Soft Matter & Molecular Biophysics Group    

Design and characterization of nanostructured materials

This line is focused on the processing of nanostructured materials. Micro and mesoporous materials have opened many new possibilities for application in novel catalysis, sensors, biomaterials, drug delivery, fuel cells and energy storage. This proposal aims at developing comprehensive methods of design of micro and mesoporous materials and elucidating the fundamental relationships between the molecular structure of the templates and the function of these systems. Also we try to tie the high thermal stability and mechanical strength to the nanoscale structure and to understand the new dimension of control that size and spatial confinement can bring. The biotechnological potential of these materials is to be realized through our ability to tailor stability, pore sizes and very large surface areas.

For questions, comments or suggestions on this research line, please, contact: JuanM.ruso at usc.es

Some references:

  • Tuning morphology of mesoporous titanium oxides through fluorinated surfactants-based systems.  Juan M. Ruso, Elena Blanco, Paula Messina Journal of Porous Materials (2012), Online First DOI: 10.1007/s10934-012-9578-x
  • Biomimetic formation of crystalline bone-like apatite layers on spongy materials templated by bile salts aggregates.  Marcos Fernández-Leyes, Valeria Verdinelli, Natalia Hassan, Juan M. Ruso, Olga Pieroni, Pablo C. Schulz, Paula Messina Journal of Materials Science (2012), Online First DOI:10.1007/s10853-011-6113-4
  • Mimicking Natural Fibrous Structures of Opals by Means of a Microemulsion-Mediated Hydrothermal Method.  Natalia Hassan, Valeria Verdinelli, Juan M. Ruso, Paula V. Messina. Langmuir, 27 (2011), 8905–8912. DOI:10.1021/la201555f

Cyclodextrin based film design

Cyclodextrins (CDs) are cyclic oligosaccharides with a hydrophobic cavity and a polar exterior that makes them soluble in water. α-CDs spontaneously self-assemble in aqueous solution to form nanotubes or nanocolumns that adsorb to the liquid/air interface. The building blocks of such nanotubes are cylinder-shaped α-CD dimers stabilized by a network of H-bonds. As a result, films of empty nanocylinders with a hydrophobic cavity are concentrated at the surface of α-CD aqueous solutions. The spontaneous introduction of the anionic surfactant Sodium Dodecyl Sulfate (SDS) into such cavities strongly modifies the mechanical properties of the surface film as revealed by the sharp change in its viscoelasticity at specific temperature and concentration ranges (J. Phys. Chem. B, 111, 2007, 12625). We propose the use of cyclodextrins as a versatile system for the design of smart films with special properties, taking advantage of their ability to capture and concentrate at the interface a variety of molecules from the liquid phase. Potential applications of such films range from the already reported control of mechanical properties –useful, for instance, in coating materials- to the capture of gas particles or their use as chemical nanoreactors sensitive to electromagnetic radiation, electrostatic fields and the presence of molecules in the solution or at the vapor phase. At the moment only the structure and some mechanical properties of the α-CD+SDS system have been characterized in detail (using microcalorimetry, BAM, AFM, dynamic and equilibrium surface tension as well as viscoelasticity measurements, and MD simulations at both the liquid and the interface). However, no information about the potential films formed by other cyclodextrins, their thickness, either the effect of salt or other solutes including different surfactant molecules, is available. We are currently working in the detalied characterization of these films.

For questions, comments or suggestions on this research line, please, contact: Angel.Pineiro at usc.es

Some references:

