Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Death by Light

05.10.2009
Nanoparticles as agents for the photodynamic killing of antibiotic-resistant bacteria

The increasing antibiotic resistance of bacteria is a serious problem of our time. Hospital germs in particular have developed strains against which practically every current antibiotic is ineffective.

In the battle against resistant microbes, a team at the University of Münster (Germany) is now pursuing a new approach involving photodynamic therapy, which is a technique that is already being used in the treatment of certain forms of cancer and macular degeneration. Upon irradiation with light, an agent produces oxygen in a special activated form that is highly toxic to cells.

As the researchers led by Cristian A. Strassert and Luisa De Cola report in the journal Angewandte Chemie, they would like to use specially developed nanomaterials that bind specifically to bacterial cells to mark them and kill them under irradiation.

The researchers use nanoparticles made of a special porous material (zeolite L). The particles are modified so they carry a coating of amino groups. These bind preferentially to the surfaces of bacterial cells by means of electrostatic attraction and hydrogen bonds. The researchers put a green fluorescent dye into the channels of the mineral, making the bacteria visible under a fluorescence microscope.

The actual “weapons” are photosensitizers anchored on the surface of the nanoparticles. When these molecules are irradiated with light of the right wavelength, they absorb the light energy and transfer it to oxygen molecules found in the surroundings, for example in infected tissue. The oxygen is excited and enters into what is known as the singlet state, in which it is highly reactive and attacks biomolecules – but only in the immediate area in which the singlet oxygen was generated. In this case, the location is right on the bacterial cell where the mineral particle is bound.

The scientists tested their new light-activated killer particles on antibiotic-resistant cultures of E. coli bacteria. After about two hours of irradiation, the bacteria were almost completely killed off. The team achieved comparable results with a strain of resistant gonococci. Furthermore, the researchers from Münster are also considering this material for the treatment of skin cancer. In this case, the tumor cells could be destroyed upon targeted irradiation with red light.

Author: Luisa De Cola, Westfälische Wilhelms-Universität Münster (Germany), http://www.uni-muenster.de/Physik.PI/DeCola/ldc.html

Title: Photoactive Hybrid Nanomaterial for Targeting, Labeling, and Killing Antibiotic-Resistant Bacteria

Angewandte Chemie International Edition 2029, 68, No. 42, 7928–7931, doi: 10.1002/anie.200902837

Luisa De Cola | Angewandte Chemie
Further information:
http://www.uni-muenster.de/Physik.PI/DeCola/ldc.html
http://pressroom.angewandte.org

Further reports about: Angewandte Chemie Cola Germany bacterial cells death oxygen molecule

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>