Cell encapsulation unit) and N-acetyl-D-glucosamine (acetylated unit). It is derived from the N-deacetylation of chitin and has been used for several applications such as drug delivery, space-filling implants and in wound dressings. However, one drawback of this polymer is its weak mechanical properties and is thus often combined with other polymers such collagen to form a polymer with stronger mechanical properties for cell encapsulation applications. Agarose is a polysaccharide derived from seaweed used for nanoencapsulation of cells and the cell/agarose suspension can be modified to form microbeads by reducing the temperature during preparation. However, one drawback with the microbeads so obtained is
Antimicrobial polymer polymers will have trouble diffusing through the bacterial cell wall and cytoplasm. Thus much effort has been directed towards controlling the molecular weight of the polymer. Most bacterial cell walls are negatively charged, therefore most antimicrobial polymers must be positively charged to facilitate the adsorption process. The structure of the counter ion, or the ion associated with the polymer to balance charge, also affects the antimicrobial activity. Counter anions that form a strong ion-pair with the polymer impede the antimicrobial activity because the counter ion will prevent the polymer from interacting with the bacteria. However, ions that form a loose