Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Nanotube Construction Set

Molecular trees and sugar cuffs are components for nanotubes with tailored surfaces

Organic nanotubes could make rapid strides as functional nanomaterials in a new approach to nanoelectronics and biomedicine, as they can be made of easily varied and modified building blocks.

Researchers led by Chulhee Kim at the Inha University in South Korea have recently developed nanotubes made of dendrons and cyclodextrins. As reported in the journal Angewandte Chemie, they have now successfully functionalized the surfaces of the tubes so that, among other things, they can be used to make biosensors for the detection of a specific protein.

Dendron is the Greek word for tree. Dendrons are tree-shaped branched molecules. Kim and Chiyoung Park selected a molecular “tree” with four long hydrocarbon chains as “branches”. At the end of the “trunk” they attached a pyrene group, a system made of four aromatic carbon rings. In solution, these dendrons come together “branch to branch” to form vesicles, or tiny bubbles. If the researchers add cyclodextrins, which are ring-shaped closed chains of glucose rings, each of these settles around a pyrene group like a cuff. This makes it more favorable for the dendrons to group themselves into long nanoscopic tubes whose surfaces are coated with the cyclodextrin “cuffs”.

What makes this concept into a truly universal construction set is that the cyclodextrins can easily be equipped with a large variety of functional groups, which then dangle out into the solution from the surfaces of the tubes. The team was thus able to attach special groups that like to bind gold nanoparticles. Nanotubes that are densely covered in metal particles could have interesting applications in nanoelectronics.

The pyrene groups on the nanotubes have another special advantage: they fluoresce. This property allows them to be used in the design of biosensors. To demonstrate this concept, the researchers constructed a specific test for the protein avidin. They equipped the surfaces of the nanotubes with biotin, a biomolecule that specifically binds the proteins avidin and streptavidin. If streptavidin bound to gold nanoparticles is added, these bind to the nanotubes by way of the biotin anchors. This brings the gold particles into the vicinity of the pyrene groups, which causes them to interact electronically, “switching off” the fluorescence. If the protein avidin and the gold-bound streptavidin are added, biotin anchors on the surface of the tube preferentially bind avidin. Pyrene groups in the vicinity of avidin fluoresce. The fluorescence quencher gold-strepavidin can only bind to the binding sites not occupied by avidin. The intensity of the fluorescence therefore depends on the avidin concentration.

Author: Chulhee Kim, Inha University, Incheon (South Korea),

Title: Tunable Fluorescent Dendron-Cyclodextrin Nanotubes for Hybridization with Metal Nanoparticles and their Biosensory Function

Angewandte Chemie International Edition 2008, 47, No. 51, doi: 10.1002/anie.200804087

Chulhee Kim | Angewandte Chemie
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>