Grantee Research Project Results
Final Report: Fluorescent Nanoparticle-Aptamer-Magnetic Bead Sensor for Bioterrorism Detection in Water
EPA Contract Number: EPD04027Title: Fluorescent Nanoparticle-Aptamer-Magnetic Bead Sensor for Bioterrorism Detection in Water
Investigators: Bruno, John G.
Small Business: Operational Technologies Corporation
EPA Contact: Richards, April
Phase: I
Project Period: March 1, 2004 through August 31, 2004
Project Amount: $69,918
RFA: Small Business Innovation Research (SBIR) - Phase I (2004) RFA Text | Recipients Lists
Research Category: Watersheds , SBIR - Homeland Security , Small Business Innovation Research (SBIR)
Description:
Some bioterrorism agents cause disease at very low infective doses and their presence can be masked by the environment. Therefore, ultrasensitive detection is required for homeland defense applications. The goals of this research project were to couple DNA aptamers to magnetic beads (MBs) and commercially available fluorescent nanoparticles (quantum dots [QDs]), and investigate the ability to form “sandwich assays” for two species of bacteria (Escherichia coli O111:B4 and Salmonella typhimurium) and staphylococcal enterotoxin B on the MB surface. The QDs were chosen as fluorophores for their high quantum yield, low photobleaching, and potential for multiplexing by monitoring different emission wavelengths. Operational Technologies Corporation (OpTech) ran the assays in multichannel plastic trays with external magnets to pull the MBs along as the sandwich assays formed and purified the target analytes. OpTech plans to miniaturize the trays into plastic microfluidic cartridges that can be coupled to a handheld fluorometer for use in the field to detect waterborne bioterrorism agents or to monitor beaches for evidence of sewage contamination. The handheld detection system would have many other uses, including other types of environmental detection, food safety monitoring, and point-of-care clinical diagnostics.
Summary/Accomplishments (Outputs/Outcomes):
During Phase I, OpTech clearly demonstrated the feasibility of developing a sensitive multianalyte microfluidic cartridge that will incorporate MB antibody-aptamer-QD or MB-aptamer-aptamer-QD sandwich assays. Although not yet definitive because the microfluidic cartridge is still in development, detection limits appear to be in the range of thousands of bacteria and nanograms of biotoxins. Also during Phase I, OpTech developed and tested a breadboard fluorescence reader via its subcontractor, Taboada Research Instruments, that appears capable of at least nanogram detection of QDs.
Conclusions:
This Phase I SBIR research project demonstrated the feasibility of developing MB-based and QD-based sandwich immunoassays or aptamer-based assays for use in plastic cartridges. These assays could be quite sensitive even if quantified by a handheld fluorometer for which there are now commercial examples, such as the Turner Biosystems PicofluorTM. The handheld detector and cartridges could be used to detect entire panels of waterborne bioterrorism agents, foodborne pathogens, or in the analyses of clinical and veterinary samples.
Supplemental Keywords:
Fluorescent nanoparticle-aptamer-magnetic bead sensor, bioterrorism detection, water, quantum dot, microfluidic cartridges, Escherichia coli, Salmonella typhimurium, staphylococcal enterotoxin B, biotoxin, bacteria, nanotechnology, SBIR,, RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Water, TREATMENT/CONTROL, Ecosystem Protection/Environmental Exposure & Risk, Sustainable Industry/Business, Environmental Chemistry, Technology, Analytical Chemistry, Monitoring/Modeling, Environmental Monitoring, New/Innovative technologies, Environmental Engineering, Engineering, Chemistry, & Physics, Drinking Water, nanosensors, homeland security, monitoring, detection, field portable systems, environmental measurement, field portable monitoring, nanotechnology, biopollution, drinking water regulations, community water system, field monitoring, chemical detection techniques, analytical methods, environmental contaminants, biotechnology, fluorescent nanoparticle aptamer magnetic bead sensor, ultrasenstive detection, resonating microsensor, measurement, biosensors, biosensor, drinking water contaminants, drinking water systemThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.