Chondroitin sulfate

Chitosan (190–310 kDa, degree of deacetylation (DDA): 75–85%), acetic anhydride (>99%), dimethoxyl-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM, >96%), alginic acid sodium salt (70–80 kDa) and hyaluronic acid (15–18 kDa) were purchased from Sigma-Aldrich (St. Louis, MO, USA). 4-Azidobenzoic acid (96%) was obtained from TCI, Ltd. (Tokyo, Japan), and chondroitin sulfate (90%) from Alfa Aesar (Haverhill, MA, USA).

Low viscosity sodium alginate and heparin were obtained from Sigma-Aldrich. Chondroitin sulfate and poly-GalA were obtained from Alfa Aesar. Hyaluronic acid, potassium salt from human umbilical cord, and heparin sulfate were obtained from MP biomedicals and sagent pharmaceuticals, respectively. Poly-GlcA was prepared from Avicel PH-105 NF (FMC Biopolymer) and its structure confirmed by ¹H NMR as described previously [5 (link)]. Poly-ManA, poly-GulA, and poly-MG were prepared via partial acid hydrolysis of sodium alginate, and structure was confirmed by ¹H NMR as described previously [5 (link)]. All prepared polysaccharide samples were dialyzed against 4 L of ddH₂O for 40 h at 4 °C with one buffer exchange, lyophilized, and stored as powders at 4 °C until needed.