The relationship between the structure of the headgroup of sphingolipids and their ability to form complex high axial ratio microstructures

Ceramides with chemically modified polar headgroups were prepared and exami ned for their ability to form complex high axial ratio microstructures (CHA RMS). potential drug delivery vehicles. In general. if the modified ceramid e had either a hydrogen bond donor or acceptor at C-l and C-3. including hy drophobic ol hydrophilic groups attached to C-l microstructures formed. Tol erated groups include amides, esters. sulfonates. and ethers. IF modificati on at C-3 added significant bulk (greater than four carbons: regardless of hydrophilicity). then amorphous aggregates formed. Ceramides with C-l and C -3 bridged through a cyclic structure also made microstructures. By using a sphingolipid with an amine headgroup. CHARMs may be modified covalently af ter formation. (C) 2001 Published by Elsevier Science Ireland Ltd. All righ ts reserved.