A preliminary investigation of modified alginates as a matrix for gene transfection in a HeLa cell model

Previous reports have demonstrated the effectiveness of chitosan as a transfection agent. These studies have noted the importance of polysaccharide backbone interactions with the cell surface as well as cationic groups in the transfection process. The present study focuses upon the potential utility of another polysaccharide hydrogel, alginic acid, as a transfection agent. Alginic acid was modified by carbodiimide-mediated linkage of several heterocyclic and aromatic amines to the carboxyl group of the alginate, giving the alginate polycationic characteristics through which binding to nucleic acids could be facilitated. The amines used for this modification include diaminoacridine, thionin, basic fuchsin, acridine yellow, and diaminomethyltriazine. Of all the conjugates tested, basic fuchsin-modified alginate produced the greatest increase in the transfection of a plasmid coding for beta-galactosidase into HeLa cells. These studies demonstrate that other polysaccharide hydrogels can be used as transfection agents, and the structural orientation of the cationic spacer arm is crucial for effective transfection.