peptides to induce the monomer-excimer transition of Cou.L uminescent supramolecular nanofibers of pYD (LSN-pYD)i lluminated the intercellular bridge of cancer cells and distinguished cancer cells (tissues) from normal cells (tissues) efficiently and rapidly,p romising potential use for the early diagnosis of cancer.This work extends the functions of EISA and provides anew application of supramolecular chemistry.

Alkaline Phosphatase: A Reliable Endogenous Partner for Drug Delivery and Diagnostics

“…Various NIR fluorescence and MRI bimodal imaging probes have been reported for molecular imaging. [284,285] How- A peptide derivative, NBD-GFFpY-ss-ERGD Phosphate moiety For liver cancer diagnostics [275] A mitochondria-targeted near-infrared (NIR) activatable fluorescent/ photoacoustic probe Phosphate ester moiety For biomodal imaging of prostate cancer [297] A hydrogelator, Nap-FFFYp-EDA-DOTA(Gd) Phosphate moiety of the probe Enhanced magnetic imaging of the tumors, imaging in vivo enzyme activity [298] Enzyme induced self-assembly based monomer-excimer transition of low molecular concentration coumarin dye L-Phosphotyrosine residue Supramolecular assemblies with enhanced imaging performance [299] Aggregation Hybridized electrochemical biosensor Intracellular pyrophosphate Wireless biosensors diagnose the cancer by investigating the interaction between cells and modified surfaces [300] Nitrogen doped carbon dots Pyrophosphate Detection of ALP activity for clinical diagnostics [301] TPE-Py-FpYGpYGpY Tyrosine phosphate residue Selective tumor imaging [288] Chemiluminiscence Enzyme-activated chemiluminiscence nanoprobe…”

Peptide-Based Low Molecular Weight Photosensitive Supramolecular Gelators

“…Spiropyran [ 24 , 78 , 80 ] is another critical photo-sensitive unit for light-induced ring-opening and closing behavior. The 2-nitrobenzyl (NB) group [ 95 , 96 , 97 , 98 ], coumarin [ 99 , 100 , 101 ], anthracene [ 102 , 103 , 104 ], and diarylethene [ 105 , 106 ] units are also used to create light-responsive gels ( Figure 1 ). The molecular structure and light-induced structural changes of the most well-studied and explored photo-switches in recent years are shown in Figure 1 .…”

Supramolecular Nanomedicines of In-Situ Self-Assembling Peptides

“…In addition, they proposed a strategy for enzymatically self-assembling nanofibers to make fluorophores form excimer complexes at low concentrations and in biological environments. (Zhong et al, 2021). And they also used the strategy of combining small molecule peptides with EISA properties and AIE groups with high fluorescence brightness and reactive oxygen generation in the aggregated state, the identification and elimination of senescent cancer cells had been successfully achieved.…”