sorbitan-monooleate and thiazolyl-blue

Span 80 (sorbitan monooleate) vesicles behaved differently from conventional phospholipid vesicles (liposomes) because the former had a more fluid interface. After doxorubicin hydrochloride (DOX) was encapsulated into the Span 80 vesicle (loading efficiency: 63 %), DOX-loaded Span 80 vesicles (DVs) were thereafter added to Colon 26 cells. It was suggested, from the flow cytometric analysis and confocal laser microscopic observation, that DVs directly deliver DOX into the cytoplasm of Colon 26 cells. DVs showed the different delivery manner from the DOX-loaded liposomes (DLs). It is considered that the difference of delivery manner between DVs and DLs resulted in the difference of cytotoxicity (IC(50)); i.e. IC(50) values for DVs and DLs were 5 and > 30 μM, respectively. The results obtained herein would give the fundamental findings which can contribute to the improvement of formulation of conventional liposome-based carrier and its cytotoxicity.

Topics: Animals; Cell Culture Techniques; Cell Line, Tumor; Colonic Neoplasms; Doxorubicin; Drug Delivery Systems; Female; Flow Cytometry; Hexoses; Liposomes; Mice; Microscopy, Confocal; Microscopy, Electron, Transmission; Tetrazolium Salts; Thiazoles; Transport Vesicles

The urgent need for toxicological studies on carbon nanotubes (CNTs) has arisen from the rapidly emerging applications of CNTs well beyond material science and engineering. In order to provide a basis for comparison to existing epidemiological data, we have investigated CNTs at various degrees of agglomeration using an in vitro cytotoxicity study with human MSTO-211H cells. Non-cytotoxic polyoxyethylene sorbitan monooleate was found to well-disperse CNT. In the present study, the cytotoxic effects of well-dispersed CNT were compared with that of conventionally purified rope-like agglomerated CNTs and asbestos as a reference. While suspended CNT-bundles were less cytotoxic than asbestos, rope-like agglomerates induced more pronounced cytotoxic effects than asbestos fibres at the same concentrations. The study underlines the need for thorough materials characterization prior to toxicological studies and corroborates the role of agglomeration in the cytotoxic effect of nanomaterials.

Topics: Asbestos, Crocidolite; Carbon; Cell Line, Tumor; Cell Survival; DNA; Hexoses; Humans; Materials Testing; Nanotubes; Polyethylene Glycols; Spectroscopy, Near-Infrared; Tetrazolium Salts; Thiazoles