FLUOROMETRIC ASSAY FOR THE DETECTION OF METHANOL IN AQUATIC ENVIRONMENTS AND BACTERIAL CULTURES

The measurement of ambient methanol in seawater has typically relied on methods requiring a significant time and cost investment, such as liquid or gas chromatography in tandem with mass spectrometry. Methods using colorimetry and fluorescence spectroscopy use cheaper, more accessible instrumentation and reagents that make possible the automation of analysis of large batches of samples. Furthermore, an easily replicable analysis of culture samples, taken from multiple time points and under different growth conditions, can demonstrate where and how methanol is produced, taken up, and utilized over time. Our goal is to develop a fluorometric method for quantifying methanol at nanomolar concentrations typical of lake and seawater. We combined the enzymatic transformation of methanol into formaldehyde with the Hantzsch ester synthesis of the fluorophore 3,5-diacetyl-1,4-dihydrolutidine (DDL) from formaldehyde. We evaluated standard-to-reagent ratio, methods of standard preparation, optimal pH and salinity for enzymatic and organic transformations, and testing both fluorescence and absorbance spectroscopy. Because of the intermediate transformation, we were also able to use this method to quantify formaldehyde. The method is being used to measure methanol and formaldehyde in environmental and bacterial culture samples, elucidating methanol metabolism and drawdown.

Presentation Preference: Poster

Primary Presenter: Keshav Srivenkatesh, University of North Carolina at Chapel Hill (ksrivenkatesh@yahoo.com)

Authors:

Keshav Srivenkatesh, University of North Carolina at Chapel Hill  (ksrivenkatesh@unc.edu)

Samantha Cerda, University of North Carolina at Chapel Hill  (samanth@email.unc.edu)

Marc Alperin, University of North Carolina at Chapel Hill  (alperin@email.unc.edu)

Scott Gifford, University of North Carolina at Chapel Hill  (sgifford@email.unc.edu)