Trace identification of sulfate anion in bottled and metropolitan water samples collected from various provinces of Saudi Arabia

Water quality especially drinking water is highly significant to human lives. To access the safe and secure drinking water, nowadays it has become an issue of global concerns. A novel method using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was proposed to analyze sulfate level in bottled and metropolitan water collected from various provinces of Saudi Arabia. The chromatographic analysis was achieved within 1 min with reversed phase Waters Acquity® BEH C18 column and a triple quadrupole mass spectrometer. The performance of the optimized system was established, attaining linearity (r2 >0.999) over a wide-ranging concentration from several below hundred mg/L to the detection limit of sulfate. In terms of relative standard deviation of the samples (RSD%), the excellent run-to-run (<2%, n = 5) and day-to-day (<4%, n = 5) precisions were achieved when examining a sulfate standard (0.01 mg/L) and non-spiked bottled water sample with the concentration of sulfate (4.76mg/L). The developed method is helpful to identify sulfate in bottled and metropolitan water samples. Sulfate content in the bottled water ranged between 3.31 to 76.22 mg/L, while higher level was determined (36.78 to 268.42 mg/L) in metropolitan water samples. The excellent quality parameters and insignificant matrix effects achieved during analysis have made favorable to analyze sulfate in water samples, and offered advantages over conventional techniques and rigorous sample preparation procedures.