  • A Critical Approach to the Thermodynamic Characterization of Inclusion Complexes: Multiple-Temperature ITC Studies of Native CDs with SDS. Pilar Brocos , Xavier Banquy , Norma Díaz-Vergara, Silvia Pérez-Casas, Ángel Piñeiro, Miguel Costas. Journal of Physical Chemistry B , (2011), in press. DOI: 10.1021/jp208740b
  • Similarities and differences between Cyclodextrin-Sodium Dodecyl Sulfate Host-Guest Complexes of Different Stoichiometries: Molecular Dynamics Simulations at Several Temperatures. Pilar Brocos, Xavier Banquy, Norma Díaz-Vergara, Silvia Pérez-Casas, Miguel Costas, Ángel Piñeiro. Journal of Physical Chemistry B, 114 (2010), 12455-12467. DOI: 10.1021/jp103223u
  • A small molecular size system giving unexpected surface effects: α-Cyclodextrin + sodium dodecyl sulphate in water. Jorge Hernández-Pascacio, Xavier Banquy, Silvia Pérez-Casas, Miguel Costas, Alfredo Amigo, Ángel Piñeiro. Journal of Colloid and Interface Science, 328 (2008), 391-395. DOI: 10.1016/j.jcis.2008.09.002
  • Cyclodextrin-Based Self-Assembled Nanotubes at the Water/Air Interface. Jorge Hernández-Pascacio, Cristina Garza, Xavier Banquy, Norma Díaz-Vergara, Alfredo Amigo, Salvador Ramos, Rolando Castillo, Miguel Costas, Ángel Piñeiro. The Journal of Physical Chemistry B, 111 (2007), 12625-12630. DOI: 10.1021/jp076576t
  • On the Characterization of Host-Guest Complexes: Surface Tension, Calorimetry, and Molecular Dynamics of Cyclodextrins with a Non-ionic Surfactant. Ángel Piñeiro, Xavier Banquy, Silvia Pérez-Casas, Édgar Tovar, Abel García, Alessandra Villa, Alfredo Amigo, Alan E. Mark, Miguel Costas. The Journal of Physical Chemistry B, 111 (2007), 4383-4392. DOI: 10.1021/jp0688815

Structural, dynamic and energetic characterization of proteins

Computational molecular dynamics simulations can be employed to provide structural, dynamic and energetic information of relatively small proteins, peptides and peptide aggregates in aqueous solution or at the water/air interfaces, as well as embedded or interacting with membranes. We have been recently working with a variety of membrane proteins and enzimes using computational techniques. Currently, we are studying the triosephosphate isomerase from different species including humans and the parasites Tripanosoma cruzi and Tripanosoma brucei. The aim of our studies is to provide new insight into the behavior of these proteins, that could be useful to design drugs for the treatment of tripanosomiasis. We are also interested in the effect of different mutations of these and other enzymes that are related to different diseases. A large part of our computational studies in this field are usually supported by experimental work provided by our collaborators.

For questions, comments or suggestions on this research line, please, contact: Angel.Pineiro at usc.es

Some references:

  • Exploring the conformational dynamics and membrane interactions of PorB from C. glutamicum: a multi-scale molecular dynamics simulation study.  Ángel Piñeiro, Peter J. Bond, Syma Khalid. BBA-Biomembranes, (2011), DOI:10.1016/j.bbamem.2011.02.015
  • Molecular Dynamics Simulations Reveal Insights into Key Structural Elements of Adenosine Receptors. David Rodríguez, Ángel Piñeiro, Hugo Gutiérrez-de-Terán. Biochemistry, 50 (2011), 4194-4208. , DOI: 10.1021/bi200100t
  • Modelling and molecular dynamics simulation of the human gonadotropin-releasing hormone receptor in a lipid bilayer. Eduardo Jardón-Valadez, Alfredo Ulloa-Aguirre, Ángel Piñeiro. The Journal of Physical Chemistry B, 112 (2008), 10704-10713. DOI: 10.1021/jp800544x
  • Molecular dynamics study of the triosephosphate isomerase from Trypanosoma cruzi in water/decane mixtures. Norma Díaz-Vergara, Ángel Piñeiro. The Journal of Physical Chemistry B, 112 (2008), 3529-3539. DOI: 10.1021/jp7102275

Self-assembled supramolecular structures

Self-assembled supramolecular structures are defined as the particles resulting from the spontaneous association of smaller molecules. Their structure, physicochemical properties and then their potential applications depend on the charge distribution, size and topology of the monomeric building blocks. We are interested in the design and characterization of nanosized supramolecular particles in aqueous solution as a function of the solute(s) composition. Our studies are based on different experimental and theoretical techniques such as light scattering, titration calorimetry, surface tension and molecular dynamics simulations. Typical systems that we have been studying in the bulk of aqueous solutions are host-guest supramolecular complexes, micelles, drug aggregates, peptide aggregates, protein-lipid interactions and membranes. We have also performed several studies of similar systems at water/air interfaces. The specific control of the structure and properties of self-assembled supramolecular nanoparticles would allow a number of interesting applications like drug carriers, new materials, biosensors, artificial catalyzers, or gas stores.

