Solid-Phase Pyrolysis Synthesis of Amino Acid-Based Nitrogen-Doped Carbon Dots as an "On-Off-On" Fluorescent Probe for the Detection of Copper Ions and Glutathione.

This study introduces the synthesis of amino acid-based nitrogen-doped carbon dots (N-L-Ser-CDs) from L-serine (L-Ser) and urea through a straightforward and economical one-step solid-phase pyrolysis process. The incorporation of nitrogen into the carbon dots resulted in a remarkable 27.6-fold increase in fluorescence intensity, featuring a peak emission at 405 nm when excited at 330 nm and a significant fluorescence quantum yield of 22.

Biocompatible sulfur nitrogen co-doped carbon quantum dots for highly sensitive and selective detection of dopamine.

In this work, sulfur and nitrogen co-doped carbon quantum dots (S,N-CQDs) were prepared via one-pot hydrothermal treatment of EDTA disodium and sodium sulfide. The prepared S,N-CQDs were characterized by TEM, XRD, FT-IR, XPS, UV-vis absorption and fluorescence spectra to characterize their morphology, crystal structure, functional groups, elemental composition, and optical properties. It was found that S and N elements were successfully doped into the CQDs and the morphology was approximately spherical with an average particle size of 2.

Multi-Evaluating Strategy for Siji-kangbingdu Mixture: Chemical Profiling, Fingerprint Characterization, and Quantitative Analysis.

Siji-kangbingdu mixture is an anti-inflammatory, anti-bacterial, and anti-viral herbal mixture which is frequently used by doctors to treat upper respiratory infections. It's important to establish an efficient and economical quality-control method to ensure the quality consistency and efficacy stability of Siji-kangbingdu mixture. In this study, an integrated multi-evaluation method was established, sequentially involving UPLC-TripleTOF-MS analysis, UPLC fingerprint analysis, and the quantitative analysis of multi-components using the single-marker (QAMS) method.