Dark cytotoxicity of submicrometer vaterite particles loaded with photosensitizer Fotoditazin and the vaterite-based core – shells structures

Photodynamic therapy (PDT) is based on the use of photosensitizers together with a light at the wavelength corresponding to its absorption maximum. Photosensitizers are able to generate reactive oxygen species under the visible or infrared light irradiation. They are broadly used for the treatment of cancer and infections due to their physical and chemical properties. Dose-dependent light induced cytotoxicity of photosensitizers shows the strong relation between its concentration in the treatment area and PDT efficiency. With this regard, the development of novel carriers for targeted delivery of photosensitizers is a very prospective research direction, as allows for the enhancement of the local drug concentration in the treatment area and the reduction of the incidental dark toxicity in healthy tissue associated with a classic PDT. Mesoporous vaterite particles are considered as a promising tool for biomedical application due to their biodegradability, high payload ability, as well as to the simplicity and cheapness of their fabrication. The efficiency of vaterite carrier application for a PDT delivery system design has been previously demonstrated. With this regard, the current study was aimed at the evaluation of dark cytotoxicity of the submicron vaterite particles and the vaterite-based core-shells, both loaded with Fotoditazin® photosensitizer.