Rapid Concentration, Detection, and Quantification of Pathogens in Drinking WaterEPA Grant Number: R833840
Title: Rapid Concentration, Detection, and Quantification of Pathogens in Drinking Water
Investigators: Hu, Zhiqiang , Lin, Mengshi , Riley, Lela K.
Institution: University of Missouri - Columbia
EPA Project Officer: Klieforth, Barbara I
Project Period: May 1, 2008 through April 30, 2011 (Extended to April 30, 2013)
Project Amount: $600,000
RFA: Development and Evaluation of Innovative Approaches for the Quantitative Assessment of Pathogens and Cyanobacteria and Their Toxins in Drinking Water (2007) RFA Text | Recipients Lists
Research Category: Drinking Water , Water
The hypothesis of this research is that a lanthanum-based concentration method can be combined with spectroscopic-based detection techniques to serve as a complementary means of standard molecular microbiological methods for rapid pathogen determination. The objectives of this research are to: 1) evaluate a lanthanum-based colloidal destabilization method to rapidly concentrate pathogens in water; 2) determine the efficiency of fluorescence-based oxygen microrespirometry in differentiating live/dead pathogens; 3) develop and validate a new SERS-based method for pathogen detection and quantification; and 4) improve pathogen detection using modified concentration and molecular detection methods and compare the detection efficiencies to the Environmental Protection Agency’s (EPA) existing methods with seeded or unseeded drinking water samples.
Key CCL pathogens such as human adenovirus, calicivirus, Helicobacter pylori, and Encephalitozoon cuniculi were selected because they represent the major categories of pathogens (i.e., DNA viruses, RNA viruses, bacteria and fungi) that pose health risks in drinking water. The pathogen recovery efficiency of lanthanum-based method will be compared with those of EPA’s existing methods (e.g., 1MDS filter method) and polyethylene glycol (PEG) precipitation method. A rapid high-throughput live/dead pathogen differentiation method (with 96 microwells) based on respirometric measurements will be developed using time-resolved fluorescence microrespirometry in conjunction with phosphorescent oxygen-sensitive probes. A more sensitive spectroscopic method-SERS coupled with the SERS-active substrates with defined gold nanoparticles for rapid pathogen detection and quantification will be evaluated. The developed concentration and spectroscopic methods will be applied in and/or compared with standard molecular detection methods such as qPCR.
Waterborne pathogens will be rapidly concentrated and detected at low levels by a series of complementary and nondestructive techniques. The lanthanum-based concentration method will greatly improve pathogen detection using EPA’s existing methods and other PCR-based molecular techniques, which will be beneficial to the public water utilities.