Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Navigable Nanotransport

07.02.2007
Direct synthesis of hollow nanoscopic spheres with tailored surfaces

To accurately transport pharmaceutical agents to their specific target organs or cell types, you need a good carrier: nanoscopic capsules with surface elements that can “recognize” the target in question could do the trick.

To date, all methods for the production of such tiny capsules require preorganized structures or “molds” to shape hollow spheres and most methods require a lengthy, tedious synthetic or purification procedure. Korean researchers led by Kimoon Kim have now developed a very simple novel approach for the direct production of polymeric nanocapsules. As described in the journal Angewandte Chemie, this method is generally applicable to any monomers as long as they have a flat core and multiple polymerizable groups at the periphery.

Additionally, if building block are chosen that are able to bind specific (bio)molecules very tightly, the surface of the capsule can be easily decorated with species that are recognized by cells, showing the transporter the way to reach its goal, such as a tumor cell.

... more about:
»Molecules »Sphere »capsule »folic

To demonstrate the power of their new concept, Kim and his team chose rigid, disk-shaped monomers equipped with a ring of special molecular “hooks” that can be activated by UV light. When a solution containing these disks is irradiated, the hooks grab on to each other, linking the disks into little, two-dimensional “patches” that in turn hook on to other patches. Once they reach a certain size, the patches bend around and close off to form hollow spheres, which can then be filled with guest molecules. The size of the spheres is very uniform and depends largely on the solvent in which the linking reaction takes place. The researchers used this method to produce capsules with diameters ranging from 50 to 600 nm.

The little disks used in this process deserve special consideration: Kim and his colleagues chose to use curcurbiturils. These disk-shaped molecules have a cavity at their center. As their shape resembles a hollowed-out pumpkin, this class of compounds was named after the plant genus of pumpkins, the cucurbitaceae. When the mini-pumpkins are linked together, they form an empty sphere with many tiny cavities on its surface. These “pockets” can be filled with certain nitrogen-containing biomolecules, such as spermine, in a very stable fashion.

The Korean researchers coupled spermine to the vitamin folic acid and packed these hybrid molecules into the capsule’s pockets. This gave them capsules with a surface covered with folic acid molecules. What for? Many tumors have a significantly increased number of folic acid receptors on the surfaces of their cells. The folic acid on the capsules docks into these sites and is brought into the interior of the cell. Here, the contents of the capsule, such as an antitumor drug or contrast agent, can be released to selectively attack the tumor or to make an unambiguous diagnosis.

Kimoon Kim | EurekAlert!
Further information:
http://www3.interscience.wiley.com/cgi-bin/jabout/26737/press/200705press.html

Further reports about: Molecules Sphere capsule folic

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>