BIOTECHNOLOGY AT NANO LEVEL

BIOTECHNOLOGY: New research shows that biomolecules can be manipulated when they are exposed to radiation from a pulsed laser beam. They ’open up’ and can thereby be bonded to microscopic surfaces.

When biomolecules are exposed to a pulsed laser beam something intriguing happens: The molecules ’open up’, and you can start manipulating them. You can move the molecules around and bond them to different surfaces. And above all you can hold protein molecules in position within just a few micrometers. That is nano scale biotechnology. Professor Steffen Petersen and Teresa Neves Petersen at Aalborg University’s Department of Physics and Nanotechnology, made the discovery by serendipity. The spectrum of a certain protein displayed strange properties, which they had a choice of investigating closer or passing over. They chose to look into the phenomenon in the hope of discovering interesting new aspects of the function of proteins.

Diagnosis
Luck was on their side, and they soon realised that what they had discovered could be used for industrial applications. Using laser beams, the proteins could be bonded with high precision on solid surfaces such as glass. Until now it has only been possible to bond proteins to surfaces by chemical methods which leave the molecules in random arrangement and with poor spatial precision. The new methods look highly interesting. The research scientists realised that they would be able to construct small biosensors, no bigger than a few millimetres in size, based on this principle – biosensors that would be able to simultaneously diagnose a number of different diseases including cancer.

Since Light Assisted Immobilization is a basic technology for immobilizing proteins on surfaces, this technology can be used for the production of a large range of products that contain immobilized proteins.

Dense packing
The immobilization of proteins can be spatially controlled since light assisted coupling of biomolecules to a surface can be limited to the focal point of illumination. Present day laser technology allows for focal spots with dimensions of 1 micrometer or less. This permits extremely dense packing of different sensor proteins on multisensor array platforms that are able to test e.g. for different antigens in clinical diagnostics.

Biotechnological process industries already use catalytic proteins (enzymes) that are immobilized on the surface of porous reactor tank matrixes, providing large surface areas with stable biological catalysts that are not dissolved into the process solution or the reaction product. Optimization of immobilization methods is an ongoing task, with light assisted immobilization offering a possible solution.

Food packaging
Coating materials with antimicrobial biomolecules is another as yet unexplored field. Lysozyme is however an antimicrobial enzyme that has been shown experimentally to be adaptable for light assisted immobilization, and immobilized Lysozyme on food packaging materials is thus a possible novel field for development.

The technology, which Steffen Petersen and Teresa Neves Petersen have patented in collaboration with Aalborg University and Novi Invest, will now be commercialised through BioNanoPhotonics A/S, a company which was established in autumn 2003.