Superfund Research Program
A Customizable Real-Time Biosensor for Continuous Monitoring of Water Contaminants
Project Leader: Scott W. Cookson
Grant Number: R43ES028993
Funding Period: Phase I: September 2018 - August 2019
- Program Links
Final Progress Reports
Quantitative BioSciences, Inc. (QBI) is developing the first customizable on-line biosensor platform (the “Qube”) that will use a microfluidic device to house many different “sensor strains,” each with the ability to detect a different water contaminant on a continuous basis.
Each spatially isolated strain fluoresces when its specific target is present in the water. The research team has engineered a custom optics and image processing platform that translates these cell signals into quantitative information about the level of each target present. A single microfluidic cartridge can take continuous data for at least a month with no intervention, and data can be transmitted remotely to a user-friendly interface.
Sensor strains are developed using synthetic biology to modify existing or make new cellular response pathways. The research team currently has strains that can detect the following analytes down to their corresponding detection limits (ppb): Arsenic (5), Cadmium (2), Uranium (300), Mercury (1), Lead (30), Nitrate (25), Nitrite (250), Ammonium (250), Phosphate (25).
The technology improves upon the state of the art in on-line sensing in the following ways:
- Monitor for a suite of contaminants simultaneously: the team currently has strains to detect nine different contaminants and have the proven expertise to develop more; the sensor can house over 100 strains at no additional cost.
- Eliminate the need for data interpretation: computational tools are embedded within the sensor to quantitatively correlate cellular fluorescence with toxin concentration.
- Reduce the cost of continuous monitoring: each sensor will cost approximately $5,000 with a $120 monthly cartridge replacement, reducing the cost of continuous, on-line analyzers by over 10-fold.
- Provide real-time quantitative data: the sensor will report continuous concentrations within the relevant range of concern (e.g. arsenic levels can be discerned between 1 and 500 ppb).
- Reduce the effort of the analyst: the sensor will require minimal intervention, as only a monthly swap of the microfluidic cartridge and media/waste containers will be required.
During Phase I of this SBIR project, the research team pursued and completed three Specific Aims related to testing their arsenic, cadmium, and mercury sensor strains, taking many replicates of inductions at several contaminant levels each, and developing quantitative machine learning routines to correlate cellular fluorescence signals with contaminant concentration. They also developed the microfluidic technology to be more robust and user-friendly as well as easy and cheap to produce in mass quantities.
Overall, successful completion of their Phase I Aims led to the development and validation of a water toxin biosensor that can quantitatively sense concentrations of a suite of contaminants in a continuous water stream.