Saturday, August 27, 2011

Detecting Infectious Particles

Different microbes can cause many of the same symptoms so in order to make an accurate diagnosis and identify a particular strain, it is very important to have access to all of the information needed. Current tests used for diagnostic purposes are not well suited for use at the point-of-care whether in the doctor’s office or at the local clinic because they require skilled laboratory personnel to perform the tests and it can take up to several days to get results.

Postdoctoral fellow Scott Ferguson at the University of California, Santa Barbara is working with his research advisor H.Tom Soh and other colleagues on a system that would be able to integrate three laboratory processes on a single disposable chip and accurately identify a microbe at the point-of-care. This research is being supported by the NIH’s National Institute of Biomedical Imaging and Bioengineering (NIBIB) and the Army Research Office.

The system under development is called “Magnetic Integrated Microfluidic Electrochemical Detector” or (MIMED). The device combines sample preparation and electrochemical readouts to detect viruses directly from patient samples.

The device is capable of detecting pathogens in a variety of complex biological samples, such as blood, urine, or saliva. By using multiple sensors, the chip could be adapted to detect a broad range of microbes and simultaneously detect several different microbes in the same sample. In cases where a patient displays symptoms common to multiple diseases, this single test would be very helpful in determining the actual cause of the disease, and could be useful in monitoring food and water safety, forensics, and the environment.

According to Ferguson, “In the future, researchers expect the MIMED chip to include an instrument that would integrate pumps, heaters, tubing, and other elements of the system. The disposable chip would then be part of an instrument to handle all sample preparation without any human involvement and may actually cost less than a dollar to manufacture.”