Researchers from the Department of Chemistry Tin Klačić and Davor Kovačević and a former student on the Department Nikolina Peranić, in collaboration with Borna Radatović from the Institute of Physics, have published their latest results in the journal Colloids and Surfaces A: Physicochemical and Engineering Aspects (IF 5.518), in a paper titled Biocompatible hydroxyapatite nanoparticles as templates for the preparation of thin film polyelectrolyte multilayer nanocapsules.
Thin films called polyelectrolyte multilayers could be formed by alternate adsorption of positively and negatively charged polyelectrolytes. In the case of adsorption on nanoparticles followed by the dissolution of the template, it is possible to prepare hollow polyelectrolyte capsules. In this study focus is on the design, synthesis and characterization of capsules of nanometer dimensions made of nontoxic weak polyelectrolytes, poly(allylamine) and poly(acrylic acid) using fully biocompatible hydroxyapatite nanoparticles as a template. The formation of the polyelectrolyte multilayer was monitored by measuring the electrophoretic mobility of particles. After the optimization of the core decomposition conditions, hollow polyelectrolyte capsules were prepared by dissolution of the template in the presence of HCl. Further characterization was performed using Fourier-transform infrared spectroscopy, energy dispersion X-ray spectroscopy, dynamic light scattering, scanning electron microscopy, and atomic force microscopy. With these techniques, the chemical composition, structure, size, morphology and stability of obtained nanocapsules were determined. It was found that the capsules are of a rather narrow size distribution ranging from 100 to 250 nm with a flexible capsule wall being only a few tens of nanometers thick which is very important in the case of future applications in the field of drug delivery.
The research was performed as a part of the Croatian-Slovenian bilateral research project Modulation of fruit polyphenolic profile by sustainable postharvest physical treatments funded by the Croatian Science Foundation.