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Oxytetracycline at Environmental Interfaces Studied by Second Harmonic Generation

Oxytetracycline at Environmental Interfaces Studied by Second Harmonic Generation. Patrick L. Hayes and Franz M. Geiger Department of Chemistry, Northwestern University, Evanston IL WMRC Symposium on PPCPs in the Illinois Environment -- April 25, 2008. Oxytetracycline.

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Oxytetracycline at Environmental Interfaces Studied by Second Harmonic Generation

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  1. Oxytetracycline at Environmental Interfaces Studied by Second Harmonic Generation Patrick L. Hayes and Franz M. Geiger Department of Chemistry, Northwestern University, Evanston IL WMRC Symposium on PPCPs in the Illinois Environment -- April 25, 2008

  2. Oxytetracycline Oxytetracycline (OTC) Mifflin et al. J. Phys. Chem. B 2006, 110, 22577. Hayes et al. J. Phys. Chem. C 2007, 111, 8796. Morantel Konek et al. J. Am. Chem. Soc. 2005,127, 15771.

  3. Oxytetracycline Oxytetracycline (OTC) • Tetracyclines are used in humans and cattle/poultry/swine • Estimated 3 million pounds of tetracyclines used annually for growth stimulation in livestock! • 25-75% of tetracyclines administered to animals are excreted in the active form. Hileman, B. “Resistance is on the Rise” Chem. Eng. News 2001,February 19, 47. Kulshrestha, P.; Giese, R. F. Aga, D.S. Environ. Sci. Technol. 2004, 38, 4097. Boxall, A. B. A. EMBO Reports 2004,5, 1110. Simon, N. S. Environ. Sci. Technol. 2005,39, 3480.

  4. Importance of Mobility: Case I “A Sticky Antibiotic” Bacterium Bacterium Bacterium Resistant Sticky Antibiotic SoilParticle SoilParticle SoilParticle SoilParticle Antibiotic Resistance in Soil Bacteria Localized

  5. Resistant Resistant Resistant Resistant SoilParticle SoilParticle SoilParticle SoilParticle Antibiotic Resistance in Soil Bacteria Importance of Mobility: Case II “A Mobile Antibiotic” Mobile Antibiotic Koike et al. Appl. Envir. Microbiol. 2007, 73, 4813.

  6. Challenges: • Complexity • Separating Bulk from Surface • Sensitivity Soils Pollutant Plume Water Table Second Harmonic Generation Surface Waters Environmental Interfaces Control Transport,Reactivity, Bioavailability

  7. Water Second Harmonic Generation (SHG) Aqueous UV-Vis Spectrum Fundamental Laser Light Nitrate Surface Spectrum Quartz Fused Quartz/Water Surface Spectrum Second Harmonic Generation (SHG) • Advantages: • Surface-Specific • Sensitivity Allows for Real-time • Monitoring of Adsorption • Experiments Run Under Flow Conditions “Measurable” is ESHG  Nads Eisenthal, K. B. Chem. Rev. 1996, 96, 1343. Shen, Y. R. “The Principles of Nonlinear Optics” John Wiley & Sons: New York, 2003.

  8. I I time time SiO2 laser PMT Aqueous Phase Waste Teflon Flow Cell Analyte Water UV-Vis Experimental Setup Pulsed & Tunable Laser Mifflin, A.L.; Gerth, K.A.; Weiss, B.M. Geiger, F.M. J. Phys. Chem. A 2003, 107, 6212. Mifflin, A.L.; Gerth, K.A.; Geiger, F.M. J. Phys. Chem. A2003, 107, 9620. Mifflin, A.L.; Musorrafiti, M.J.; Konek, C.T.; Geiger, F.M. J. Phys. Chem.B2005,109, 24386. Hayes et al. J. Phys. Chem. C 2007, 111, 8796.

  9. Model Environmental Interfaces Fused Quartz Pollutant Common Organic Motifs Organic Adlayer SoilParticle Increasing Complexity Our Strategy: Use synthetic chemistry to: Isolate and study individual functional groups. Build more complex model interfaces. Sutton, R.; Sposito, G. Environ. Sci. Technol. 2005, 39, 9009. Al-Abadleh et al. J. Am. Chem. Soc. 2004,126, 11126. Gibbs-Davis, J.M.; Hayes, P.L.; Scheidt K. A.; Geiger F.M. J. Am. Chem. Soc. 2007, 129, 7175. Hayes et al. J. Phys. Chem. C 2007, 111, 8796.

  10. OTC Spectroscopy and Adsorption/Desorption TraceatFused Quartz/Water Interface(pH 8) OTC UV-Vis SHG OTC Fused Quartz/Water OTC 5 x 10–5 M H2O H2O Mifflin et al. J. Phys. Chem. B 2006, 110, 22577.

  11. R =1+(r/n).Kd C/Co Pollutant Water x 0 OTC Isotherm & The Kd Model (pH 8) Retardation Factor: Kd = 0.11 mL/g Taking: (/n) = 4 – 10 g/cm3 Rf = 1.44 - 2.1 Rf = 2, corresponds to 50% reduction in OTC mobility relative to water. Langmuir, D. Aqueous Environmental Geochemistry; Prentice Hall,Inc: New Jersey, 1997. Hayes et al. J. Phys. Chem. C 2007, 111, 8796. Mifflin et al. J. Phys. Chem. B 2006, 110, 22577.

  12. Summary of Isotherm Experiments: Mobility Mifflin et al. J. Phys. Chem. B 2006, 110, 22577. Hayes et al. J. Phys. Chem. C 2007, 111, 8796.

  13. Predicting OTC Mobility: Surface Energy and OTC Retardation For Hydrogen-Bonding Surfaces, and Taking: (/n) = 4 -10 g/cm3 (c)  = 49º, 9 mJ/m2 f e (f) c  = 75º, 22 mJ/m2 d a b (a) (b) (c) (d) (e) (f) Mifflin et al. J. Phys. Chem. B 2006, 110, 22577. Hayes et al. J. Phys. Chem. C 2007, 111, 8796.

  14. Predicting OTC Mobility: Surface Energy and OTC Retardation For Hydrogen-Bonding Surfaces, and Taking: (/n) = 4 -10 g/cm3 IHSS Humic Acid: f Contact Angle: 59(3) Surface Energy: 14(1) mJ/m2 Predicted Rf: 1.4(1) e c IHSS HA Aldrich Humic Acid: d Aldrich HA Contact Angle: 57(3) Surface Energy: 13(1) mJ/m2 Predicted Rf: 1.3(1) a b (a) (b) (c) (d) (e) (f) Mifflin et al. J. Phys. Chem. B 2006, 110, 22577. Hayes et al. J. Phys. Chem. C 2007, 111, 8796.

  15. f e c d a b Mobile OTC ??? Connections to Mobility • OTC will tend to be less mobile in silica-rich soils that: • Contain natural organic matter with a large density of benzoic acid functional groups • Display high interfacial energy

  16. Geiger Group 2006 Acknowledgements • Professor Franz M. Geiger • Dr. Amanda Mifflin (OTC) • Dr. Julianne Gibbs-Davis • Professor Karl A. Scheidt Funding:

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