Liposomes were first used to deliver medicine in pharmaceutical lotions because they are very effective at controlling the release of the active ingredient, but are also very gentle to the skin. Sawyer has applied the same technology to insect repellent to control the release of DEET in its Ultra 30™ products.

Similar to the earlier generation of polymer-based controlled release systems (like 3M® Ultrathon), 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. The liposome base enables Sawyer's 30% DEET lotion to be non-greasy, with little to no odor. Ultra 30™ is also non-staining, resists perspiration, and is effective for up to 11 hours.