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Chemodynamic therapy (CDT) employs Fenton catalysts to kill cancer cells by converting intracellular H

Chemodynamic therapy (CDT) utilizes iron-initiated Fenton chemistry to destroy tumor cells by converting endogenous H

Three new mononuclear copper(II) complexes, [Cu(L2)](2+) (1), [Cu(acac)(L)](+) (2), and [Cu(acac-Cl)(L)](+) (3) (L = 2-(4-pyridine)oxazo[4,5-f]1,10-phenanthroline (4-PDOP); acac = acetylacetone; acac-Cl = 3-chloroacetylacetone), have been synthesized and characterized by elemental analysis, high resolution mass spectrometry (Q-TOF), and IR spectroscopy. Two of the complexes were structurally characterized by single-crystal X-ray diffraction techniques. Their interactions with DNA were studied by UV-vis absorption and emission spectra, viscosity, thermal melting, DNA unwinding assay and CD spectroscopy. The nucleolytic cleavage activity of the compounds was carried out on double stranded pBR322 circular plasmid DNA by using a gel electrophoresis experiment in the presence and absence of an oxidant (H2O2). Active oxygen intermediates such as hydroxyl radicals and hydrogen peroxide generated in the presence of L and complexes 1-3 may act as active species for the DNA scission. The cytotoxicity of the complexes against HepG2 cancer cells was also studied.

Inhibition and recovery of the catalytic activity of bovine serum albumin-capped gold nanoclusters (BSA-AuNCs) is observed for the first time by introduction of cysteine and Hg(2+). The prepared BSA-AuNCs possess highly intrinsic peroxidase-like activity. It can catalyze the oxidation of 3, 3, 5, 5-tetramethylbenzidine by H2O2 to produce a blue colored product. Based on this phenomenon, a new colorimetric assay for rapid, selective and sensitive detection of cysteine and Hg(2+) in aqueous solution has been demonstrated. The interaction process between target molecule and BSA-AuNCs is very fast, so that the whole test can be completed within ten minutes. Moreover, the fabricated colorimetric sensor is simple and cost-effective, without the need of nucleic acid based recognition element and complicated washing, separation and labeling process, thus holds great promise for routine analysis of cysteine and Hg(2+) in real samples.

A new method based on high performance liquid chromatography-electrospray ionization time of flight-mass spectrometry (HPLC-ESI-TOF/MS) was developed for the rapid identification of active compounds in Styela clava and the development of its specific chromatograms. Samples were extracted by ultrasonic-assisted extraction, and the extraction conditions were optimized. The developed HPLC-ESI-TOF/MS method was used to identify the components in Styela clava extract, and a specific chromatogram based on HPLC analysis was established. Ten compounds in Styela clava extract have been primary identified by HPLC-ESI-TOF/MS on-line detection combined with literature review. The result of similarity evaluation for specific chromatograms indicated that the quality of different Styela clava samples was not entirely consistent. This method has the advantages of simple operation, rapid measurement and it is a powerful tool for identification of active components in Styela clava and its quality control.