We suggested recently a novel approach to making lipid amphiphiles and their colloids pH-sensitive: a protonation-induced conformational switch of the built-in trans-2-aminocyclohexanol moiety. In liposomes, this ring flip loosens packing of the attached lipid tails, leading to contents leakage. Here we report our latest studies on the pH-sensitivity of PEG-grafted liposomes containing various trans-2-aminocyclohexanol-based lipids in their membranes. These liposomes are stable at pH 7.4 and yet release their content in a few seconds in a slightly acidic medium. The triggering pH value depends on the structure of amino-group.
Available at: http://works.bepress.com/xin-guo/14/