A Tunable Hydrogel Platform Based on Platinum-Containing Polymeric Arsenicals.

Platinum and arsenic (e.g., cisplatin, AsO) have been used extensively in modern medicine due to their strong anticancer and antimicrobial activities. Here, polymeric arsenical scaffolds with varying As-functionalized acrylamide monomer (AsAm) composition are combined with Pt giving rise to hydrogels (-) with their properties being dependent on the AsAm content. The nature of the Pt-polymer interaction has been thoroughly investigated by H and Pt NMR spectroscopy as well as FT-IR, SEM, XPS, and potentiometric titration suggesting that cross-linking occurs primarily via coordination between oxygen atoms of the pendant arsenic acid group and Pt, while secondary noncovalent interactions are proposed to provide further structural integrity and stability. Importantly, the hydrogels demonstrate potential self-healing properties, while the nature of the cross-linking promotes deep penetration of water into the loosely cross-linked networks. Finally, preliminary qualitative antimicrobial evaluation conducted via disk diffusion assay indicates that is active against Gram-negative (uropathogenic Escherichia coli CFT073 and Escherichia coli K12MG1655) and Gram-positive (Bacillus subtilis and Staphylococcus aureus USA 300 JE2) bacterial strains. Overall, the combination of polymeric arsenical scaffolds with Pt results in the formation of cross-linked networks generating soft, strong, and self-healing hydrogels with tunable stiffness and elasticity and preliminary indications of antimicrobial potential.