Supramolecule: Leader of the Nano-world

Anant Babu Marahatta
Ph.D. student in Chemistry
Tohoku University
Japan

Tailoring “Molecular machine” on the atomic or molecular scale is the current subject of interest in the nano-world. In order to explore the molecular architectures behind it, the first and the foremost motivation came by mimicking the biological systems such as enzymes/catalysts/promoters along with some mechanical devices which leads to supramolecules.

The literal meaning of the supramolecule is “beyond the molecule” and the area of chemistry which mainly concentrates on such system is Supramolecular chemistry. It refers to that sort of molecular system which is made up of a distinct number [more than one] of molecular assemblies. Terms such as molecular self-assembly (1D, 2D & 3D), molecular hierarchy, molecular machine, host-guest chemistry, nanoscience are often associated with this area.

The consideration of the intermolecular [between molecules] interactions and the chemistry involved into it, rather than intramolecular [within molecule], is the major objective of the supramolecular chemistry. In this area, molecule acts as a building block unlike in traditional molecular chemistry [where atom acts as a building block]. In molecular chemistry, the binding forces between the atoms are covalent and ionic. In contrast, the non-covalent interactions such as hydrogen-bonding, dipole-dipole and dipole-quadrupole interactions, van der Waal forces and hydrophilic-hydrophobic interaction are the binding forces which hold the supramolecular assembly together. The following video highlights the procedure of molecules clustering in nanometer range.

The origination of the concept of the molecular machine is also fascinated by the molecular network of the supramolecules as well as their systematic arrays. The molecular rotors, molecular brakes, molecular gears, quantum gyroscopes, molecular ratchets etc. are the recently originated ideas. Some of their practical approaches have already been implemented. 

One of the great achievements of the molecular machine is to find the intercellular viscosity which provides the strongest supporting evidence during medical diagnosis. Similarly, “Quantum gyroscope could reveal Universe’s spin” is another recent attractive scientific finding.

If one could able to control the molecular networks of the supramolecules, their pattern and their chemistry externally either by using some electric/magnetic/photonic stimuli or by adsorbing them one or multi dimensionally at some rigid surface and functionalize, this would be the great boon to the nanoworld. Can we? “Yes we can”.

I would like to see you all as a “driver” of the novel supramolecules.

References:
J.AM.CHEM.SOC. 2008,130, 6672-6673
PhysRevLett.2004, 93,137403 (1-4)
http://www.newscientist.com/article/dn2526
http://en.wikipedia.org/wiki/File:Cucurbituril_gyroscope_AngewChemIntEd_2002_v41_p275_hires.png