Cationic polymers have been the subject of growing research interest in recent
decades with new applications constantly appearing. They exhibit attractive
physicochemical properties derived from the flexibility of the polymer chain, the formation
of H-bonds, amphiphilic and electrostatic interactions as well as a great potential for being
modified to obtain polymeric species for new applications. Furthermore, the different
polymer architectures that are available include linear, branched and dendrimeric.
According to their origin, cationic polymers can be classified in two general groups: natural
or synthetic. Natural cationic polymers are interesting for therapeutic applications because
they have generally a very good biocompatibility. Improvement in synthetic methods
allows the preparation of cationic polymers with precise control of their properties and
changes, such as the molecular weight distribution, polarity and the degradability of the
chains if necessary. The reports describing antimicrobial, antioxidant, anti-tumoral and
anti-inflammatory properties of cationic polymers have grown exponentially during the last
years. Most of them also show interesting changes in their behaviors produced in response
to stimuli such as pH and ionic strength. All these features make them even more
promising for new biotechnological purposes. The wide range of uses of cationic polymers
extends from industrial processes to a great variety of therapeutic, biomedical and
pharmaceutical claims. In this chapter, we summarize the main properties and biotechnological
applications of cationic polymers.
Keywords: Antimicrobial activity, cationic cellulose, cheese-making, chitosan, drugdelivery,
Eudragit, hydrogels, immunomodulation, virus inactivation, wound healing.
