Simultaneously Monitoring Multiple Autophagic Processes and Assessing Autophagic Flux in Single Cells by Fluorescence Cross-Correlation Spectroscopy.

Autophagy is a widely conserved and multistep cellular catabolic process and maintains cellular homeostasis and normal cellular functions the degradation of some harmful intracellular components. It was reported that high basal autophagic activity may be closely related to tumorigenesis. So far, the fluorescence imaging technique has been widely used to study autophagic processes, but this method is only suitable for distinguishing autophagosomes and autolysosomes.

measurement of autophagic flux by fluorescence correlation spectroscopy.

Autophagy is a fundamental and phylogenetically conserved self-degradation process and plays a very important role in the selective degradation of deleterious proteins, organelles, and other macromolecules. Although flow cytometry and fluorescence imaging techniques have been used to assess autophagic flux, we remain less able to monitor autophagic flux in a highly sensitive, robust, and well-quantified manner. Here, we reported a new method for real-time and quantitatively monitoring autophagosomes and assessing autophagic flux in living cells based on fluorescence correlation spectroscopy (FCS).

quantitative measurements on MMP-9 activity in single living cells by single molecule fluorescence correlation spectroscopy.

Matrix metalloproteinase-9 (MMP-9) plays an important role in tumor progression. It is of great significance to establish a sensitive assay strategy for MMP-9 activity in single living cells. Here a novel single molecule spectroscopy method based on the fluorescence correlation spectroscopy (FCS) technique was proposed for measuring the MMP-9 activity at different locations within single living cells, using a fluorescent specific peptide and a reference dye as dual probes.

A study of protein-drug interaction based on solvent-induced protein aggregation by fluorescence correlation spectroscopy.

The identification of molecular targets for achieving beneficial effects from small-molecule drugs is a crucial and currently unsolved challenge, which leads to high costs and long development cycles. Therefore, it is urgent to develop methods for easily and quickly acquiring information about protein-drug interaction at a molecular level. In this study, we propose a novel method for the study of protein-drug interaction by fluorescence correlation spectroscopy (FCS) based on organic solvent-induced protein aggregation.

Single-Particle Catalytic Analysis by a Photon Burst Counting Technique Combined with a Microfluidic Chip.

Single-particle catalytic analysis plays an important role to understand the catalytic mechanism of nanocatalysts. Currently, some methods are used to study the relationship between single-particle catalytic activity and morphology. However, there is still lack of a simple and rapid analysis method for evaluating the catalytic activity of an individual nanocatalyst that freely moves in solution.

A dual-responsive fluorescent probe for detection of fluoride ion and hydrazine based on test strips.

Hydrazine (NH) and fluoride ion (F) are regarded as environmental pollutants and potential carcinogens. A dual-functional fluorescent probe (probe 1) was developed for both F and NH with high selectivity and sensitivity. 1 was based on nucleophilic aromatic substitution reaction for NH detection and selective cleavage of 4-nitrobenzenesulphonyl group for the determination of F.

A highly selective fluorescent probe for the detection of hypochlorous acid in tap water and living cells.

A turn-on fluorescent probe (DAME) for sensing hypochlorous acid (HClO) with excellent selectivity was presented. The fluorescent probe was composed of coumarin derivative as the fluorophore and dimethylcarbamothioic chloride group with a sulfide moiety as modulator. Additionally, the sulfide moiety would be oxidized by HClO, and then free dye of coumarin derivate was released and exhibited significant fluorescence.

Carbon Dots with Red Emission for Sensing of Pt, Au, and Pd and Their Bioapplications in Vitro and in Vivo.

Red emissive carbon dots (CDs) have drawn more and more attention due to their good organ penetration depth and slight biological tissue photodamage. Herein, the fluorescent CDs with red emission were synthesized by the facile one-pot hydrothermal treatment of citric acid and neutral red and they show red fluorescence both in aqueous solution and solid state. The solution of CDs exhibits the quantum yield of 12.