A Drexel University engineering professor has developed a millimeter-size cantilever biosensor that can detect cells and proteins in trace samples and in only minutes.
The sensor could have wide applications in medical diagnostic testing (prostate cancer), detecting contamination in food products (E. coli bacteria) and monitoring for biothreat agents (anthrax). In medical testing, the sensor can be used to analyze the four most widely tested fluids: blood, urine, sputum and spinal fluid.
Existing conventional tests require 24 hours and a trip to a laboratory to boost the concentration of microbes in a sample to produce findings. The accurate, handheld sensor Dr. Raj Mutharasan, a Drexel chemical engineering professor, has developed over the past six years can yield findings in about 10 minutes.
No direct test for minute amounts of proteins exists on the market. A study published in the April 1, 2007, issue of Analytical Chemistry using Mutharasan's sensor detected E. coli in ground beef at some of the lowest concentrations ever reported.
Results of a preliminary study using the device to detect noninvasively a prostate cancer biomarker in 15 minutes were recently presented by David Maraldo, a Drexel doctoral student in chemical engineering who worked with Mutharasan on the sensor, at the 96th annual meeting of the United States and Canadian Academy of Pathology.
Kishan Rijal, a Drexel doctoral student in chemical engineering, and Gossett Campbell, who received his doctoral degree in chemical engineering from Drexel in 2006, helped develop the sensor. Dr. Fernando U. Garcia, professor of pathology in the Drexel University College of Medicine, provided urine specimens to Mutharasan in testing for prostate cancer.