Fluorescence probe studies of mixed micellar and lyotropic phases formed between an anionic bile salt and a cationic detergent

Journal Article · Wed Jan 26 23:00:00 EST 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100055a024· OSTI ID:5041572

Wu, K; McGown, L B ^[1]

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1. Duke Univ., Durham, NC (United States)

Fluorescent probes, including pyrene, benzo[ghi]perylene (BgP), and perylene, were used to study organized media formed between the anionic trihydroxy bile salt sodium taurocholate (NaTC) and the cationic detergent octyltrimethylammonium bromide (CTAB), over a wide concentration range that includes micellar and lyotropic phases. Solutions of the individual amphiphiles were studied as well. The location of a probe in the mixed micelles was found to depend on the solubility and size of the probe. The microenvironment of pyrene is dominated by NaTC in the mixed micelles, whereas the larger and less soluble perylene and BgP probes interact more favorably with the hydrophobic tails of the CTAB molecules. The photophysical responses of the probes reflect their different locations, providing different perspectives on the transitions in micellar structure. Bromide counterion at the micellar surfaces was found to be an important factor in the photophysical responses, along with accessibility to bulk solution. A scheme for mixed micellization is proposed that extends from large excesses of one amphiphile to large excesses of the other, over a wide range of total amphiphile concentration. Interestingly, the lyotropic phases formed between NaTC and CTAB have high bulk viscosity, but the probe microenvironment is less viscous than in the mixed micellar phases. 43 refs., 9 figs., 2 tabs.

• DOE Contract Number: FG05-88ER13931
• OSTI ID: 5041572
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:4; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
550200 -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ADDITIVES
AGGLOMERATION
AROMATICS
BILE ACIDS
CARBOXYLIC ACIDS
CONDENSED AROMATICS
DETERGENTS
DISPERSIONS
EMISSION SPECTROSCOPY
EMULSIFIERS
FLUORESCENCE SPECTROSCOPY
HYDROCARBONS
HYDROXY COMPOUNDS
MICELLAR SYSTEMS
MIXTURES
ORGANIC ACIDS
ORGANIC COMPOUNDS
PERYLENE
PROBES
PYRENE
SALTS
SOLUTIONS
SPECTROSCOPY
STEROIDS
STEROLS
SURFACTANTS
VISCOSITY
WETTING AGENTS