Reactive polysaccharide derivatives : synthesis and investigation of reactivity

To exploit the full potential of these naturally occurring biopolymers, they can be chemically modified. In particular, the hydroxy group, which occurs in all polysaccharides, can be functionalised. Most common reaction is esterification, and less frequently etherification (primarily technical products of cellulose), nucleophilic substitution, and oxidation of the hydroxy group. In recent years, these conventional reactions (which require rather harsh conditions for efficient conversion) have been used for the synthesis of reactive derivatives by attaching reactive/clickable moieties to the polysaccharide backbone. With a deeper understanding of the interaction between function and structure of the polysaccharide and the associated increasingly complex applications in technology and biomedicine, polysaccharide structures with easily adjustable properties are required to accommodate biological functions and physico-chemical properties. As a consequence, synthesis of reactive/clickable PS is a fast-growing field with a variety of biomedical applications such as drug delivery, tissue engineering, bioprinting, and wound healing. The combination of activated/reactive polysaccharide derivatives with successive conversion & click reaction offers different benefits compared to direct functionalisation of the polysaccharide backbone with the entire functional unit. This work presents these benefits and some examples of syntheses.