Novel types of carborane-carrier hyaluronan derivatives via "click chemistry".

Two new HA derivatives bearing carborane rings were synthesized by click chemistry. The optimal conditions were assessed for the preparation of biocompatible boron carriers, potentially suitable for application in BNCT and capable of targeting the CD44 antigen. The new polymeric samples were characterized by means of NMR-spectroscopy techniques that gave degrees of 17 and 8% for HAAACB and HapACB, respectively. Both HAAACB and HApACB turned out to be nontoxic for colorectal, ovarian and bladder tumor cell lines, to disclose a specific interaction with the CD44 antigen as the native hyaluronan moiety, and to deliver boron-atom concentrations largely sufficient for BNCT therapy when accumulated in cancer cells.