Synthetic approaches were proposed to the development of hybrid organic-inorganic systems based on giant Keplerate polyoxometalates (POM Mo132), biocompatible polymers, and fluorescent molecules. A concept was formulated for the production of new systems for the prolonged release of drugs bearing a constant or temporary (protonated group) positive charge and fluorescent labels for tissue staining during electrophoretic introduction. In particular, a possibility of covalent functionalization of the POM Mo132 surface by the organosilicon molecules (aminopropyltrimethoxysilane) was shown. A promising procedure of the synthesis of NHS-esters of rhodamine B for the subsequent inclusion into the hybrid system was developed. The kinetic studies of POM destruction in an aqueous medium were carried out. The influence of association of rhodamine B with Mo132 on the character of fluorescence was studied.