Тонкие химические технологии (Aug 2014)
Polyelectrolyte microcapsules modified with nanoscale titanium dioxide for targeted drug delivery
Abstract
Polyelectrolyte microcapsules composed of CaCO3-core and shell polydiallyldimethylammonium polistirolsufonatpolystyrenesulfonate, were obtained by Layer-by-Layer-method. They were modified with nanoscale titanium dioxide with rutile structure and commercial Degussa P25 and Hombikat UV-100. Besides it has been shown that the sample Hombikat UV-100 is better included in the capsule shell because of a largerspecific surface area and the presence of hydrated component in composition of sample. Resistance to UVradiation was tested on the capsules modified with Degussa P25. It has been established that the modification takes place only in the case of "thick" shells with the number of bilayers being x=8. In the case of shells with x=4 there is a destruction of polyelectrolyte capsules during modification. It has been found that the degree of modification of capsules by nanosizedtitanium dioxide depends on the shell thickness (value x) as well as on the surface of nanoscale titanium dioxide samples