Evaluation of three-way fluorescence data-based for simultaneous determination of polycyclic aromatic hydrocarbons in tea infusion samples at sub-ppb levels by second-order multivariate calibration

In this work, two fast and low solvent-consumption analytical methods were evaluated for the determination of the eight polycyclic aromatic hydrocarbons (PAHs), commonly named PAH8, in tea infusion samples by second-order multivariate calibration. The analytical performance of the excitation-emission matrix fluorescence (EEMF) and retention time-emission spectra matrices (RTEFM) data was compared, and these methods were applied to the analysis of real samples. Better figures of merit were obtained with EEMF (detection limit: 0.05–0.22 μg L⁻¹; analytical sensitivity: 14.8–68.9) than with those of RTEFM (detection limit: 1.5–12.1 μg L⁻¹; analytical sensitivity: 0.4–4.9). However, in the analysis of tea infusion samples, the method based on RTEFM showed a lower prediction error (4.0–9.7%) and better accuracy than did the reference method. Finally, the proposed methods were applied to real tea infusions obtained from green and black tea samples containing PAHs at ng L⁻¹ levels, including a preconcentration step on a C-18 SPE cartridge, demonstrating the analytical potential of these methods.