Microfluidic paper-based aptasensor devices for multiplexed detection of pathogenic bacteria

Authors: SOMVANSHI, S - Purdue University; ULLOA, A - Purdue University; ZHAO, M - Purdue University; LIANG, Q - Purdue University; BARUI, A - Purdue University; LUCAS, A - Purdue University; JADHAV, K - Purdue University; ALLEBACH, J - Purdue University; STANCIU, A - Purdue University

Submitted to: Biosensors and Bioelectronics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/21/2022
Publication Date: 7/1/2022
Citation: Somvanshi, S.B., Ulloa, A.M., Zhao, M., Liang, Q., Barui, A.K., Lucas, A., Jadhav, K.M., Allebach, J.P., Stanciu, A. 2022. Microfluidic paper-based aptasensor devices for multiplexed detection of pathogenic bacteria. Biosensors and Bioelectronics. 207(1):114214. https://doi.org/10.1016/j.bios.2022.114214.
DOI: https://doi.org/10.1016/j.bios.2022.114214

Interpretive Summary: Foodborne illness poses significant public health risks in the US and around the world. Thus, there is a need for more rapid, accurate, and cost-effective methods to detect pathogenic bacteria in foods. To address this need, we have developed a unique, user-friendly device that can detect multiple types of foodborne pathogenic bacteria simultaneously. This pioneering tool uses image analysis to read and measure color changes related to bacterial concentration, providing a quantitative assessment of foodborne pathogen contamination. The latest version is a multiplexed paper-based device that can detect 2 or more foodborne pathogens in lab buffer solution and from samples of real food products. The device has demonstrated its effectiveness in identifying both E. coli O157:H7 and Salmonella Typhimurium, over a broad range of cell concentrations, making it an efficient and reliable tool for food safety. The device's impact is substantial for both public health and the food industry. It enables swift on-site screening of pathogenic bacteria in water and food products, potentially preventing foodborne illnesses and outbreaks. Moreover, its innovative, simple and low-cost design allows for easy production, making it a practical solution for widespread use. Ultimately, this development could lead to improved food safety standards, boosting consumer trust and protecting public health.

Technical Abstract: Foodborne pathogens are major public health concerns worldwide. Paper-based microfluidic devices are versatile, user friendly and low cost. Purdue scientists report a novel paper-based single input channel microfluidic device that can detect more than one whole-cell foodborne bacteria at the same time, and comes with quantitative reading via image analysis. This microfluidic paper-based multiplexed aptasensor simultaneously detects E. coli O157:H7 and S. Typhimurium. Custom designed particles provide colorimetric signal enhancement and false results prevention. Several aptamers were screened and the highest-affinity aptamers were optimized and employed for detection of these bacteria in solution, both in a buffer as well as pear juice. Image analysis was used to read and quantify the colorimetric signal and measure bacteria concentration, thus rendering this paper based microfluidic device quantitative. The colorimetric results show linearity over a wide concentration range (10^2 CFU/mL to 10^8 CFU/mL) and a limit of detection (LOD) of 10^3 CFU/mL and 10^2 CFU/mL for E. coli O157:H7 and S. Typhimurium, respectively. An insignificant change in colorimetric response for non-target bacteria indicates the aptasesnors are specific. The reported multiplexed colorimetric paper-based microfluidic devices is likely to perform well for on-site rapid screening of pathogenic bacteria in water and food products.