An example of a supramolecular assembly reported by Atwood and coworkers in Science 2005, 309, 2037.

An example of a supramolecular assembly reported by Jean-Marie Lehn and coworkers in Angew. Jean-Marie Lehn (born September 30, 1939) is a French Chemist. Chem. , Int. Ed. Engl. 1996, 35, 1838-1840.

A supramolecular assembly or "supermolecule" is a well defined complex of molecules held together by noncovalent bonds. A noncovalent bond is a type of Chemical bond, typically between Macromolecules that does not involve the sharing of pairs of electrons but rather involves more dispersed While a supramolecular assembly can be simply composed of two molecules (e. g. , a DNA double helix or an inclusion compound), it is more often used to denote larger complexes of molecules that form sphere-, rod-, or sheet-like species. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known In Geometry a double helix (plural helices) typically consists of two congruent helices with the same axis differing by a translation In Host-guest chemistry an inclusion compound is a complex in which one Chemical compound (the "host" forms a cavity in which molecules of a The dimensions of supramolecular assemblies can range from nanometers to micrometers. Thus they allow access to nanoscale objects using a bottom-up approach in much fewer steps then a single molecule of similar dimensions.

The process by which a supramolecular assembly forms is called molecular self-assembly. Molecular self-assembly is the process by which Molecules adopt a defined arrangement without guidance or management from an outside source Some try to distinguish self-assembly as the process by which individual molecules form the defined aggregate. Self-assembly is a term used to describe processes in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific local Self-organization, then, is the process by which those aggregates create higher-order structures. Self-organization is a process of Attraction and repulsion in which the internal organization of a System, normally an open system, increases This can become useful when talking about liquid crystals and block copolymers. Liquid crystals are substances that exhibit a phase of matter that has properties between those of a conventional Liquid, and those of a Solid A heteropolymer or copolymer is a Polymer derived from two (or more Monomeric species as opposed to a Homopolymer where only one monomer is

Applications

Supramolecular assemblies are being investigated as new materials in a variety of contexts. For instance, Samuel Stupp and coworkers at Northwestern University showed that a supramolecular assembly of peptide amphiphiles in the form of nanofibers could be used to promote the growth of neurons. ^[1] A great advantage to this supramolecular approach is that the nanofibers will degrade back into the individual peptide molecules that can be broken down by the body.

Another example with implications at the biology/materials science interface is of self-assembling dendritic dipeptides, which form hollow cylindrical supramolecular assemblies in solution and in bulk. Foundations of modern biology There are five unifying principles Materials Science or Materials Engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of Science and Molecular self-assembly is the process by which Molecules adopt a defined arrangement without guidance or management from an outside source The cylindrical assemblies possess internal helical order and self-organize into columnar liquid crystalline lattices. Liquid crystals are substances that exhibit a phase of matter that has properties between those of a conventional Liquid, and those of a Solid When inserted into vesicular membranes, the porous cylindrical assemblies mediate transport of protons across the membrane. ^[2]

Self-assembling dendrons have also been used to generate arrays of nanowires. Molecular self-assembly is the process by which Molecules adopt a defined arrangement without guidance or management from an outside source ^[3] Electron donor-acceptor complexes comprise the core of the cylindrical supramolecular assemblies, which further self-organize into two-dimensional columnar liquid crystaline lattices. Liquid crystals are substances that exhibit a phase of matter that has properties between those of a conventional Liquid, and those of a Solid Each cylindrical supramolecular assembly functions as an individual wire. High charge carrier mobilities for holes and electrons were obtained.

See also

• Molecular self-assembly
• Helicates
• Host-guest chemistry
• Supramolecular chemistry
• Crystal engineering

References

1. ^  Selective Differentiation of Neural Progenitor Cells by High-Epitope Density Nanofibers Gabriel A. Molecular self-assembly is the process by which Molecules adopt a defined arrangement without guidance or management from an outside source Self assembled monolayers ( SAM s are surfaces consisting of a single layer of Molecules on a substrate. DNA nanotechnology is a subfield of Nanotechnology which seeks to use the unique Molecular recognition properties of DNA and other Nucleic acids Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular Molecular self-assembly is the process by which Molecules adopt a defined arrangement without guidance or management from an outside source In Supramolecular chemistry, host-guest chemistry describes complexes that are composed of two or more Molecules or Ions held together in unique Supramolecular chemistry refers to the area of Chemistry that focuses on the Noncovalent bonding interactions of molecules Crystal engineering is the design and synthesis of molecular solid-state structures with desired properties based on an understanding and exploitation of Intermolecular interactions Silva, Catherine Czeisler, Krista L. Niece, Elia Beniash, Daniel A. Harrington, John A. Kessler, Samuel I. Stupp Science Volume 303, Issue 5662, Pages 1352-1355 2004 Abstract
2. ^  "Self-assembly of Amphiphilic Dendritic Dipeptides into Helical Pores" Virgil Percec, Andrés E. Dulcey, Vekatachalapathy S. K. Balagarusamy, Yoshiko Miura, Jan Smidrkal, Mihai Peterca, Sami Nummelin, Ulrica Edlund, Steven D. Hudson, Paul A. Heiney, Hu Duan, Sergei N. Magonov & Sergei A. Vinogradov Nature 2004, 430(7001), 764-768 Abstract
3. ^  "Self-organization of Supramolecular Helical Dendrimers into Complex Electronic Materials" V. Percec, M. Glodde, T. K. Bera, I. Shiyanovskaya, K. D. Singer, V. S. K. Balagarusamy, P. A. Heiney, I. Schnell, A. Rapp, H. -W. Spiess, S. D. Hudson & H. Duan Nature 2002, 419(6905), 384-387.