 Because inclusion compounds of cyclodextrins with hydrophobic molecules are able to penetrate body tissues, these can be used to release biologically active compounds under specific conditions.For example, the Joseph Pitha study showed that when testosterone was complexed with hydroxy-propyl-beta-cyclodextrin (HPBCD), that 95% absorption of testosterone was achieved in 20 minutes via the sublingual route but HPBCD was not absorbed, whereas normally hydrophobic testosterone is absorbed less than around 40% normally via sublingual route.Hydrophilic membrane filtration is used in several industries to filter various liquids.