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CaCO3 vaterites as components of target drug delivery systems

Successful treatment of the majority of oncological diseases that affect solid organs is related to appropriate use of potent and (to varying degrees) toxic antitumor drugs. In a number of cases, chemotherapy requires the maximum localized action of a drug in the tumor area. The most efficient methods of drug administration are introducing medicinal compounds (MC) directly into the tumor or use of target drug delivery systems. The second method makes it possible to decrease general toxicity of MC, and to reach prolonged therapeutic action due to uniform and time-controlled release of a MC into tumor tissue.

In the present work, we studied behavior of porous spherical СаСО3 vaterites (components of delivery systems for antitumor drugs) in various environments (human blood plasma, rat muscle tissue). It was demonstrated that the studied drug carriers undergo morphological transformations and are destructed with time. In blood plasma, due to ion exchange reactions, vaterites are transformed into gradually disintegrating needle-like structures (as shown by scanning electron microscopy and energy dispersive spectroscopy). Similar processes were observed in muscle tissue: in three days, spheres were transformed into needle-like structures and then underwent complete bioresorption.