PLGA nanoparticles made from drug molecules and method for preparation of gene-carrying nanoparticles

Author: Tamaz Mdzinarashvili
Co-authors: Mariam Khvedelidze, Elene Lomadze, Eka Shekiladze, Nino Shengelia
Keywords: gene-carrying nanoparticles, PAMAM dendrimers, DPPC, PLGA, Calorimeter
Annotation:

Work was carried out successfully, which was dedicated to study the ability to replace damaged genes in cells with the healthy genes. For this purpose, studies were performed at our department. It was selected by us the nanoparticles capable of crossing the cell membrane and penetrating into the cytoplasm and at the same time transporting molecules embedded in their structure. We have prepared PLGA nanoparticles and PAMAM dendrimers with such properties, on the surface of which we were able to bind DNA molecules with length similar to gene. Studies have shown that the DNA/PLGA ratio of 7: 1 (w / w) is optimal to accommodate sufficient length DNA on the surface of one particle. This ratio was determined by physical methods such as centrifugation, spectrophotometry. Also, by using physical methods such are calorimetry, centrifugation, and spectrophotometry, the ratio for PAMAM dendrimers and DNA was determined. Specifically, the ratio of DNA/dendrimers was 43: 3 (w/w). In addition, the environmental conditions (acidity, pH, preparation temperature, etc.) have been further specified for obtain the stable complex nanoparticles with optimal composition. In this regard, we have developed a model image of the complexes nanoparticles and the experimental results are published in the scientific journal with Impact Factor. Work was carried out successfully, which was dedicated to study the ability to replace damaged genes in cells with the healthy genes. For this purpose, studies were performed at our department. It was selected by us the nanoparticles capable of crossing the cell membrane and penetrating into the cytoplasm and at the same time transporting molecules embedded in their structure. We have prepared PLGA nanoparticles and PAMAM dendrimers with such properties, on the surface of which we were able to bind DNA molecules with length similar to gene. Studies have shown that the DNA/PLGA ratio of 7: 1 (w / w) is optimal to accommodate sufficient length DNA on the surface of one particle. This ratio was determined by physical methods such as centrifugation, spectrophotometry. Also, by using physical methods such are calorimetry, centrifugation, and spectrophotometry, the ratio for PAMAM dendrimers and DNA was determined. Specifically, the ratio of DNA/dendrimers was 43: 3 (w/w). In addition, the environmental conditions (acidity, pH, preparation temperature, etc.) have been further specified for obtain the stable complex nanoparticles with optimal composition. In this regard, we have developed a model image of the complexes nanoparticles and the experimental results are published in the scientific journal with Impact Factor. 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.