Bioassay applications using magnetoelectronics to detect and manipulate magnetic nanoparticles
Mark Tondra
Diagnostic Biosensors, LLC, Minneapolis, MN
Date: February 2, 2007, Time: 3:30 pm, Location: W122-D3 Engineering Building 1, The University of Houston
Abstract:
Many biochemical analyses rely on some kind of “tag” or “label” for marking the species being measured. Magnetic micro and nanoparticles are very popular for this because they enable the application of a force at the label level for sorting and concentrating the sample. In addition, micromagnetic sensors can be used to detect and count the number of magnetic particles and from this infer the presence and concentration of the species of interest. These technologies are being developed for use in “lab-on-a-chip” devices. The motivation for this area of study comes from the drive to provide individual users with miniaturized, portable systems that perform some or all of the functions that are usually performed in a central clinical laboratory. This can benefit soldiers, food safety workers, water quality monitors, veterinary medicine, and potentially regular consumers.
This talk will give an overview of magnetoelectronics devices as they are used in bioassay applications. It is assumed that members of the audience have varied backgrounds; including biology, chemistry and magnetics.
Biochemical techniques by which biology can be made “magnetic” by attaching magnetic nanoparticles will be discussed briefly. The design and fabrication of micromagnetic sensors and manipulators, some having microfluidic channels, using semiconductor wafer processing will be described. Then, some results from ongoing development efforts will be presented. These efforts fall into two main categories: 1) detection of biochemical molecules that have been bound to the sensor surface (sometimes called a “sandwich assay”) and 2) detection and manipulation of magnetically labeled species in flow. The first category includes DNA chips, while the second includes cell counters or “cytometers.”
At the end of the presentation, some “stretch” goals will be discussed including: 1) single molecule analysis, and 2) making magnetic beads have “color” by giving them a range of detectable properties.
