Reactive oxygen species generation in aqueous solutions containing GdVO:Eu nanoparticles and their complexes with methylene blue.

It this letter, we report the study of free radicals and reactive oxygen species (ROS) generation in water solutions containing gadolinium orthovanadate GdVO:Eu nanoparticles (VNPs) and their complexes with methylene blue (MB) photosensitizer. The catalytic activity was studied under UV-Vis and X-ray irradiation by three methods (conjugated dienes test, OH· radical, and singlet oxygen detection). It has been shown that the VNPs-MB complexes reveal high efficiency of ROS generation under UV-Vis irradiation associated with both high efficiency of OH· radicals generation by VNPs and singlet oxygen generation by MB due to nonradiative excitation energy transfer from VNPs to MB molecules.

Two-probe microfluorometry estimation of transmembrane potential (ΔΨ(p)) slight changes in individual hepatocytes under short-term hormone action.

Early events in individual hepatocytes of rat activated by adrenaline (10(-6)M) and phenylephrine (10(-5)M) have been investigated by quantitative image microfluorometry and microspectrofluorometry. Cationic DiOC2 and anionic SqSC4 probes have been used for image analysis and transmembrane potential (ΔΨ p) estimation in real-time studies. Fluorescence spectra resulting from the accumulation of dyes in single cells were recorded.

Effect of tilorone and its analogues on the change of mitochondrial potential of rat hepatocytes.

The influence of tilorone dihydrochloride and its analogues--diphenyl derivatives on the changes of transmembrane potential of mitochondrial membranes of the isolated rat hepatocytes has been estimated. Authors have shown a significant increase in mitochondrial potential thirty minutes after the introduction of the test compounds to the cells using the fluorescent probe JC-1. These results indicate the rapid activation with tilorone and its analog--dihydrochloryde 4,4'-bis-[2-(diethylamino)ethoxy]diphenyl--of the RLR signaling pathway.