COMPARATIVE-STUDY OF THE EFFECTS OF SEVERAL N-ALKANES ON PHOSPHOLIPIDHEXAGONAL PHASES

The effects of a series of normal alkanes (decane, dodecane, tetradeca ne, hexadecane, and octadecane) on the hexagonal H-II structures conta ining dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidyl choline (DOPC) were studied using x-ray diffraction and osmotic stress . The alkanes affect structural dimensions and the monolayer intrinsic curvature and bending modulus. The alkane effects are chain-length de pendent and are attributed to their different distribution within the H-II structure. The data suggest that short-chain alkanes are more uni formly distributed within the H-II hydrocarbon regions and change the curvature and bending modulus of the monolayer, whereas longer-chain a lkanes appear confined more to the interstitial region and do not chan ge the curvature and bending modulus.