Based on window function optimization and DFT verification to establish terahertz fingerprint of triphenyl phosphate for non-destructive analysis.

Triphenyl phosphate (TPHP), an emerging pollutant with neurotoxic and reproductive toxicity, severely threatens global food safety and human health through environmental exposure risks and bioaccumulation. A rapid and non-destructive detection method for TPHP was established using terahertz time-domain spectroscopy (THz-TDS). This study systematically analyzed the impact of window functions on TPHP fingerprint spectra and integrated DFT calculations, chemometric analysis, and baseline correction algorithms for TPHP quantitation and qualitation in real samples. Boxcar window optimally retained absorption peaks of TPHP at 0.94, 1.21, 1.45, and 1.70 THz. B3LYP-D3/6-31G(d,2p) basis set effectively corrected the frequency shift caused by weak intermolecular interactions, resulting in a high degree of agreement between the theoretical and experimental spectra in 0.1-2.0 THz range. AirPLS algorithm effectively eliminated matrix interference in real samples, enabling accurate analysis of TPHP with a LOD of 0.09%, which advanced the practical application of THz-TDS in food safety and environmental monitoring.