Synthesis and characterization of polyampholytic aryl-sulfonated chitosans and their in vitro anticoagulant activity.

•Synthesis and characterization of bioactive sulfonated chitosan through reductive amination reaction has been conducted.•The sulfonate content was controled by the initial reactants ratio and modulated the physicochemical and biological properties of sulfonated chitosan.•Sulfonated chitosan played the role of a polyelectrolyte and exhibits an in vitro anticoagulant activity.