Development of a novel label-free NIR aptasensor based on triphenylmethane dyes for rapid and sensitive detection of copper ions.

Heavy metal pollution, particularly from copper ions (Cu), poses a significant threat to both the ecological environment and human health. However, traditional copper ion analysis techniques are often hindered by the need for expensive equipment, labor-intensive sample preparation and skilled operation, which limits their effectiveness for field and real-time applications. In this work, we report a novel near-infrared aptamer sensor (NIRApt) that originates from the binding reaction between the DNA aptamer Apt and the fluorescent small molecule crystal violet (CV), enabling rapid detection of Cu through the competitive effect of Cu with Apt.

Single-molecule analysis of genome-wide DNA methylation by fiber FISH coupled with atomic force microscopy.

DNA methylation (mainly at 5-methylcytosine, 5mC) plays an essential role in embryonic development and cellular biology. Alterations in DNA methylation are associated with disease development, especially hematologic malignancies. To investigate the potential of 5mC for diagnosis and treatment, accurate determination of 5mC is essential.

Subtle Structural Changes of Dyes Lead to Distinctly Different Fluorescent Behaviors in Cellular Context: The Role of G-Quadruplex DNA Interaction Using Coumarin-Quinazolinone Conjugates as a Case Study.

Fluorogenic organic materials have gained tremendous attention due to their unique properties. However, only a few of them are suitable for bioimaging. Their different behaviors in organic and cellular environments hinder their application in bioimaging.

Fluorogenic probes for mitochondria and lysosomes via intramolecular photoclick reaction.

The tetrazole-based photoclick chemistry has attracted considerable attention in virtue of its good biocompatibility, exclusive molecular reaction, and spatiotemporally controllable properties. Using this photoclick reaction, we designed an in situ, real-time fluorescence imaging system that targeted mitochondria and lysosomes in a spatiotemporally controllable manner. Upon irradiation, the pyrazoline fluorophore was generated in situ by the intramolecular tetrazole-alkene cycloaddition reaction ("photo-click chemistry").

Gestated uniform yolk-shell Sn@N-doped hollow mesoporous carbon spheres with buffer space for boosting lithium storage performance.

Based on the confined growth strategy and hydrogen thermal reduction, uniform yolk-shell structured Sn@NHMCSs were designed with metal Sn as the core and mesoporous carbon as the shell. The void between the Sn yolk and carbon shell provides enough buffer space for the expansion of the alloying reaction of Sn, which greatly improves the poor cycling stability of Sn as an anode material in lithium ion batteries. In addition, we observed that tiny particles were still encapsulated in the hollow carbon sphere cavity after the alloying/dealloying reaction.

One-step synthesis of N-doped carbon dots, and their applications in curcumin sensing, fluorescent inks, and super-resolution nanoscopy.

Nitrogen-doped carbon dots (N-CDs) with fluorescence excitation/emission maxima at 365/450 nm were prepared by a one-step hydrothermal approach. The dots possess remarkable photostability, fluorescence blinking and good biocompatibility, and this favors utilization in stochastic optical reconstruction microscopy (STORM). A spatial resolution down to ~60 nm was achieved when imaging HeLa cells using 647-nm laser excitation.

One-step microwave-assisted preparation of oxygen-rich multifunctional carbon quantum dots and their application for Cu-curcumin detection.

Carbon quantum dots (CQDs), owing to its unique optical properties, have achieved tremendous progress for the detection of different metal ions, organic small molecules, macromolecules, etc. Here we synthesized fluorescent CQDs by a simple one-step microwave-assisted method using 3,4-Dihydroxy-l-phenylalanine (levodopa) as the carbon resource. The CQDs proved to be a multifunctional probe which can be used for detection of various species including copper ion, biothiols and curcumin, via different mechanisms.

High-performance liquid chromatography study of gatifloxacin and sparfloxacin using erythrosine as post-column resonance Rayleigh scattering reagent and mechanism study.

Herein, a highly selective high-performance liquid chromatography (HPLC) coupled with resonance Rayleigh scattering (RRS) method was developed to detect gatifloxacin (GFLX) and sparfloxacin (SPLX). GFLX and SPLX were first separated by HPLC, then, in pH 4.4 Britton-Robinson (BR) buffer medium, protonic quaternary ammonia cation of GFLX and SPLX reacted with erythrosine (ERY) to form 1:1 ion-association complexes, which resulted in a significant enhancement of RRS signal.

The fluorescence and resonance Rayleigh scattering spectra study on the interactions of palladium (II)-Nootropic chelate with Congo red and their analytical applications.

A highly sensitive detection approach of resonance Rayleigh scattering spectra (RRS) is firstly applied to analyzing nootropic drugs including piracetam (PIR) and oxiracetam (OXI). In HCl-NaAc buffer solution (pH=3.0), the OXI chelated with palladium (II) to form the chelate cation [Pd·OXI], and then reacted with Congo red (CGR) by virtue of electrostatic attraction and hydrophobic force to form binary complex [Pd·OXI].