Article

Gemini surfactants

Journal of Surfactants and Detergents (Impact Factor: 1.52). 09/1998; 1(4):547-554. DOI: 10.1007/s11743-998-0057-8

ABSTRACT The literature, including patents, describing the emerging area of gemini surfactants is reviewed. The differences in structure/property
relationships between gemini and comparable conventional surfactants are described and discussed in terms of their predicted
performance properties. Supportive performance data are enumerated.

0 Bookmarks
 · 
106 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Gemini surfactants are constructed by two hydrophobic chains and two polar/ionic head groups covalently connected by a spacer group at the level of the head groups. Gemini surfactants possess unique structural variations and display special aggregate transitions. Their aggregation ability and aggregate structures can be more effectively adjusted through changing their molecular structures compared with the corresponding monomeric surfactants. Moreover, gemini surfactants exhibit special and useful properties while interacting with polymers and biomacromolecules. Their strong self-aggregation ability can be applied to effectively influence the aggregation behavior of both polymers and biomacromolecules. This short review is focused on the performances of gemini surfactants in aqueous solutions investigated in the last few years, and summarizes the effects of molecular structures on aggregation behavior of gemini surfactants in aqueous solution as well as the interaction of gemini surfactants with polymers and biomacromolecules respectively.
    Physical Chemistry Chemical Physics 02/2011; 13(6):1939-56. · 3.83 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Mesoporous TiO2 nanocrystals have been synthetized by a classical sol-gel route integrated by an hydrothermal growth step using monomeric (dodecylpyridinium chloride, DPC) or dimeric gemini-like (GS3) surfactants as template directing agents. Adsorption isotherms at the solid/liquid interface of the two surfactants have been obtained on aqueous dispersion of titania; the nature of the oxide/adsorbate interactions and the molecules orientation/coarea are discussed. The effects produced by the presence of the two surfactants on the different morphological (surface area, porosity, and shape) and structural (phase composition and aggregate size) features of the final TiO2 samples, calcined at 600∘C, are discussed.
    Journal of Nanomaterials 01/2011; · 1.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Time-resolved fluorescence was applied to characterize the behavior in solution of a gemini surfactant substituted with pyrene (Py-3-12). Upon association in water, excimer formation by Py-3-12 can be probed by acquiring pyrene monomer and excimer fluorescence decays which can be fitted globally according to the model free (MF) analysis to yield quantitative information about the internal dynamics of the Py-3-12 surfactant micelles as well as a complete description of the distribution of the different pyrene species in solution either incorporated inside the micelles or free in solution. A proof of procedure for the MF analysis was established by noting that the concentrations of free surfactant in solution, [Py-3-12](free), was found to equal the critical micelle concentration (CMC) for surfactant concentrations larger than the CMC. (I(E)/I(M))(SPC), the ratio of pyrene monomer to excimer fluorescence intensities, was calculated from parameters retrieved from the MF analysis of the fluorescence decays and was found to be independent of sample geometry. This work demonstrates how time-resolved fluorescence can be used to study the properties of pyrene-labeled macromolecules under conditions where large absorptions and inner filter effects usually distort the steady-state fluorescence signals. It was found that the pyrene excimer is formed mostly by diffusion within the Py-3-12 micelles, which suggests that the pyrene microenvironment is fluid, an important feature for future studies on the interactions of Py-3-12 with DNA.
    Langmuir 02/2011; 27(7):3361-71. · 4.38 Impact Factor

Full-text

View
1 Download
Available from