Bioassay company will tell 52nd Magnetism and Magnetic Materials conference in Florida how it has achieved real-time measurement of magnetic particles in vivo for the first time

Paris, October 30, 2007 - Magnisense, a developer of next generation bioassays for human and animal diagnostics, food safety and environmental protection, announces today that the company will give a talk on a new method of real-time in vivo registration of magnetic particles at MMM'52 in Florida, November 5-9, 2007. The paper is co-authored by Magnisense and the University of Chicago. The company believes the technique will be useful in diagnostics and other areas where bioassays are important.

According to Magnisense researcher Maxim Nikitin, magnetic particles (MP) have become very popular in scientific research as labels. They are stable, unlike fluorescent labels, and safe as compared to radioactive agents. MP can also be used in magnetic drug delivery as driving agents and as heating agents in hyperthermia.

In the talk, Nikitin will describe how a novel, highly sensitive method of registration of MP concentration in biological tissues and blood system has been proposed and achieved. Magnisense believes this is the first time real-time quantitative in-vivo measurements of MP concentration dynamics in blood flow have been performed.

An original BioMag device, which detects MP using their non-linear magnetic properties, was used in the experiments. The device can record a very small relative variation of magnetic susceptibility up to 10-8 at room temperature, providing sensitivity of several nanograms of MP per ml. A catheter that carried the blood flow of a rat passed through the device. After MP injection, the MP concentration in the circulating blood was measured every 3-4 seconds. MP distribution in blood from the injection site and their absorption by organs was observed as increasing and decreasing signals from the device, respectively. The method was also used to evaluate the distribution of MP between the rat's organs. At a small dose of injected MP, the largest concentrations per gram of tissue were observed in the liver and spleen, while it was 8 times smaller in the kidney and almost no MP were found in brain and heart.

Comparison of the method to the radioactive particle detection technique yielded very promising results. MP were synthesized using a radioactive isotope of 59Fe. Rat's blood and organ samples were examined for magnetic and radioactive signals after MP injection. The experiments showed that the sensitivity threshold of the BioMag device is on the same level as that of the radioactive method. The proposed magnetic method is, however, safe and less expensive and provides real-time measurements in vivo. Moreover, its sensitivity can be improved by changing the geometry of the device.

The MMM conference annually brings together scientists and engineers interested in recent developments in all branches of fundamental and applied magnetism. Emphasis is placed on experimental and theoretical research in magnetism, the properties and synthesis of new magnetic materials, and advances in magnetic technology. The program consists of invited and contributed papers. Abstract booklets will be made available at the conference, and the full paper will be published in the Journal of Applied Physics.

About Magnisense http://www.magnisense.com
Magnisense develops next-generation bioassays for human and animal diagnostics, food safety and environmental protection. These innovative immunoassays are based on superparamagnetic bead markers, which deliver the accuracy of laboratory testing with the ease of use of rapid test methods.

Exploiting a unique feature of superparamagnetic bead markers, Magnisense's MIAtekTM technology provides true quantification of a large volume sample. The magnetic signal is free of interference from environmental factors, permitting a more sensitive and reproducible detection than possible with other surface-restricted approaches.

Magnisense is developing two test formats for different application areas:

• MIAstrip(TM): Point of care testing with a single dose, producing objective, quantifiable and traceable results via a portable reader and offering markers for a number of diseases including avian flu, cardiac disease, tetanus, and bacterial, viral, parasitic or mycotic infections.

• MIAflo(TM): Disposable cartridges for detection of bacterial contamination in food products, e.g. Listeria and Salmonella, or in water, e.g. Legionella, with a sensitivity that brings a significant reduction in testing time.

Founded in 2003, Magnisense has raised two rounds of financing for a total of EUR 6 million from Baring Vostok Capital Partners and private investors.
 

For further information, please contact:

Andrew Lloyd & Associates
Andrew Lloyd / Neil Hunter
Tel: +44 1273 675100
allo@ala.com  / neil@ala.com