Chemical characterization
of polymer–PCS5 conjugates. (A)
CS–PCS5 final conjugate, (i) schematically represented, (ii) 1H NMR of CS, PCS5, and CS–PCS5 conjugate. Blue arrows
indicate the signals from the aromatic rings and isopropyl groups
of PCS5 and orange arrows the glucosamine units of CS, both observed
in the NMR of the conjugate. (B) HA–PCS5 conjugate (i) schematically
represented, (ii) 1H NMR of HA, PCS5, and HA–PCS5
conjugate. These results corroborated the presence of both the PCS5
characteristic signals (blue arrows) and the acetyl groups of HA (orange
arrows) in the conjugate. Key: CS, chitosan; PCS5, protease cleavage
site 5; HA, hyaluronic acid.