Synthesis of Functionalized β-Cyclodextrins

β-Cyclodextrin (βCD), N, N-dimethyl formamide (DMF), and sodium hydride were purchased from Sigma-Aldrich, St. Louis, MO, USA. DMF was distilled under a vacuum. The dried DMF was stored in a dark bottle over calcium hydride. sodium hydride (60% in oil) was dried with hexane. Sodium alginate with low viscosity was purchased from Buchi, Switzerland, and pyromellitic dianhydride (PA) was purchased from Alfa Aesar, Ward Hill, MA, USA. Acetone, acetic acid, and hexane were purchased from Chempur, Piekary Slaskie, Poland. Mono-6-azido-6-deoxy-β-Cyclodextrin (NβCD), Mono-6-amino-6-deoxy-β-Cyclodextrin (AβCD), and blocking the amine group by BOC (BOCAβCD) were synthesized according to the procedure [19 (link)].