Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

Water-soluble copolymers of p-methacrylamidobenzoic acid (MABA) with neutral comonomers (N-vinylpyrrolidone (VP), N-methyl-N-vinylacetamide (MVAA), N-methacryloyl glucosamine (MAG)) and anionic comononer sodium styrene sulfonate (NaSS) were synthesized by radical copolymerization. The interactions between the prepared copolymers and Tb³⁺ ions in aqueous solutions were studied; the significant influence of chemical structure of a comonomer on luminescence intensity of Tb³⁺ complexes with the copolymers was revealed. The luminescence intensity of Tb³⁺ complexes with the copolymers containing N-vinylamide units (VP, MVAA) is three times more intense than that observed for the complexes between Tb³⁺ and MAG-containing copolymers. In the case of NaSS-containing copolymers, the luminescence intensity is controlled by the values of binding constants between Tb³⁺ and MABA and the content of MABA units in a copolymer. The studied copolymers and their complexes with Tb³⁺ have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.