Electrical detection of dsDNA and polymerase chain reaction amplification
- 331 Downloads
Food-borne pathogens and food safety-related outbreaks have come to the forefront over recent years. Estimates on the annual cost of sicknesses, hospitalizations, and deaths run into the billions of dollars. There is a large body of research on detection of food-borne pathogens; however, the widely accepted current systems are limited by costly reagents, lengthy time to completion, and expensive equipment. Our aim is to develop a label-free method for determining a change in DNA concentration after a PCR assay. We first used impedance spectroscopy to characterize the change in concentration of purified DNA in deionized water within a microfluidic biochip. To adequately measure the change in DNA concentration in PCR solution, it was necessary to go through a purification and precipitation step to minimize the effects of primers, PCR reagents, and excess salts. It was then shown that the purification and precipitation of the fully amplified PCR reaction showed results similar to the control tests performed with DNA in deionized water. We believe that this work has brought label free electrical biosensors for PCR amplification one step closer to reality.
KeywordsLabel-free Electrical detection PCR DNA Listeria
We acknowledge funding support from a cooperative agreement with Purdue University and the Agricultural Research Service of the United States Department of Agriculture, project number 1935-42000-035, and a sub-contract to the University of Illinois at Urbana-Champaign.
- J. Baker-Jarvis, C. A. Jones and B. Riddle, NIST Tech. Note 1509, (1998)Google Scholar
- Centers for Disease Control, “Centers for Disease Control. "CDC—Estimates of Foodborne Illness Questions and Answers." Updated 19 Apr. 2011. Accessed 05 May 2011 <http://www.cdc.gov/foodborneburden/questions-and-answers.html>
- S.R. Crutchfield, T. Roberts, Food Rev 23.3, 44–49 (2000)Google Scholar
- Y-S. Liu, P.P. Banada, A.K. Bhunia and R. Bashir, Proc. IEEE Sens., art. no. 4716498, 550–553, (2008)Google Scholar
- National Advisory Committee on Microbiological Criteria for Foods, J. of Food Prot 73.6, 1160–1200 (2010)Google Scholar
- R.L. Scharff, The Produce Safety Report Project at Georgetown University. 3 Mar. 2010. Accessed 12 June 2011. <http://www.producesafetyproject.org/media?id=0009>
- S. Tomić, S. Dolanski Babić, T. Vuletić, L. Griparić and R. Podgornik, Phys. Rev. E, 75.2, art. no. 021905, (2007)Google Scholar
- United States Department of Agriculture. “ERS/USDA Data Foodborne Illness Cost Calculator.“ USDA Economic Research Service—Home Page. Updated 28 Dec. 2010. Accessed 03 Apr. 2011. <http://www.ers.usda.gov/data/foodborneillness/>