Single-Measurement Excitation/Emission Matrix Spectrofluorometer for Determination of Hydrocarbons in Ocean Water. 2. Calibration and Quantitation of Naphthalene and Styrene

An excitation/emission matrix imaging spectrofluorometer was employed for quantitation of two fluorescent compounds, naphthalene and styrene, contained in ocean water exposed to gasoline. Multidimensional parallel factor (PARAFAC) analysis models were used to resolve the naphthalene and styrene fluorescence spectra from a complex background signal and overlapping spectral interferents not included in the calibration set. Linearity was demonstrated over 2 orders of magnitude for determination of naphthalene with a detection limit of 8 parts per billion. Similarly, nearly 2 orders of magnitude of linearity was demonstrated in the determination of styrene with an 11 ppb limit of detection. Furthermore, the synthesis of the EEM spectrofluorometer and the PARAFAC analysis for unbiased prediction of naphthalene and styrene concentration in mixture samples containing uncalibrated spectral interferents was demonstrated.