Tuesday, November 8, 2011

Tying molecules in knots

Tying molecules in knots [ Back to EurekAlert! ] Public release date: 7-Nov-2011
[ | E-mail | Share Share ]

Contact: Professor Kari Rissanen
kari.t.rissanen@jyu.fi
358-505-623-721
Academy of Finland

A research team headed by Professor David Leigh of the University of Edinburgh (UK) and Academy Professor Kari Rissanen of the University of Jyvskyl (Finland) have made the most complex molecular knot to date, as reported in Nature Chemistry (DOI:10.1038/NCHEM.1193, published online Nov. 6 2011).

Knots can be found in DNA, proteins and even in the molecules that make up man-made plastics, where they often play an important role in the substance's properties (for example, 85% of the elasticity of natural rubber is due to knot-like entanglements in the rubber molecules chains).

However, deliberately tying molecules into well-defined knots so that these effects can be studied is extremely difficult. Up to now, only the simplest type of knot a trefoil knot - had been prepared by scientists. Now Professor David Leigh's team http://www.catenane.net) at the University of Edinburgh together with Academy Professor Kari Rissanen at the University of Jyvskyl have succeeded in preparing and characterizing a more complex type of knot a pentafoil knot (also known as a cinquefoil knot or a Solomon's seal knot) - a knot which looks like a five-pointed star.

Remarkably, the thread that is tied into the star-shaped knot is just 160 atoms in length that is about 16 nanometers long (one nanometer is one millionth of a millimeter). The Edinburgh researchers used a technique known as "self-assembly" to prepare the knot in a chemical reaction. The building blocks are chemically programmed to spontaneously wrap themselves up into the desired knot. Making knotted structures from simple chemical building blocks in this way should make it easier to understand why entanglements and knots have such important effects on material properties and may also help scientists to make new materials with improved properties based on knotted molecular architectures.

###

Further information:

Academy Professor Kari Rissanen, University of Jyvskyl, tel. 358-50-56-23-721, kari.t.rissanen@jyu.fi

Professor David Leigh, University of Edinburgh, tel. 44-131-650-4721, David.Leigh@ed.ac.uk (http://www.catenane.net)

Link to the rotating pentafoil knot (http://users.jyu.fi/~krissane/Knot.html)



[ Back to EurekAlert! ] [ | E-mail | Share Share ]

?


AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


Tying molecules in knots [ Back to EurekAlert! ] Public release date: 7-Nov-2011
[ | E-mail | Share Share ]

Contact: Professor Kari Rissanen
kari.t.rissanen@jyu.fi
358-505-623-721
Academy of Finland

A research team headed by Professor David Leigh of the University of Edinburgh (UK) and Academy Professor Kari Rissanen of the University of Jyvskyl (Finland) have made the most complex molecular knot to date, as reported in Nature Chemistry (DOI:10.1038/NCHEM.1193, published online Nov. 6 2011).

Knots can be found in DNA, proteins and even in the molecules that make up man-made plastics, where they often play an important role in the substance's properties (for example, 85% of the elasticity of natural rubber is due to knot-like entanglements in the rubber molecules chains).

However, deliberately tying molecules into well-defined knots so that these effects can be studied is extremely difficult. Up to now, only the simplest type of knot a trefoil knot - had been prepared by scientists. Now Professor David Leigh's team http://www.catenane.net) at the University of Edinburgh together with Academy Professor Kari Rissanen at the University of Jyvskyl have succeeded in preparing and characterizing a more complex type of knot a pentafoil knot (also known as a cinquefoil knot or a Solomon's seal knot) - a knot which looks like a five-pointed star.

Remarkably, the thread that is tied into the star-shaped knot is just 160 atoms in length that is about 16 nanometers long (one nanometer is one millionth of a millimeter). The Edinburgh researchers used a technique known as "self-assembly" to prepare the knot in a chemical reaction. The building blocks are chemically programmed to spontaneously wrap themselves up into the desired knot. Making knotted structures from simple chemical building blocks in this way should make it easier to understand why entanglements and knots have such important effects on material properties and may also help scientists to make new materials with improved properties based on knotted molecular architectures.

###

Further information:

Academy Professor Kari Rissanen, University of Jyvskyl, tel. 358-50-56-23-721, kari.t.rissanen@jyu.fi

Professor David Leigh, University of Edinburgh, tel. 44-131-650-4721, David.Leigh@ed.ac.uk (http://www.catenane.net)

Link to the rotating pentafoil knot (http://users.jyu.fi/~krissane/Knot.html)



[ Back to EurekAlert! ] [ | E-mail | Share Share ]

?


AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


Source: http://www.eurekalert.org/pub_releases/2011-11/aof-tmi110711.php

x factor auditions flds flds revenge revenge extremely loud and incredibly close boston redsox

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.