One-Pot Photo-Induced Sequential CuAAC and Thiol-Ene Click Strategy for Bioactive Macromolecular Synthesis

Conceptually new one-pot photoinduced sequential click reactions were implemented to yield novel block copolymers with the ability for cell adhesion. Poly(epsilon-caprolcatone) possessing clickable functional groups at the chain ends, namely alpha-alkynyl-omega-alkenyl-poly(epsilon-caprolactone) (A-PCL-MA), was prepared by ring-opening polymerization of epsilon-caprolactone using propargyl alcohol in the presence of stannous octoate at 110 degrees C followed by esterification with methacrylic acid. Azide-functional poly(methyl methacrylate) (PMMA-N-3) was prepared independently by atom transfer radical polymerization (ATRP) followed by an azidation process using sodium azide. Finally, A-PCL-MA was reacted with PMMA-N-3 and N-acetyl-L-cysteine (NAC) in a one-pot process through photoinduced sequential click reactions to furnish desired bioactive block copolymer (PMMA-b-PCL-NAC). A matrix for cell adhesion was then prepared from the yielded block copolymer PMMA-b-PCL-NAC and cell proliferation on the matrix was measured. Cells from the Vero cell line (African green monkey kidney epithelial) were incubated on the matrix, and after 48 h, they showed greater cell proliferation than the commercially available cell culture plates used as comparison.