Abstract
ABSTRACTCopper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) is promising as a reaction to synthesize functional polymers consisting of 1,2,3‐triazole units. Recently, we reported a series of dense 1,2,3‐triazole polymers of 4‐azido‐5‐hexynoic acid derivatives. Herein, we designed a new water‐soluble dense 1,2,3‐triazole polymer carrying amino acid residues in the side chains, that is, poly(N‐(4‐azido‐5‐hexynoyl)cysteine) (poly(AC)), bearing L‐cysteine as a ligand for metal ions. CuAAC polymerization of a protected monomer followed by deprotection and neutralization yielded the sodium salt of poly(AC) (poly(AC)Na). The adsorption capacity of poly(AC)Na with Cd2+ was investigated with a colorimetric assay. Furthermore, the interactions for poly(AC) with group 12 metal ions (Zn2+, Cd2+, and Hg2+) were investigated using isothermal titration calorimetry (ITC) and transmittance measurements. Utilizing the colorimetric assay data, the Cd2+ adsorption capacity per unit weight of poly(AC)Na was evaluated to be 4–5 mmol g−1, comparable to those of Cd2+ adsorbents reported previously. The ITC data demonstrated that the interactions of poly(AC)Na with Zn2+, Cd2+, and Hg2+ were predominantly exothermic. Based on the ITC data, apparent dissociation constants of interactions were roughly estimated to be in the order of 10−5–10−4 M, which are comparable to those for metal‐binding biomolecules. The transmittance data indicated that the poly(AC)Na/CdCl2 system underwent phase separation.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call