Colorimetric determination of cholesterol based on the peroxidase-like activity of Cu-Salt-Fe nanozyme with multiple active sites.

A strategy to enhance the peroxidase-like activity of the hemin composite is presented. The Cu-Salt-Fe with enhanced activity was synthesized by one-step heat treatment and applied to the colorimetric determination of free cholesterol in human serum. Phosphate can act in complexing Cu to form a carrier Cu-Floc with a large specific surface area.

Smartphone-assisted ratiometric fluorescence sensing platform and logical device based on polydopamine nanoparticles and carbonized polymer dots for visual and point-of-care testing of glutathione.

As a crucial biothiol, glutathione (GSH) plays a key role in the organisms. Monitoring GSH level is of great significance for disease diagnosis and biomedical research. In this work, polydopamine (PDA) nanoparticles-red fluorescent carbonized polymer dots (r-CPDs) based ratiometric fluorescence sensing platform was constructed and employed for GSH assay.

Nitrogen-Doped Carbon Dot and CdTe Quantum Dot Dual-Color Multifunctional Fluorescent Sensing Platform: Sensing Behavior and Glucose and pH Detection.

A novel fluorescent probe based on a nitrogen-doped carbon dot (N-CD) and CdTe quantum dot (CdTe QD) platform has been constructed for HO/glucose detection and pH sensing. In this work, HO-tolerant blue fluorescence N-CDs were added to the HO-mediated yellow fluorescence quenching of CdTe QDs to construct a dual-color ratiometric fluorescent HO probe. HO-induced passivated group detachment and action on deep nanocrystals promoted CdTe QD fluorescence quenching.

Microwave-assisted extraction (MAE) combined with gas chromatography-mass spectrometry (GC-MS) for determination of volatile small molecules to evaluate compatibility of antimicrobial peptide PL-5 spray with packaging materials.

A simple and efficient method involving microwave-assisted extraction (MAE) combined with GC-MS was established to determine 1,3-di-tert-butylbenzene (DBB), 2,4-di-tert-butylphenol (DBP), 3,5-di-tert-butyl-4-hydroxybenzaldehyde (DBHBA) for evaluating the compatibility of antimicrobial peptide PL-5 spray with drug-packaging materials. In this study, the antimicrobial peptide PL-5 spray was purified using a Welchrom C18 column, and the high-density polyethylene spray bottle with liquid collection tube was first mixed with absolute ethanol, which would be subjected to MAE for further measurement by GC-MS. Various experimental parameters were systematically optimized, and good linearities were obtained within the range of 0.