Up until now, real-time, remote water quality monitoring for toxins has been very limited, often involving laborious and time consuming processes in order to obtain results.
The microChemLab, officially called microChemLab, is a hand-held "chemistry laboratory." The liquid prototype was designed and built at Sandia/California, while the microChemLab that takes measurements in the gas phase was developed at Sandia/New Mexico.
The California microChemLab identifies proteins by separating samples into distinct bands in seconds to minutes. Separations occur in channels as narrow as a human hair coiled onto a glass chip about the size of a nickel.
One of the main advantages of both units are its portability. Complete with the microChemLab, electronics, and sample collector, both devices weigh approximately 25 pounds. The only external parts of the two sensor technologies are water collectors.
"This on-site monitoring approach would enhance current utility monitoring systems that require water samples to be sent to laboratories for analysis, which sometimes takes days for results," said Wayne Einfeld, who heads the Sensor Development Focus Area within Sandia's Water Initiative.
"Our goal is to place these sensors within utility water systems and use them to quickly determine if the water contains harmful bacteria and toxins."
This technology has the potential for early detection of biological toxins and could prove to be very helpful in maintaining the integrity of the nation's water supplies.
The United States has more than 300,000 public supply water wells, 55,000 utilities, 120,000 transient systems at rest stops or campgrounds, and tens of millions of hydrants.
Up until now, real-time, remote water quality monitoring for toxins has been very limited. With a potential terrorist threat that could see contaminants entering the water supply, the need for complete and quick detection has become more urgent.
New Mexico's microChemLab, is developing a device that detects trihalomethanes, undesirable byproducts of the chlorination process used to control the bacterial content of water. Trihalomethanes, which can form when surface water is treated with chlorine, are carcinogenic and can have adverse liver and kidney effects.
New Mexico's portable unit analyses a sample of water by bubbling air through it and collecting trihalomethanes from that air. The collector is heated, sending the trihalomethanes through a separation column and then over a surface acoustic wave (SAW) detector.
"The collector and the separation column can be purchased off the shelf, but the SAW detector is at the heart of the microChemLab," said Curtis Mowry, principal investigator for the New Mexico project.
"The goal by the end of summer is to replace the commercial separation column with a Sandia microfabricated column made using micro-fabrication technology to reduce the power needed and increase performance," he added.
"Both systems will speed the analytical process and give the utility operator better information in a shorter time period," Einfeld commented.
In addition to routine water quality monitoring, both are expected to be part of early warning systems that can help alert utility operators to intentional contamination events that might occur at vulnerable locations downstream from treatment plants.