PMID- 18498184
OWN - NLM
STAT- MEDLINE
DCOM- 20080804
LR  - 20131121
IS  - 0743-7463 (Print)
IS  - 0743-7463 (Linking)
VI  - 24
IP  - 12
DP  - 2008 Jun 17
TI  - Synthesis and characterization of a new gemini surfactant derived from 
      3alpha,12alpha-dihydroxy-5beta-cholan-24-amine (steroid residue) and 
      ethylenediamintetraacetic acid (spacer).
PG  - 6060-6
LID - 10.1021/la7035218 [doi]
AB  - A new gemini steroid surfactant derived from 
      3alpha,12alpha-dihydroxy-5beta-cholan-24-amine (steroid residue) and 
      ethylenediamintetraacetic acid (spacer) was synthesized and characterized in 
      aqueous solution by surface tension, fluorescence intensity of pyrene, and light 
      scattering (static and dynamic) measurements. These techniques evidence the 
      existence of a threshold concentration (cac), below which a three layers film is 
      formed at the air-water interface. Above the cac, two types of 
      aggregates--micelles and vesicle-like aggregates--coexist in a metastable state. 
      Filtration of a solution with a starting concentration of 2.6 mM (buffer 150 mM, 
      pH 10) allows isolation of the micelles, which have an average aggregation number 
      of 12, their density being 0.28 g cm(-3). Under conditions where only the 
      vesicle-like aggregates are detected by dynamic light scattering, a value of 5.5 
      x 10(4) was obtained for their aggregation number at 30 microM, their density 
      being 6.8 x 10(-4) g cm(-3). At high concentrations, the intensity ratio of the 
      vibronic peaks of pyrene, I1/I3, (=0.68) is very close to published values for 
      deoxycholate micelles, indicating that the probe is located in a region with a 
      very low polarity and far from water. A hypothesis to explain the observed 
      aggregation behavior (small aggregates are favored with increasing gemini 
      concentration) is outlined.
FAU - Alvarez Alcalde, Mercedes
AU  - Alvarez Alcalde M
AD  - Departamento de Quimica Fisica, Facultad de Ciencias, Universidad de Santiago de 
      Compostela, Avenida Alfonso X El Sabio s/n, 27002 Lugo, Spain.
FAU - Jover, Aida
AU  - Jover A
FAU - Meijide, Francisco
AU  - Meijide F
FAU - Galantini, Luciano
AU  - Galantini L
FAU - Pavel, Nicolae Viorel
AU  - Pavel NV
FAU - Antelo, Alvaro
AU  - Antelo A
FAU - Vazquez Tato, Jose
AU  - Vazquez Tato J
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080523
PL  - United States
TA  - Langmuir
JT  - Langmuir : the ACS journal of surfaces and colloids
JID - 9882736
RN  - 0 (3alpha,12alpha-dihydroxy-5beta-cholan-24-amine)
RN  - 0 (Amines)
RN  - 0 (Buffers)
RN  - 0 (Cholic Acids)
RN  - 0 (Micelles)
RN  - 0 (Steroids)
RN  - 0 (Surface-Active Agents)
RN  - 9G34HU7RV0 (Edetic Acid)
SB  - IM
MH  - Amines/*chemistry
MH  - Buffers
MH  - Cholic Acids/*chemistry
MH  - Edetic Acid/*chemistry
MH  - Hydrogen-Ion Concentration
MH  - Micelles
MH  - Microscopy, Electron, Transmission
MH  - Models, Chemical
MH  - Molecular Conformation
MH  - Molecular Weight
MH  - Scattering, Radiation
MH  - Steroids/*chemistry
MH  - Surface Properties
MH  - Surface-Active Agents/*chemical synthesis/chemistry
MH  - Thermodynamics
EDAT- 2008/05/24 09:00
MHDA- 2008/08/05 09:00
CRDT- 2008/05/24 09:00
PHST- 2008/05/24 09:00 [pubmed]
PHST- 2008/08/05 09:00 [medline]
PHST- 2008/05/24 09:00 [entrez]
AID - 10.1021/la7035218 [doi]
PST - ppublish
SO  - Langmuir. 2008 Jun 17;24(12):6060-6. doi: 10.1021/la7035218. Epub 2008 May 23.