PMID- 22563986
OWN - NLM
STAT- MEDLINE
DCOM- 20120921
LR  - 20120529
IS  - 1520-5827 (Electronic)
IS  - 0743-7463 (Linking)
VI  - 28
IP  - 21
DP  - 2012 May 29
TI  - Effects of amphiphile topology on the aggregation of oligocholates in lipid 
      membranes: macrocyclic versus linear amphiphiles.
PG  - 8165-73
LID - 10.1021/la301090t [doi]
AB  - A macrocyclic and a linear trimer of a facially amphiphilic cholate building 
      block were labeled with a fluorescent dansyl group. The environmentally sensitive 
      fluorophore enabled the aggregation of the two oligocholates in lipid membranes 
      to be studied by fluorescence spectroscopy. Concentration-dependent emission 
      wavelength and intensity revealed a higher concentration of water for the cyclic 
      compound. Both compounds were shown by the red-edge excitation shift (REES) to be 
      located near the membrane/water interface at low concentrations, but the cyclic 
      trimer was better able to migrate into the hydrophobic core of the membrane than 
      the linear trimer. Fluorescent quenching by a water-soluble (NaI) and a 
      lipid-soluble (TEMPO) quencher indicated that the cyclic trimer penetrated into 
      the hydrophobic region of the membrane more readily than the linear trimer, which 
      preferred to stay close to the membrane surface. The fluorescent data 
      corroborated with the previous leakage assays that suggested the stacking of the 
      macrocyclic cholate trimer into transmembrane nanopores, driven by the strong 
      associative interactions of water molecules inside the macrocycles in a nonpolar 
      environment.
FAU - Widanapathirana, Lakmini
AU  - Widanapathirana L
AD  - Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111, United 
      States.
FAU - Zhao, Yan
AU  - Zhao Y
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20120514
PL  - United States
TA  - Langmuir
JT  - Langmuir : the ACS journal of surfaces and colloids
JID - 9882736
RN  - 0 (Cholates)
RN  - 0 (Lipid Bilayers)
RN  - 0 (Macrocyclic Compounds)
RN  - 0 (Surface-Active Agents)
SB  - IM
MH  - Cholates/chemical synthesis/*chemistry
MH  - Fluorescence
MH  - Lipid Bilayers/chemical synthesis/*chemistry
MH  - Macrocyclic Compounds/chemical synthesis/*chemistry
MH  - Models, Molecular
MH  - Spectrometry, Fluorescence
MH  - Surface-Active Agents/chemical synthesis/*chemistry
EDAT- 2012/05/09 06:00
MHDA- 2012/09/22 06:00
CRDT- 2012/05/09 06:00
PHST- 2012/05/09 06:00 [entrez]
PHST- 2012/05/09 06:00 [pubmed]
PHST- 2012/09/22 06:00 [medline]
AID - 10.1021/la301090t [doi]
PST - ppublish
SO  - Langmuir. 2012 May 29;28(21):8165-73. doi: 10.1021/la301090t. Epub 2012 May 14.