Abstract：
:The homogeneous, single-walled phosphatidylcholine-cholesterol mixed vesicles were prepared by ultrasonic irradiation of egg phosphatidylcholine in the presence of various amounts of cholesterol in solution at 4 degrees under a nitrogen atmosphere followed by molecular sieve chromatography on a Sepharose 4B column. Physicochemical studies performed on these systems invluding sedimentation velocity, diffusion, partial specific volume, intrinsic viscosity, and trapped volume measurements allowed estimation of the weight-average vesicle weight, the vesicle shape, and bilayer membrane thickness of the binary mixture of phosphatidylcholine and cholesterol. Vesicle hydration was calculated using two different methods and the agreement between them was excellent up to cholesterol concentration of 0.32 mole fraction. It was observed that the structural parameters change slowly with increasing cholesterol content up to around 0.3 mole fraction and a relatively abrupt structural alteration occurs above this cholesterol content. This abrupt structural change is consistent with the asymmetrical distribution of lipid composition between the inner and outer bilayer face.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Newman GC,Huang Cdoi
10.1021/bi00686a012subject
Has Abstractpub_date
1975-07-29 00:00:00pages
3363-70issue
15eissn
0006-2960issn
1520-4995journal_volume
14pub_type
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