Nanocomposites and nanomaterials

Aqueous dispersions based on the structured dextrins
Nahornyak M. 1, Fihurka N. 1, Bendoraitiene J.2, Peciulyte L.2, Rutkaite R.2, Samaryk V.1
1 Department of Organic Chemistry, Lviv Polytechnic National University. S.Bandera Str. 12, Lviv -79013, Ukraine. 
E-mail: figurka.nataliia@gmail.com
2 Department of Polymer Chemistry and Technology, Kaunas University of Technology, Radvilenu Rd. 19, Kaunas 50254, Lithuania

Aqueous dispersions are widely used for various biomedical applications, in particular for drug delivery systems and immunological diagnostics. Such materials should meet several requirements; the most important are non-toxicity and biodegradability. Taking into consideration these requirements, systems based on natural polysaccharides are promising as a majority of natural polysaccharides are tolerant to the human body.
Polysaccharides able to form aqueous dispersions should be spatially structured. To the present day, structured polysaccharides have been widely used for chromatography of various types. Developed synthetic approaches to polysaccharide structuring use toxic substances, therefore, these approaches are not always suitable for the production of materials for medical purposes. Thus, the development of new methods for structuring polysaccharides leading to a product with specified characteristics is highly relevant.
In this work, a novel method for structuring dextrins with N-derivatives of glutamic acid via the Steglich reaction has been developed. Structurization of dextrin leads to the formation of two products: (1) cross-linked dextrin macromolecules able to form dispersions of microhydrogels in water medium and (2) branched macromolecules forming aqueous dispersions with nano-sized particles.
Obtained data allows establishing the dependence of polymer properties on the synthesis conditions; this, in turn, allows obtaining aqueous dispersions with the given properties. The dependence of the dispersed phase size and morphology on the synthesis conditions has been studied.
Biochemical and cytological studies confirmed the absence of toxic properties of the obtained products and products of their biochemical destruction, which allows considering them promising materials for biomedical applications.
This work was supported by the Ministry of Education and Science of Ukraine and the Ministry of Education, Science and Sport of the Republic of Lithuania under grant No 0122U002583