Amphiphilic aggregates in aqueous medium: thermal and structural properties and interactions with biologically relevant molecules

• Grant number: 01/11721-3
• Support Opportunities: Research Projects - Thematic Grants
• Start date: February 01, 2003
• End date: December 31, 2008
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Maria Teresa Moura Lamy
• Grantee: Maria Teresa Moura Lamy
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Pesquisadores principais: Lia Queiroz Do Amaral

Abstract

The interest in the study of amphiphilic aggregates is equally related to fundamental research, applied science and technology, For instance, those aggregates can be used as biomimetic systems, or in the industries of petroleum, cosmetics, food and drugs. In the present project, we intend to investigate the behavior of aqueous amphiphilic dispersions as a function of several parameters, such as temperature, pH, ionic strength, and amphiphilic concentration, in different regimes of physical and/or biological relevance. We aim at looking into thermal and structural properties of different amphiphiIic aggregates and their interactions with biologically active molecules, using experimental and theoretical approaches. Several spectroscopic and scattering techniques will be used, in particular, electron paramagnetic resonance, static and time resolved fluorescence, light and x-ray scattering. To monitor the phase transitions of the amphiphilic dispersions, besides the techniques mentioned above, we intend to use differential scanning calorimetry and titration calorimetry. In parallel to the experiments, minimal statistical models will be proposed, related to: 1) fluctuations and polydispersity of the aggregates; 2) the hydrophobic chains' transition, and its effect on both the dispersion charge distribution and the inter-aggregates interaction; 3i) hydration and permeability of water through the aggregates; 4) protein folding in the presence of surfactants; 5) nematic phases (uniaxial and biaxial). (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

M. GIRARDI; W. FIGUEIREDO; N. GUISONI; V. B. HENRIQUES. Tiling in the geometric model for water. Brazilian Journal of Physics, v. 34, n. 1, p. 32-37, 2004-03-00. (01/11721-3)

DUARTE‚ E.L.; OLIVEIRA‚ T.R.; ALVES‚ D.S.; MICOL‚ V.; LAMY‚ M.T.. On the interaction of the anthraquinone barbaloin with negatively charged DMPG bilayers. Langmuir, v. 24, n. 8, p. 4041-4049, 2008. (01/11721-3)

TEMPRANA‚ C.F.; DUARTE‚ E.L.; TAIRA‚ M.C.; LAMY‚ M.T.; DEL VALLE ALONSO‚ S.. Structural Characterization of Photopolymerizable Binary Liposomes Containing Diacetylenic and Saturated Phospholipids. Langmuir, v. 26, n. 12, p. 10084-10092, 2010. (01/11721-3)