A new strategy for pentachlorophenol monitoring in water samples using ultra-high performance liquid chromatography - mass spectrometry tandem
Résumé
A novel sensitive and rapid anal. approach based on ultra-high performance liq. chromatog. - mass spectrometry (UHPLC/MS/MS) tandem was developed for the monitoring of pentachlorophenol in water samples. Chromatog. sepn. was carried out on Acquity BEH C18 (100 × 2.1 mm, 1.7 μm) column under gradient mode using a mobile phase consisting of acetonitrile/ultrapure water/formic acid. Quantification of pentachlorophenol was performed on a triple-quadrupole tandem mass spectrometer under multiple reaction monitoring (MRM) mode, via a neg. electrospray ionization (ESI-). The limit of quantification of the developed instrumental method was 0.3 μg L-1. The linearity was validated within the concn. range 0.1-100 μg L-1 with a correlation coeff. (R2) of 0.998. Intra-day and inter-day precision values were 99.78 and 99.12%, resp. Moreover, for the application to real water samples, a solid phase extn. method (SPE) was proposed for the extn. and preconcn. of analyte. Some of the main factors involved in the SPE extn. process such solid phase material, elution solvent and sample vol. were investigated and optimized in order to maximize the extn. efficiencies. Oasis HLB cartridges showed the best results in term of extn. recovery. High analyte recoveries (between 98.2% and 100.18%) were achieved with the proposed SPE procedure and the extn. RSD was less than 3.1%. In addn., the whole new anal. strategy (SPE-UHPLC/MS/MS) was then successfully applied for pentachlorophenol quantification in natural waters at low part per trillion levels.