Nanocomposite Materials Based on Polylactide and Gold Complex Compounds for Absorbed Dose Diagnostics in BNCT

In this study, approaches to the synthesis of complex compound of gold with cysteine [AuCys](n) for measuring absorbed dose in boron neutron capture therapy (BNCT) were developed. The dependence of the complex particle size on pH were established. Nanocomposite materials based on polylactide containing [AuCys](n) particles with an average size of about 20 nm were obtained using the crazing mechanism. The structure of obtained materials was studied by electron microscopy. The release kinetics of [AuCys](n) from polymer matrix were investigated. Release of [AuCys](n) from the volume of the polymeric matrix had a delayed start—this process began only after 24 h and was characterized by an effective rate constant of 1 μg/h from a 20 mg composite sample. At the same time, in vitro studies showed that the concentration of 6.25 μg/mL was reliably safe and did not reduce the survival of U251 and SW-620 cells.