ABSTRACT
The use of a double-substituted hydrophobe modified cationic polysaccharide is fundamentally different from commercial vaginal formulations, which rely exclusively on nonionic or anionic vehicles. Cationic and hydrophobe modified polysaccharides are preferred excipients for personal care products since they are substantive to anionic or hydrophobic substrates, hydrophilic, film forming, compatible with many therapeutic agents, nonpenetrating, and non-irritating. Topical spermicides such as nonoxynol-9 and benzalkonium chloride act on sperm membranes through a detergent effect, namely, hydrophobe-hydrophobe interaction between the active and substrate. Hydrophobe modified cationic polysaccharides displayed unique sperm impedance, but not spermicidal, properties. By contrast, the related non-hydrophobe modified material was devoid of that effect. The addition of sulfated polysaccharides to double substituted cationic cellulose ether gels have yielded effective microbicides in vitro, including activity against human immunodeficiency virus. Major efforts are under way to develop new and more effective microbiocides, excipient delivery vehicles, and subsequent formulations.
