Conference Proceeding

Core-shell nanoparticles for drug delivery: structural properties and kinetic of the drug release process

Dr. ImreDékány,
University of Szeged, Hungary

Dr. Imre Dekany was born in Szeged and attended his schools there. In 1970 he graduated as a chemist at the Attila József University and worked at the Department of Colloid Chemistry. He obtained his Doctorate of Chemical Sciences in 1989 and was appointed to Full Professor in 1990. He was DAAD Fellow (1977-78), Humboldt Fellow (1986-87) at the University of Munich and visiting professor in Jülich Research Center, Germany in 1991. Besides the german cooperation he was visiting professor in USA, in 1994 and in Japan, in 1998. He has been the head of the Colloid Chemistry Department (1989-2008); the vice dean of the Faculty of Science (1987-90), vice rector of the Attila József University (1992-94) and vice rector of the University of Szeged (2003-2009). In 2008, he was appointed as the head of the Physical Chemistry Department and later the head of Department of Physical Chemistry and Materials Science. He is or was member/chairman of different Hungarian and international Committees and Editorial Boards. In 2001, he was elected as a correspondent member and in 2007 as a full member of Hungarian Academy of Sciences. Main topics of his research interest are colloid chemistry and nanotechnology. He is the author of more than 480 papers and 25 patents. He was the head of Nanostructured Materials Research Group of the Hungarian Academy of Sciences (1998-2007) and he is the chairman of the Hungarian Academy of Sciences Szeged Regional Committee (2008-2014). He received the Eduard-Raphael-Lisegang Prise (Germany Colloid Society) in 2000, Szilárd Leo Fellowship (ALCOA Foundation) in 2006, Albert Szent-Györgyi prize (Hungarian Government) in 2007, Gabor Denes Prize and “Master teacher” Award in 2009.

Self-assembled 3D nanoscale system like multilayered core-shell nanoparticles were synthetized as carrier systems for controlled drug delivery. Mesoporous silica nanoparticles (SiNPs d=400 nm) and bovine serum albumin (BSA, d=10nm ) were used for ibuprofen (IBU) -as drug molecule- encapsulation. The silica cores were coating with polyelectrolytes to achieve controlled release of the encapsulated drug molecules. Polyethylenimine (PEI) and poly(sodium-4-styrene-sulphonate) (PSS) bind to the silica nanoparticles via electrostatic interactions, just like the PSS bind to the BSA. The size and the zeta potential were investigated by dynamic light scattering (DLS) measurements. The TEM images demonstrated the formation of the core-shell nanoparticles as well. The development of the core-shell nanoparticles were inspected by FTIR experiments. The β-sheet of protein is the determinative for the BSA and for the one-layered core-shell nanoparticles, while in the case of the BSA/IBU and the two-layered composites the protein chain unfolds, the random coil will be the main secondary structure unit. The structural parameters of the core-shell nanoparticles, such the fractal dimensions, pair correlation functions, correlations lengths were determined by small angle X-ray scattering (SAXS). The adsorption of IBU on BSA functionalized gold surface was studied by surface plasmon resonance spectroscopy (SPR) in 2D structure on the surface of a gold chip. The binding isotherms were determined for calculation of the bonded ibuprofen and ketoprofen amount to the BSA protein chain. The kinetic of the drug release was calculated from the SPR curves for determination of the 2D release constant. The IBU release was investigated by a vertical diffusion cell (Franz cell) connected to a spectrophotometer in a flow measuring system as well. The polyelectrolytes, counter to the composites without shells, slow down the release rate of the IBU. 3D kinetic models were used to describe the release mechanism; the silica-, the BSA-based, the one- and the two-layered composites gave good fitting with different models. The results show that these multilayered core-shell nanoparticles are applicable for targeting different drug molecules as carrier systems. The heat of interaction between the protein and drug molecules was measured by titration microcalorimetry using ITC experiments. Knowing the SPR adsorption isotherms and the calorimetric data we can quantitatively characterize the encapsulation of drug molecules into the BSA structure.

Published: 27 April 2017