Water Resources Research Act Program

Details for Project ID 2008ND162B

Rapid and Sensitive Determination of Bacteria in Water using Nanoparticles

Institute: North Dakota
Year Established: 2008 Start Date: 2008-03-01 End Date: 2009-02-28
Total Federal Funds: $14,800 Total Non-Federal Funds: $29,600

Principal Investigators: Julia Xiaojun Zhao

Project Summary: Bacteria can grow or re-grow in distribution systems of drinking water. In fact, potable water is a major source of some bacteria colonization, for example L. pneumophila and E coli. etc. The L. pneumophila in potable water can replicate rapidly and increase in virulence. The British Communicable Disease Surveillance Center reported that 19 of 20 hospital outbreaks of Legionnaires Disease in the United Kingdom from 1980 to 1992 were attributed to the Legionella-contaminated potable water. Given the low infectious dose of pathogenic bacteria, the presence of even a single bacterium in potable water may pose a serious health risk. Therefore, sensitive and rapid detection of bacteria in water is critical. However, the current definitive method for the detection of bacteria is by using the culture of the organism, which requires about 24 hours for bacterial growth. The method is too slow. The PCR-based method can detect bacteria within six hours; but the method requires pre-enrichment of the target bacteria. The objective of this proposal is to develop a rapid and ultra-sensitive method for the specific identification and quantitative determination of pathogenic bacteria in water. The major feature of the proposed method is the employment of fluorescent nanoparticles as target bacteria identifiers that could emit strong fluorescent signals. The method will consist of three major steps. First, the nanoparticles need to react with a specific antibody to form a conjugate of nanoparticle-antibody (NP-Ab). Second, based on the antibody-antigen reaction, the NP-Ab conjugates have to identify target bacteria cells from a sample by attaching the NP-Ab to the bacteria surface antigen. Third, target bacteria need to be qualitatively and quantitatively determined by measuring the fluorescence intensity and wavelength. The project has three goals. Goal 1 of the development of multiple colored nanoparticles has been achieved in the first year (2006). Goal 2 of the determination of target bacterial cells using nanoparticles has been accomplished in the second year (2007). In this years Fellowship, Goal 3, Simultaneous Determination of Multiple Pathogenic Bacteria Using Nanoparticles is proposed.