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.

Chitosan is one of the promising compounds for use in various fields of medicine. However, for successful application, materials based on it must be insoluble in water and have specified physical and mechanical properties. In this work, we studied the interaction of N-methylolacrylamide (NMA) and chitosan upon concentration of the solutions, both under the action of UV radiation and without it, which results in curing of the polymer matrix. The main products, proposed mechanisms of the crosslinking reaction, and the influence of external conditions on these processes have been revealed using NMR, IR, and UV spectroscopy. It was found that the reaction proceeds along three pathways. The main reactions proceed with the amino groups of chitosan, and the hydroxymethyl and vinyl groups of NMA. Studies have shown that for the formation of insoluble materials based on chitosan, the best content in the initial cast solution is 2 wt% of chitosan at 0.25 wt% concentration of NMA. Films formed from such solutions possessed high strength and deformation characteristics, namely an elastic modulus of about 1500 GPa, a strength of about 30 MPa, and an elongation at break of about 100%.