Sulfobutyl ether derivative of β-cyclodextrin, cross-linked in the presence of antibacterial drug moxifloxacin, forms water-soluble polymeric nanoparticles (50–150 nm in diameter), with highly efficient (up to 85%) encapsulation of the drug. It was shown in this work that in the case of highly cross-linked complex (using hexamethylene diisocyanate) a substantial part of moxifloxacin molecules can be captured by the polymer’s network (i.e. encapsulated in the growing 3D structure) rather than absorbed by the SBECD’s inner cavity. This is accompanied by dramatic changes in moxifloxacin’s release kinetics profile: depending on pH, 30–100% of the drug is released from the polymer network within a week. Whereas in the case of moxifloxacin absorption on pre-synthesized SBECD polymer matrix, 50% release normally occurs within hours. In vitro studies on Escherichia coli demonstrate that the moxifloxacin in highly cross-linked nanoparticle can preserve over 50% of antibacterial activity for at least 7 days, whereas the same amount of free moxifloxacin, as well as its «guest-host» complex with SBECD, is inactive at this time point. The nanoparticles’ ability to adhere to the bacterial cell wall may contribute to the higher activity of the smaller amount of the drug, emphasizing the potential relevance of this approach for the development of new pharmaceutical formulations.
Anna A. Skuredina, Anastasia S. Tychinina, Irina M. Le-Deygen, Sergey A. Golyshev, Natalya G. Belogurova, Elena V. Kudryashova (2021) The formation of quasi-regular polymeric network of cross-linked sulfobutyl ether derivative of β-cyclodextrin synthesized with moxifloxacin as a template. Reactive and Functional Polymers, 159, 104811, https://doi.org/10.1016/j.reactfunctpolym.2021.104811.