Enabling controllable time-dependent phosphorescence in carbonized polymer dots based on chromophore excited triplet energy level modulation by ionic bonding.

Time-dependent phosphorescence color (TDPC) materials are highly attractive for realizing multitiered dynamic information encryption and anti-counterfeiting. It's extremely challenging to modulate puzzle of multiple luminescence species and understand the intrinsic mechanism. Herein, we demonstrate a novel and synthesize-friendly strategy to develop a high contrast TDPC carbonized polymer dots (CPDs) with adjustable lifetime and quantum yields.

Cellular Uptake of Cell-Penetrating Peptides Activated by Amphiphilic p-Sulfonatocalix[4]arenes.

We report the synthesis of a series of amphiphilic p-sulfonatocalix[4]arenes with varying alkyl chain lengths (CX4-Cn) and their application as efficient counterion activators for membrane transport of cell-penetrating peptides (CPPs). The enhanced membrane activity is confirmed with the carboxyfluorescein (CF) assay in vesicles and by the direct cytosolic delivery of CPPs into CHO-K1, HCT 116, and KTC-1 cells enabling excellent cellular uptake of the CPPs into two cancer cell lines. Intracellular delivery was confirmed by fluorescence microscopy after CPP entry into live cells mediated by CX4-Cn, which was also quantified after cell lysis by fluorescence spectroscopy.

Label-Free Fluorescent Kinase and Phosphatase Enzyme Assays with Supramolecular Host-Dye Pairs.

The combination of the macrocyclic hosts sulfonatocalix[4]arene and cucurbit[7]uril with the fluorescent dyes lucigenin and berberine affords two label-free enzyme assays for the detection of kinase and phosphatase activity by fluorescence monitoring. In contrast to established assays, no substrate labeling is required. Since phosphorylation is one of the most important regulatory mechanisms in biological signal transduction, the assays should be useful for identification of inhibitors and activators in high-throughput screening (HTS) format for drug discovery.

A supramolecular five-component relay switch that exposes the mechanistic competition of dissociative versus associative binding to cucurbiturils by ratiometric fluorescence monitoring.

A putrescine derivative of aminomethyladamantane is established as a ditopic guest with two mutually exclusive binding sites for cucurbit[6]uril and cucurbit[7]uril. A mixture containing both hosts, the ditopic guest, and two fluorescent dyes affords a relay system with a ratiometric fluorescence response and enables a kinetic analysis of the switching mechanism.

A self-assembled white-light-emitting system in aqueous medium based on a macrocyclic amphiphile.

A novel FRET platform was fabricated based on a macrocyclic amphiphile, reliant on the self-sorting complexation of a donor on the periphery of the assemblies and entrapment of an acceptor within the inner hydrophobic phase. By tuning subtly the donor/acceptor ratio, white light emission was successfully achieved with high quantum yield.

Photomodulated fluorescence of supramolecular assemblies of sulfonatocalixarenes and tetraphenylethene.

Self-assembled fluorescent nanoparticles responding to specific stimuli are highly appealing for applications such as labels, probes, memory devices, and logic gates. However, organic analogues are challenging to prepare, due to unfavorable aggregation-caused quenching. We herein report the preparation of self-assembled fluorescent organic nanoparticles in water by means of calixarene-induced aggregation of a tetraphenylethene derivative (QA-TPE) mediated by p-sulfonatocalix[4]arenes.