By G.P. Thomas
Researchers at the Massachusetts Institute of Technology have devised a novel method to conduct biomedical tests by adapting a basic principle of physics.
The premise of the researchers study is the increased resistance offered by water to the movement of a ball immersed in the water for a larger cross-section of the ball. By extending this principle to a microscopic scale, the MIT researchers have come up with a technique that could pave the way for compact, universal biological testing devices.
The researchers used magnetic microscopic beads that can hold biomolecules such as antibodies which enable them to attach themselves to targeted cells or proteins. Beads of this nature are commonly employed in biomedical studies. The critical aspect of their work is in determining a method to get hold of the beads and make them oscillate under the influence of a magnetic field. The dimensions of the beads can be gauged by determining the rate of oscillation. It is this feature that proves useful in biomedical testing. When the microscopic magnetic beads are placed in the biological sample to be tested, the beads increase in size on attaching with the biomolecules. This change in dimensions can be detected by the effect on the oscillation of the beads. Through this method, it is possible to determine the quantity of target biomolecule in a given sample instantaneously without the need for laboratory analysis.
Apart from the quick detection time and the need for smaller samples, a major advantage of this new diagnostic method is the ability to perform a wide variety of tests involving different kinds of proteins by replacing the fluid with beads comprising the appropriate reactant as coating. The researchers are yet to assess the system with actual biological molecules. They have succeeded in establishing proof of concept by demonstrating that the system can detect difference in size between beads attached to biomolecules and beads free of biomolecules.