Enhancing Fluorescence Detection Accuracy for Aromatic Pollutants in Aquatic Environments via Absorption Spectroscopy-Based Inner Filter Effect Compensation

To address the quantitative distortion problem caused by the primary internal filtration effect (PIFE) resulting from coexisting substances in the fluorescence detection of aromatic pollutants, this study proposes a multi-component concentration quantification correction model that integrates transmittance absorbance and lateral (90°) fluorescence intensity. Using styrene as the target analyte and anthracene/phenanthrene as representative interferents, by establishing a coupled framework of excitation light decay dynamics and fluorescence emission, the nonlinear PIFE problem was transformed into a linear regression task. The experimental results show that: under the coexistence of anthracene and phenanthrene, the model reduces the detection deviation of styrene from 40 to 63% to within 10%, and the correction accuracy of the three-component mixed system is increased by 3–5 times. This work provides a theoretical framework for fluorescence quantitative analysis in complex systems, and also offers a new method for high-precision online monitoring of aromatic organic pollutants.