Grantee Research Project Results
Final Report: SELEX DNA Aptamer Filter for Removal of Pesticides and Chloroaromatics
EPA Contract Number: 68D02033Title: SELEX DNA Aptamer Filter for Removal of Pesticides and Chloroaromatics
Investigators: Bruno, John G.
Small Business: OmniSite BioDiagnostics Inc.
EPA Contact: Richards, April
Phase: I
Project Period: April 1, 2002 through September 1, 2002
Project Amount: $69,992
RFA: Small Business Innovation Research (SBIR) - Phase I (2002) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , SBIR - Monitoring , Small Business Innovation Research (SBIR)
Description:
The purpose of this Phase I research project was to develop a set of DNA aptamers to be used in filters for the removal of organophosphorus insecticides and chloroaromatic pollutants. In particular, OmniSite BioDiagnostics, Inc. (OmniSite) focused its efforts on generating and testing aptamers to the insecticides diazinon and malathion, as well as the ubiquitous wood preservative pentachlorophenol (PCP). Time and funding limitations did not permit OmniSite to complete aptamer generation to the insecticides, but aptamers were generated to two different molecular orientations or recognition sites of PCP.
DNA aptamers are similar to antibodies in that they are high-affinity, specific binding agents, but they are composed of nucleic acids instead of protein. As such, DNA aptamers can be heated to near the boiling point of water and release their bound ligands without degrading or denaturing. Therefore, OmniSite immobilized and used the anti-pollutant-specific aptamers in a filter column to aid in the specific removal of pollutants from drinking water.
Summary/Accomplishments (Outputs/Outcomes):
In OmniSite's initial filter tests, a 9-11 percent increase in glass bead column retention of the pollutant PCP was noted due to the presence of specific anti-PCP aptamers conjugated onto the glass beads as assessed by absorbance at 215 nm (the major PCP absorbance peak). The long chain alkylamine (LCA) glass bead control column retained 63-65 percent of the PCP that was loaded onto the column, but this value consistently rose to 74.4 percent column retention when anti-PCP aptamers were covalently conjugated to the LCA-glass beads.
Conclusions:
Flushing with deionized water that had been heated to 95°C released up to 80.4 percent of the bound PCP from aptamer-glass bead columns. This observation demonstrates that the aptamer filters also should be reusable by heating (perhaps even in a microwave oven) to cause the DNA aptamers to release bound pollutants, followed by flushing with water. Ultimately, OmniSite hopes to develop a low-cost, high-efficacy, regenerable drinking water filter that is commercially available to the public. Foresight Science & Technology also envisions the use of aptamers in large industrial-scale effluent purification systems as a commercially viable market entry point for OmniSite in this area.
Supplemental Keywords:
drinking water, DNA, aptamer, filter, pesticide, pollutant, chloroaromatic, pentachlorophenol, PCP, diazinon, malathion, ligand, long chain alkylamine, purification system, SBIR., RFA, Scientific Discipline, Water, Environmental Chemistry, Health Risk Assessment, Chemistry, Drinking Water, monitoring, Safe Drinking Water, human health effects, systemic evaluation of ligands by exponential enrichment (SELEX), detection, exposure and effects, disinfection byproducts (DPBs), exposure, kinetics, community water system, treatment, aptamer filter, pesticide removal, drinking water contaminants, chloroaromatics, water treatment, other - risk managementThe 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.