Studies of the ethanol-induced interdigitated gel phase in phosphatidylcholines using the fluorophore 1,6-diphenyl-1,3,5-hexatriene.

Journal Article (Journal Article)

It is now well established that a number of amphiphilic molecules such as ethanol can induce the formation of the fully interdigitated gel phase in phosphatidylcholines. We have shown earlier that alcohols such as ethanol induce biphasic melting behavior in phosphatidylcholines [Rowe, E. S. (1983) Biochemistry 22, 3299-3305] but not in phosphatidylethanolamines [Rowe, E. S. (1985) Biochim. Biophys. Acta 813, 321-330]. Simon and McIntosh [(1984) Biochim. Biophys. Acta 773, 169-172] showed that the alcohol-induced biphasic melting behavior in phosphatidylcholines is a consequence of acyl chain interdigitation. In the present study we demonstrate the detection of the transition of DPPC and DSPC to the interdigitated phase in the presence of ethanol using the fluorescence properties of the commonly used fluorophore 1,6-diphenyl-1,3,5-hexatriene (DPH). By correlating fluorescence and X-ray diffraction results, we have demonstrated the use of fluorescence to study the phase transition from the noninterdigitated to the interdigitated phase. Using this method, we have investigated the temperature and ethanol concentration dependence of the induction of the interdigitated phase in DSPC and DPPC and shown that the induction of interdigitation by ethanol is temperature dependent, with higher temperature favoring interdigitation. The temperature-ethanol phase diagrams have been determined for DPPC and DSPC.

Full Text

Duke Authors

Cited Authors

  • Nambi, P; Rowe, ES; McIntosh, TJ

Published Date

  • December 27, 1988

Published In

Volume / Issue

  • 27 / 26

Start / End Page

  • 9175 - 9182

PubMed ID

  • 3242621

International Standard Serial Number (ISSN)

  • 0006-2960

Digital Object Identifier (DOI)

  • 10.1021/bi00426a015


  • eng

Conference Location

  • United States