Development of SPE/HPLC-DAD to determine residues of selected disinfectant agents in surface water

The aim of our research was to develop a chromatographic method for simultaneous determination of five substances used as disinfectant agents. Biphenyl-2-ol (BPh), chloramine T (ChT), 4-chloro-3-methylphenol (4C3MPh), triclosan (TCS), and triclocarban (TCC) were determined using high-performance liquid chromatography. Chromatographic analyses were carried out on a Develosil RP Aqueous AR-5 RP-30 column (250 mm × 4.6 mm, 5.0 μm particles) with gradient elution of mobile phase including methanol and water, and with a DAD detector. Satisfactory resolution of the determined substances was obtained in 10 minutes. The linearity ranges of the calibration curves (in matrix) of examined disinfectants ranged from 0.10 to 10.00 μg·mL⁻¹ for ChT, 4C3MPh and TCC, and from 0.25 to 10.00 μg·mL⁻¹ for BPh and TCS. The developed method was applied to determine of mentioned compounds in water samples. Water samples were prepared for chromatography analyses by using C18 solid phase extraction discs. The recoveries of analyzed substances ranged from 82 to 101% (except for Chloramine T, which is unstable in water medium). Analyses were operated after extraction of analytes from 3 L of real water samples. The method detection limits in samples of water were: 1.6 ng·mL⁻¹ for BPh, 0.6 ng·mL⁻¹ for ChT, 1.4 ng·mL⁻¹ for 4C3MPh, 1.9 ng·mL⁻¹ for TCS, and 1.0 ng·mL⁻¹ for TCC. This method was successfully applied to analyze examined disinfectants in surface water samples collected from rivers and wastewater in Poland. Four of five compounds were detected in the tested samples in the concentration ranging from 5.05 to 30.36 μg·L⁻¹.