Stability of various PLGA and lipid nanoparticles in temperature and in time and new technology for the preparation of liposomes for anticancer and antibiotic loading

The stabilizer, which is used during the preparation of Poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs), is of great importance for particle properties. It could be shown that the stabilizer affects the PLGA NPs stability in time and in dependence of temperature, which are important parameters for their practical use. Complex nanoparticles were prepared, for which we have used tetrandrine, azithromycin, and tobramycin that were incorporated into nanoparticles of different origin—PLGA nanoparticles and DPPC/DPPA liposomes. The sizes and surface potentials of complex nanoparticles have been determined. The diameters of the obtained nanoparticles were 150–200 nm, and they had surface potentials with different charge and value (for PLGA with PL 10RS and PLGA with PL 35 are − 32.8 and − 22.5 mV, respectively, and for PLGA with DMAB + 15.0 mV). From calorimetric and spectrophotometric studies, the structural stability of complex nanoparticles with drug has been determined. The dependence on temperature and time could be shown. Structural changes of the particles in the temperature interval of 25–40 °C could be observed. It turned out that these transformations for the complex liposomes prepared with DPPC are completely reversible, and for other nanoparticles, these changes are irreversible, which means, that after phase transition, the nanoparticles internal structure restores in a different ways. Furthermore, a method, which allowed to observe the release of drugs from nanoparticles (as for PLGA, also for liposomal nanoparticles) initiated by temperature, was used. The work makes use of a new and fast technology that can be used to produce complex, drug containing liposomes in a one-step procedure.