TY - JOUR
T1 - Determination of ethanol partition coefficients to the interior and the surface of dipalmityl-phosphatidylcholine liposomes using deuterium nuclear magnetic resonance spectroscopy
AU - Kreishman, George P.
AU - Graham-Brittain, Cindy
AU - Hitzemann, Robert J.
N1 - Funding Information:
Partial funding for purchase of the NMR was provided by a grant from the National Science Foundation (CHE-8102974). This work was supported in part by a grant from the Scottish Rite Schizophrenia Program.
PY - 1985/7/16
Y1 - 1985/7/16
N2 - The binding of ethanol-d6 to dipalmityl-phosphatidylcholine liposomes (DPPC) can be separated into two processes, namely, ethanol in the bilayer and on the surface of the bilayer. For the deuterons of the methylene group, the T2 of both bound states is shorter than the respective preexchange lifetime (τB) and therefore the amount of ethanol bound to both sites can be determined from the decrease in the methylene intensity resonance in the presence of DPPC. For the methyl resonance, however, only the T2 of deuterons on ethanol bound to the surface is less than its τB and the amount of surface bound ethanol-d6 can be determined. Subtraction yields the amount of ethanol bound within the bilayer. The partion coefficient for internally bound ethanol remains constant from 0 to 3.5 m ethanol. Surface binding is, however, highly cooperative.
AB - The binding of ethanol-d6 to dipalmityl-phosphatidylcholine liposomes (DPPC) can be separated into two processes, namely, ethanol in the bilayer and on the surface of the bilayer. For the deuterons of the methylene group, the T2 of both bound states is shorter than the respective preexchange lifetime (τB) and therefore the amount of ethanol bound to both sites can be determined from the decrease in the methylene intensity resonance in the presence of DPPC. For the methyl resonance, however, only the T2 of deuterons on ethanol bound to the surface is less than its τB and the amount of surface bound ethanol-d6 can be determined. Subtraction yields the amount of ethanol bound within the bilayer. The partion coefficient for internally bound ethanol remains constant from 0 to 3.5 m ethanol. Surface binding is, however, highly cooperative.
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U2 - 10.1016/0006-291X(85)90417-6
DO - 10.1016/0006-291X(85)90417-6
M3 - Article
C2 - 3839669
AN - SCOPUS:0022358125
SN - 0006-291X
VL - 130
SP - 301
EP - 305
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -