Biocompatible copoly(urethane-imide)s containing flexible aliphatic blocks modified with castor oil

Biocompatible copoly(urethane-imide)s with and without castor oil triglyceride fragments in the macromolecules were synthesized using aliphatic polydiol and castor oil as monomers, aromatic diisocyanate, aromatic diamine, and aromatic dianhydride. The copolymers were studied by IR spectroscopy, thermogravimetry (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis; the strength and deformation properties of samples in the form of films were investigated. It was shown that the copolymers exhibit the properties of highly heat-resistant elastomers (τ ₅ up to 294–322°С, tensile strain ε, up to1275%). Cytotoxicity of the copoly(urethane-imide) films that have been previously exposed to several organic solvents was assessed using the methyl tetrazolium test (MTT). The results of the MTT test revealed no cytotoxicity for the films soaked in all selected solvents, while the films not subjected to treatment with solvents demonstrated a noticeable toxic effect toward cultured cells. The viability of fibroblasts cultured in the presence of the nutrient medium obtained after incubation with these non-treated films decreased by more than 60% compared to the control sample (cells cultured under standard conditions).