A composition comprising a liposome comprising a first phospholipid comprising a C14-C19:0 fatty acid and a C3-C15:0 fatty acid with a c-terminal carboxyl or a carboxaldehyde group; a second phospholipid comprising a C14-C19:0 fatty acid and a C14-C19:0 fatty acid and a sterol. The first phospholipid is preferably a phosphatidylcholine. The second phospholipid is preferably HSPC and the sterol is preferably cholesterol. In some embodiments, the molar ratio of the respective ingredients is 2-3:5-6:2-3; preferably 2:6:2; or 3:5:2, respectively. The invention also relates to the use of this composition in the targeting of M2 macrophages.