| Abstract
| - The effect of carbohydrates on the swelling of the DMPCLα phase has been studied by small angleX-rayscattering (SAXS) and small angle neutron scattering (SANS). Thecarbohydrates are glucose, oligomers ofglucose (up to n = 5), polymers of glucose (pullulan,M = 45 000), and a hydrophobically modifiedpolysaccharide (cholesteryl−pullulan = CHP). Three regimes ofswelling have been observed: (1) Smallsugars (up to n = 3) penetrate into the aqueous layers ofthe lamellar phase and cause a monotonic swellingof the lamellar phase. (2) Macromolecular carbohydrates aresterically excluded from the aqueous layersand retain some of the water in a coexisting isotropic phase; thiscauses an osmotic compression of thelamellar phase. (3) Hydrophobically modified carbohydrates (CHP)can be introduced into the aqueous layers.The polymer containing lipid phase is a new lamellar phase(Lp), with water thicknesses much larger thanthose observed in the absence of polymer.
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