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The comparative study of influence of lactic and glycolic acids copolymers type on properties of daunorubicin loaded nanoparticles and drug release

Nikolskaya E., Sokol M., Faustova M., Zhunina O., Mollaev M., Yabbarov N., Tereshchenko O., Popov R., Severin E.

Acta of Bioengineering and Biomechanics

2018

Vol. 20, no. 1

65--77

The aim of this study was to compare the physico-chemical and biological properties of polymeric nanoparticles obtained from poly(DL-lactide-co-glycolide) (PLGA) with different ratios of monomers loaded with daunorubicin (DNR). Methods: DNR-loaded nanoparticles (NPs) were prepared with use of modified simultaneous double-emulsion solvent evaporation/diffusion technique. NPs were characterized using dynamic light scattering, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, and differential scanning calorimetry and Fourier transform infrared spectroscopy. Results: NPs with DNR were differing in size and zeta potential, depending on the type of polymer. The data obtained show that total content of DNR correlates with the values of the binding constant of DNR with polymers. The release of DNR from NPs proceeds predominantly for polymers with lower binding constants. The in vitro study of NPs on the MCF-7 cells showed similar activity of particles and substances while for the anthracycline-resistant MCF-7Adr cells the cytotoxicity of the nanoparticles was 3 to 7 times higher depending on the type of copolymer. Conclusions: PLGA DNR-loaded nanoparticles can be used to overcome multidrug resistance (MDR) as well as for reducing the frequency of DNR reception due to the prolonged effect, which allows maintaining the concentration of the drug at the required level. The usefulness of binding constant calculations for obtaining nanoparticles with the maximum drug loading was proven. The rate of drug administration and the frequency of administration can be calculated based on the DNR release profiles and release parameters that depend on polymer type.

Sticking of liquid crystal on photosensitive polymer layers

Gerus I., Glushchenko A., Kurioz Y., Reznikov Y., Tereshchenko O.

Opto-Electronics Review

2004

Vol. 12, No. 3

281-284

The sticking effect on photoaligning surfaces was investigated. We demonstrated that additional irradiation of photoaligning polymers with cinnamoyl side groups with not-polarized UV-light strongly decreases their sticking parameter. We associate this effect with cross-linking of the flexible side-groups by UV light and, as a consequence, with light-induced strengthening of the photoaligning surface. Restriction of mobility of the flexible groups on the photoaligning surface (surface strengthening) resulted in depressing the sticking effect. The method of the decrease of the sticking effect by the light-induced strengthening is rather general, and it can be applied for any photoaligning materials undergoing a light-induced cross-linking of polymer fragments. For poly(vinyl 4-fluorocinnamate) the light-induced strengthening allowed us to get the record value of the sticking parameter, S₀= 0.2%, which is better than traditional rubbed polyimide surfaces provide. Such a value of the sticking parameter along with other aligning characteristics allows considering poly(vinyl 4- fluorocinnamate) as very prospective material for modern liquid crystal display technologies.