Organic Geochemistry Research Laboratory

Laboratory Methods and Resources

Laboratory methods include the following: (1) to develop new methods for the laboratory analysis of pesticides, pharmaceuticals, and the degradation products of the parent compounds in environmental samples; and (2) to acquire state-of-the-art laboratory instrumentation for high-quality research and reproducible data.

The goals of the laboratory are to develop, automate, and simplify analytical methods for pesticides, pharmaceuticals, and their degradation products in soil and water. These methods include the use of: solid-phase extraction (SPE), gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), liquid chromatography/tamdem mass spectrometry (LC/MS/MS), and enzyme-linked immunosorbent assay (ELISA).

Laboratory instrumentation currently in use include the following:

• Accelerated Solvent Extractor (ASE)
• Automated Solid-Phase Extraction (SPE)
• Flash Chromatography
• Freeze Drier for Making Standards
• Gas Chromatograph/Mass Spectrometer (GC/MS)
• Kinetic Microtiter Plate Reader (ELISA Analysis)
• Liquid Chromatograph/Mass Spectrometer (LC/MS)
• Liquid Chromatograph/Tandem Mass Spectrometer (LC/MS/MS)
• Online Solid-Phase Extraction
• Solvent Evaporator
• UV/Visible Spectrophotometer (Magnetic Particle ELISA)
• Walk-In Refrigeration

Goals of Methods Development

Methods development proceeds with three ideas in mind:

• To develop analytical methods for pesticides, pharmaceuticals, and the degradates of these compounds in soil and water that are important in water-quality studies.
• To automate methods so that samples may be analyzed for water-quality and environmental surveys quickly and inexpensively.
• To make methods simple and available for other offices of the USGS and researchers in universities.

Accomplishments of Methods Development

• Solid-phase extraction of water and soil samples for pesticides and antibiotics
• LC/MS analysis of pesticide compounds and their degradation products
• LC/MS/MS analysis of antibiotics compounds and their degradation products
• GC/MS analysis of pesticide compounds and their degradation products
• ELISA analysis of herbicides

Selected Methods Development References

1. Aga, D.S. and Thurman, E.M., 1993, Coupling Solid-Phase Extraction (SPE) and Enzyme-Linked Immunosorbent Assay (ELISA) for Ultratrace Analysis of Herbicides in Pristine Water: Analytical Chemistry, v. 65, p. 2894-2898.

2. Ferrer, I., Thurman, E.M., and Barcelo, D., 1997, Identification of Ionic Chloroacetanilide--Herbicide Metabolites in Surface Water and Ground Water by HPLC/MS Using Negative Ion Spray: Analytical Chemistry, v. 69, no. 22, p. 4547-4553.

3. Ferrer, Imma, Barcelo, Damia, Thurman, E.M., 2000, First LC/MS Determination of Cyanazine Amide, Cyanazine Acid, and Cyanazine in Groundwater Samples, Environmental Science and Technology, v. 34, no. 4, p. 714-718.

4. Ferrer, Imma, and Thurman, E.M., 2003, Liquid Chromatography/Mass Spectrometry, MS/MS and Time-of-Flight MS: Analysis of Emerging Contaminants., American Chemical Society Symposium 850, 415 p.

5. Lin, C.H., Lerch, R.N., Thurman, E.M., Garrett. H.E., George, M.F., 2002, Determination of Isoxaflutole (Balance) and its Metabolites in Water Using Solid Phase Extraction followed by High-Performance Liquid Chromatography with Ultraviolet or Mass Spectrometry: J. Agrie. Food Chem., v. 50, p.5816-5824.

6. Lindsey, M.E., Meyer, M.T., and Thurman, E.M., 2001, Analysis of Trace levels of Sulfonamide and Tetracycline Antimicrobials in Groundwater and Surface Water using Solid-Phase Extraction and Liquid Chromatography/Mass Spectrometry, Analytical Chemistry, v. 74, p. 4640-4646.

7. Meyer, M.T., Mills, M.S., and Thurman, E.M., 1993, Automated Solid-Phase Extraction of Herbicides from Water for Gas Chromatographic/Mass Spectrometric Analysis: Journal of Chromatography, v. 629, p. 55-59.

8. Mills, M.S. and Thurman, E.M., 1992, Mixed-Mode Isolation of Triazine Metabolites in Soil and Aquifer Sediments Using Automated Solid-Phase Extraction: Analytical Chemistry, v. 64, 1985-1990.

9. Thurman, E.M., Meyer, M.T., Pomes, M.L., Perry, C.A., and Schwab, A.P., 1990, Enzyme-Linked Immunosorbent Assay Compared With Gas Chromatography/Mass Spectrometry for the Determination of Triazine Herbicides in Water: Analytical Chemistry, v. 62, no.18, p. 2043-2048.

10. Thurman, E.M., Ferrer, Imma, and Barcelo, Damia, 2001, Choosing between Atmospheric Pressure Chemical Ionization and Electrospray Ionization Interfaces for the HPLC/MS Analysis of Pesticides, Analytical Chemistry, v. 73, p. 5441-5449

11. Thurman, E.M., Ferrer, Imma, Parry, Rick, 2002, Accurate mass analysis of ethane sulfonic acid degradates of acetochlor and alachlor using high-preformance liquid chromatography and time-of-flight mass spectrometry: J. Chromato. A, 957, p.3-9.