The impact of sugar upon bending modulus of charged lipid membranes

The bending modulus of lipid membranes of giant unilamellar vesicle (GUV) is investigated for different concentration of sugar (sucrose/glucose) in physiological buffer using the distribution of vesicles size. Negatively charged lipid 1,2-dioleoyl-sn-glycero-3-phospho-(1’-rac-glycerol) (DOPG) and neutral lipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) were used to prepare the GUV membranes. The values of bending modulus of charged lipid membranes declines with the inflation of sugar concentration. To support this result, the bending modulus of neutral DOPC-GUV membranes is also studied for various sugar concentrations in MilliQ water, which shows a similar trend as obtained in charged GUVs. Therefore, it is concluded that the inflating sugar concentration reduces the bending modulus of vesicle lipid membranes.