Nanocomposites and nanomaterials

Synthesis and study of the properties  doped Bioglass 60S composites for bone tissue engineering applications
Kusyak A.P. 1, Gorbyk P.P.1, Dubok V.A.2, Chornyi V.S.3, Bur'yanov O.A.3
1 Chuiko Institute of Surface Chemistry of the NAS of Ukraine.
 General Naumov Str., 17, Kyiv - 03164, Ukraine.
E-mail: a_kusyak@ukr.net
2 Frantsevich Institute of Problems of Materials Science of the NAS of Ukraine.
 Krzhizhanovsky Str., 3, Kyiv - 03142, Ukraine.
3 Bogomolets National Medical University.
 Taras Shevchenko Boulevard, 13, Kyiv - 02000, Ukraine.

The 60S sol-gel glass characterized by osteoconductive properties that depend on the surface structure of the material. The specific surface area of sol-gel glasses (up to 200 m2/g) is much higher than other bioactive ceramics and creates the prerequisites for the adsorption of the necessary organic and inorganic substances on their surface. 
As a result of the hydrolysis of bioactive glass, changing the pH level and active ion-exchange processes leads to an increase in the concentration of Si4+, Ca2+, HPO42-  ions in the biological environment, which can affect on the viability and activity of cell cultures. For La3+, Y3+ the spectrum of therapeutic activities includes apoptosis of cancer cells, decreased rate resorption of bone and bioceramics, selective immunomodulatory activity. In addition, as a result of doping La3+ and Y3+ changes in the specific surface area, due to a decrease in the size of primary crystals, and the formation of active sorption centers on the surface is predicted.
In this work, the samples of 60S glass (4% P2O5, 35% CaO and 60% SiO2) and doped with La (4%), Y (4%) and La 2% +Y 2% was produced. The synthesis was carried out by sol-gel method using: tetraethyl orthosilicate (TEOS), triethyl phosphate (TEP), ethanol, calcium nitrate tetrahydrate, 59 % solution of nitric acid.
Іnvestigated the value of SSA - important characteristic that is regulated by the synthesis conditions and depends on the alloying components and affects the adsorption/desorption processes involving the glass surface. Samples of BG 60S doped 4% La are characterized by an increase in the value of total pore volume to 533 cm3 g-1 and the formation of a microporous structure with values of micropore volume 2.42 mm3g-1 and micropore area 6.86 m2 g-1. Addition of 4% Y or 2% La+2% Y does not lead to the formation of micropores.