Multi-wavelength fluorescence detection of fecal contamination in complex matrices and fluorescence characterization of petroleum contamination in coastal marine waters

Date of Completion

January 2000


Chemistry, Analytical|Biophysics, General




The use of fluorometric methodologies for the detection of molecular chemical compounds continues to play a significant role in many fields of environmental chemistry and microbiology. Fluorescence methodologies have been and are used extensively in biochemical assays and petroleum oil fingerprinting/profiling. Fluorometric assays for detecting enzymes endogenous to fecal coliforms in drinking and recreational bathing waters have been used as a general screening indicator for pathogenic organisms since the early nineteen eighties. In addition, fluorescence fingerprinting/profiling of petroleum oils from the subsurface water column to identify a source responsible for an oil spill have been used since the early nineteen seventies. Both of these fluorescence applications have proven to be invaluable for providing important diagnostic information as to the degree of marine pollution. However, present methods used for detecting bacterial pollution are still plagued with problems originating from sample composition, matrix interference and fluctuations in various instrumental components such as lamps and detectors over the time of the assay. The fluorescence methods used for identifying oil-spill sources have also been plagued with variability and a degree of uncertainty. Research included in this Dissertation addresses certain aspects and enumerates how certain of those problems have been and can be overcome. The fluorescent ratio method developed in this research has shown to significantly improve the accuracy and sensitivity of detecting fecal pollution in marine waters via substrate to enzyme assays. In addition, the enumeration of the important wavelengths has demonstrated the potential of an online probe detector to distinguish different oils from one another in a subsurface water column using a flashing xenon light source and five different emission bandpass filters. A new generation of in-situ, on-line oil contamination detector is being developed upon the design of an established commercial oil detector provided by the Spectrogram. Corporation, North Haven, CT. ^