Real-Time Multi-Parameter Analysis of Pollutants in Stormwater and Other Complex Analyte Matrices Using Electrospray Ionization-Ion Mobility SpectroscopyEPA Contract Number: 68D03067
Title: Real-Time Multi-Parameter Analysis of Pollutants in Stormwater and Other Complex Analyte Matrices Using Electrospray Ionization-Ion Mobility Spectroscopy
Investigators: Coleman, Thomas E.
Small Business: dTEC Systems LLC
EPA Contact: Manager, SBIR Program
Project Period: October 1, 2003 through December 31, 2004
Project Amount: $225,000
RFA: Small Business Innovation Research (SBIR) - Phase II (2003) Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , Ecological Indicators/Assessment/Restoration , SBIR - Monitoring
The adverse affects of stormwater runoff on water quality in the United States have become an increasing concern in recent years. In 1996, the U.S. Environmental Protection Agency reported to Congress that urban runoff was the leading source of pollutants causing water quality impairment related to human activities in ocean shoreline waters and the second leading cause in estuaries across the United States. Historically, the measurement of nutrients and priority pollutant compounds at trace levels in the complex sample matrices typical of stormwater discharges has required time-consuming and expensive offline measurement in laboratories. This Phase II research project is expected to lead to the development of a portable electrospray ionization-ion mobility spectroscopy (ESI/IMS) analytical system that will be broadly applicable to the monitoring of stormwater runoff and combined sewer overflows. It also will be applicable to the monitoring of drinking water treatment systems for arsenic and other contaminants, including biological and chemical toxins. The ESI/IMS instrument to be developed in this research will enable real-time aqueous phase measurement of conventional parameters, such as ammonia, phosphorus, nitrate, and nitrite, as well as a wide range of organic and inorganic compounds, in the field or online, without the need for transportation of samples or complex sample preparation.
The important findings that have been demonstrated in the first 6 months of the Phase I research project include: (1) quantitative detection of many of the chemical species of interest in stormwater at parts per billion and low parts per million levels, (2) a significant improvement in the design of the electrospray ionization component of the ESI/IMS instrument, (3) the response time and stability of the ESI/IMS measurements are very good, (4) multiple analytes in mixtures can be measured quantitatively at the same time, and (5) significantly lower detection limits can be expected by incorporating improved thermal and electronic noise reduction in a prototype instrument design.
Based on these findings, it is believed that dTEC Systems' ESI/IMS instrument will enable the development of a very powerful and cost-competitive analytical field instrument. At an estimated selling price of $10,000 or less, this would compare very favorably to other multiparameter water quality instruments currently on the market. Additional methods to further enhance the capability of ESI/IMS, in terms of detection limits and range of analytes that can be monitored, will be investigated during Phase II, as will the addition of complexing agents with highly specific metal-binding properties and other solvent modifiers.