For questions, comments or suggestions on this research line, please, contact: JuanM.ruso at usc.es (for experimental work) or Angel.Pineiro at usc.es (for computational studies)

Some references:

  • Hydrogenated/Fluorinated Catanionic Surfactants as Potential Templates for Nanostructure Design. Natalia Hassan, Juan M. Ruso, Ángel Piñeiro. Langmuir, 27 (2011), 9719–9728. DOI: 10.1021/la2019346
  • On the self-assembly of a highly selective benzothiazole-based TIM inhibitor in aqueous solution. Natalia Hassan, M. Pilar Garate, Tania Sandoval, Luis Espinoza, Ángel Piñeiro, Juan M. Ruso. Langmuir, 26 (2010), 16681-16689. DOI: 10.1021/la102916x
  • Langmuir monolayers of a hydrogenated/fluorinated catanionic surfactant: from the macroscopic to the nanoscopic size-scale. Elena Blanco, Ángel Piñeiro, Reinhard Miller, Juan M. Ruso, Gerardo Prieto, Félix Sarmiento. Langmuir, 25 (2009), 8075-8082. DOI: 10.1021/la900593c
  • Surface films of short fluorocarbon-hydrocarbon diblocks studied by molecular dynamics simulations. Spontaneous formation of elongated hemimicelles. Ángel Piñeiro, Gerardo Prieto, Juan M. Ruso, Pedro V. Verdes, Félix Sarmiento. Journal of Colloid and Interface Science, 329 (2009), 351-356. DOI: 10.1016/j.jcis.2008.10.018

Physicochemical characterization of proteins, protein adsorption to interfaces and protein aggregates

We are currently working with several fibril and globular proteins and also with a number of membrane proteins. We aim to understand the behavior of these systems since their physicochemical properties could be useful in the design of new materials, to build molecular sensors or they are directly related with diseases. We  collaborate with researchers from different institutions in these studies.

For questions, comments or suggestions on this research line, please, contact: JuanM.ruso at usc.es

Some references:

  • Fibrinogen stability under surfactant interaction.  Natalia Hassan, Leandro R. S. Barbosa, Rosangela Itri, Juan M. Ruso. Journal of Colloid and Interface Science, 362 (2011), 118–126. DOI: 10.1016/j.jcis.2011.06.010
  • Investigating the effect of an arterial hypertension drug on the structural properties of plasma protein.  Natalia Hassan, Julia Maldonado-Valderrama, Patrick A. Gunning, Victor J. Morris, Juan M. Ruso. Colloid and Surfaces B: Biointerfacese, 87 (2011), 489–497. DOI: 10.1016/j.colsurfb.2011.06.015
  • Surface Characterization and AFM Imaging of Mixed Fibrinogen-Surfactant Films.  Natalia Hassan, Julia Maldonado-Valderrama, Patrick A. Gunning, Victor J. Morris, Juan M. Ruso. Journal of Physical Chemistry B, 115 (2011), 6304–6311. DOI:10.1021/jp200835j
  • Rheological properties of ovalbumin hydrogels as affected by surfactants addition.  Natalia Hassan, Paula V. Messina, Veronica Dodero, Juan M. Ruso. International Journal of Biological Macromolecules, 48 (2011), 495–500. DOI: 10.1016/j.ijbiomac.2011.01.015
  • Mechanisms of fibrinogen–acebutolol interactions: Insights from DSC, CD and LS.   Natalia Hassan, Juan M. Ruso, Poniseril Somasundaran. Colloids and Surfaces B: Biointerfaces, 82 (2011), 581–587. DOI:10.1016/j.colsurfb.2010.10.020