Sawyer Ultra 30 Liposome-based repellent is the newest advancement in insect repellent technology. It is similar to the earlier generation of polymer-based controlled release systems. Liposomes are used to protect and deliver various active ingredients useful for our health and well-being. They are used in medicines, vitamins, vaccines, and cosmetics. They protect active ingredients by providing a package that is completely safe to our body, and that allows the delivery to take place over a longer period of time. The liposome envelops the DEET and slowly time-releases it as needed, thereby extending the effectiveness of the repellent. Unlike polymers, however, liposomes are a natural compound, which is more comfortable to the skin and easier to wear.