Sanz Rodriguez Estrella, Lam Shing, Smith Gregory G, Haddad Paul R, Paull Brett
Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Sandy Bay, Hobart, Tasmania, 7001, Australia.
Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, Private Bag 49, Hobart, Tasmania, 7001, Australia.
Heliyon. 2021 Apr 27;7(4):e06885. doi: 10.1016/j.heliyon.2021.e06885. eCollection 2021 Apr.
A direct, robust, accurate and highly sensitive method for oxyhalide species in natural waters, including seawater, using suppressed ion chromatography coupled with mass spectrometry (IC-MS) is described. The method utilised a high capacity, high efficiency anion-exchange column (Dionex IonPac AS11-HC, 4 mm, 2 × 250 mm), with the separation achieved using an electrolytically generated potassium hydroxide gradient, delivered at 0.380 mL min. Applying the method, detection limits for iodate, bromate, and chlorate in seawater after direct sample injection (20 μL injection volume, samples diluted 10-fold), were 11, 30 and 13 ng L (ppt), respectively. Standard addition calibrations to ozonated seawater samples were linear, in all cases R > 0.999 ( = 10), with intra-day repeatability of 3.7, 11.2 and 1.8 % RSD ( = 10) for a low-level standard mixture (0.30 μg L of iodate, 0.15 μg L of bromate, and 1.50 μg L of chlorate). The method was applied to the analysis of seawater samples taken pre- and post-disinfection points within a recirculating aquacultural system. Iodate, bromate and chlorate were detected as the main oxyanionic disinfection by-products, demonstrating the practical utility of the new method as a valuable tool for monitoring changes to seawater composition following disinfection treatments.
本文描述了一种使用抑制型离子色谱-质谱联用（IC-MS）直接、稳健、准确且高灵敏度地测定天然水体（包括海水）中卤氧化物的方法。该方法采用高容量、高效率的阴离子交换柱（戴安IonPac AS11-HC，4 mm，2×250 mm），通过电解产生的氢氧化钾梯度进行分离，流速为0.380 mL/min。应用该方法，直接进样（进样体积20 μL，样品稀释10倍）后，海水中碘酸盐、溴酸盐和氯酸盐的检测限分别为11、30和13 ng/L（ppt）。对臭氧氧化后的海水样品进行标准加入校准呈线性，在所有情况下R>0.999（n = 10），对于低水平标准混合物（0.30 μg/L碘酸盐、0.15 μg/L溴酸盐和1.50 μg/L氯酸盐），日内重复性的相对标准偏差（RSD）分别为3.7%、11.2%和1.8%（n = 10）。该方法应用于循环水养殖系统中消毒前后海水样品的分析。碘酸盐、溴酸盐和氯酸盐被检测为主要的含氧阴离子消毒副产物，证明了该新方法作为监测消毒处理后海水成分变化的有价值工具的实际效用。
