Thermodynamic study of functionalized calix[n]arene and resorcinol[n]arene monolayers spreaded at an aqueous pendant drop

Universidad Nacional del Sur Departamento de Química 8000 Bahia Blanca Argentina
Journal of Inclusion Phenomena (Impact Factor: 1.49). 08/2010; 67(3):343-352. DOI: 10.1007/s10847-009-9715-6


The behavior of insoluble calix[n]arene and resorcinol[n]arene derivatives monolayers were studied through the use of a constant
surface Langmuir balance based on Axisymmetric Drop Shape Analysis (ADSA). In each case, a stable monolayer was obtained and
different transitions (induced for lateral compression) could be identified. Thermodynamic parameters were computed through
two dimensional Clausius–Clayperon equations and used to valuate the monolayer stability. A noticeable reduction of thermodynamic
parameters occurred at highly tested temperatures (328 and 338K) for those compounds that had hydrocarbon tails or benzene
rings attached to one side of macrocyclic rim. Such fact was related to a monolayer rearrangement where the macrocyclic ring
changed from a parallel to a perpendicular orientation. In this orientation the hydrophobic interactions between hydrocarbon
chains and benzene rings were maximized. At highly temperature, where vigorous molecular motion existed, those interactions
were superior to the stabilization effect through hydrogen bond.

KeywordsLangmuir monolayers-Calix[n]arenes-Resorcinol[n]arenes-ADSA-Conformational changes-Thermodynamic

Download full-text


Available from: Juan M. Ruso
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Self-assembly has fascinated many scientists over the past few decades. Rapid advances and widespread interest in the study of this subject has led to the synthesis of an ever-increasing number of elegant and intricate functional structures with sizes that approach nano- and mesoscopic dimensions. Today, it has grown into a mature field of modern science whose interfaces with many disciplines have provided invaluable opportunities for crossing boundaries for scientists seeking to design novel molecular materials exhibiting unusual properties, and for researchers investigating the structure and function of biomolecules. Consequently, self-assembly transcends the traditional divisional boundaries of science and represents a highly interdisciplinary field including nanotechnology and nanomedicine. Basically, self-assembly focuses on a wide range of discrete molecules or molecular assemblies and uses physical transformations to achieve its goals. In this Review, we present a comprehensive overview of the advances in the field of drug self-assembly and discuss in detail the synthesis, self-assembly behavior, and physical properties as well as applications. We refer the reader to past reviews dealing with colloidal molecules and colloidal self-assembly. In the first part, we will discuss, compare, and link the various bioinformatic procedures: Molecular Dynamics and Quantitative Structure Activity Relationship. The second section deals with the self-assembly behavior in more detail, in which we focus on several experimental techniques, selected according to the depth of knowledge obtained. The last part will review the advances in drug-protein assembly. Nature provides many examples of proteins that form their substrate binding sites by bringing together the component pieces in a process of self-assembly. We will focus in the understanding of physical properties and applications developing thereof.
    Full-text · Article · Jan 2014 · Current topics in medicinal chemistry