基于掺杂金属有机骨架CeDUT-52分散固相萃取/高效液相色谱法检测水中的双酚类化合物

Detection of Bisphenols Compounds in Water by High Performance Liquid Chromatography with Dispersive Solid Phase Extraction Based on Ce-Doped DUT-52 Metal Organic Framework

利用溶剂热法构筑了CeDUT-52吸附剂,将其用于水中双酚A(BPA)、双酚F(BPF)和双酚AF(BPAF)3种双酚类化合物的分散固相萃取(DSPE),并结合高效液相色谱-紫外检测,建立了水中3种双酚类化合物的分析方法。采用X射线衍射仪(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)和X射线能谱仪(EDS)对构筑的CeDUT-52吸附剂进行表征,结果显示金属Ce成功掺杂于八面体结构的DUT-52中,掺杂后的吸附剂粒径变小。实验考察了吸附剂用量、吸附时间、洗脱溶剂种类以及洗脱体积对水中3种双酚类化合物萃取效率的影响。结果显示,40 mg吸附剂在20 min内即可实现对目标物的完全吸附。采用最优DSPE条件,BPA和BPF在0.3~300μg/L范围内,BPAF在0.6~600μg/L范围内线性关系良好(r≥0.999 8),检出限和定量下限分别为0.1~0.2μg/L和0.3~0.6μg/L,在1、5、10μg/L 3个加标水平下的回收率为82.5%~101%,相对标准偏差(RSD)不大于10%,富集因子为92~102。该方法快速、灵敏,能够满足水中双酚类化合物的分析要求。

Bisphenols(BPs)may dissolve from pipeline or other plastic products and pollute water.It is very important to analyze the BPs in water rapidly and accurately,though the matrix of the water sample is complex and the target analytes are usually at trace level.Therefore,how to enrich and separate the target objects efficiently is the key point for the determination of BPs.In this paper,a Ce(Ⅲ)doped metal organic framework composite(Ce DUT-52)was synthesized via a solvothermal method,and used as an effective adsorbent for dispersive solid phase extraction(DSPE)to enrich three BPs in water,including bisphenol A(BPA),bisphenol F(BPF)and bisphenol AF(BPAF).The structure and morphology of the Ce DUT-52 was characterized by X-ray diffractometry(XRD),Fourier-transform infrared spectroscopy(FT-IR), scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS).The XRD,FT-IR and EDS results revealed that Ce was successfully doped into the octahedral DUT-52.Meanwhile,it was found in the SEM that the particle size of the doped adsorbent decreased from 2 μm to 500 nm.To acquire the optimal extraction conditions,effects of the Ce DUT-52 usage(10,20,30,40 and 50 mg),adsorption time(5,10,15,20 and 25 min),elution solvent(methanol,acetonitrile,acetone and isopropanol)and elution volume(0. 5 m L × 1,0. 5 m L × 2,0. 5 m L × 3 and 0. 5 m L × 4)were investigated for the three BPs in water.Results showed that BPs could be completely adsorbed with 40 mg of adsorbent in 50 m L water within 20 minutes.Elution efficiency could reach88. 9%-101%with 0. 5 m L × 3 of methanol.Under the optimal conditions,a simple and sensitive method for the detection of three BPs was established by high performance liquid chromatography-ultraviolet detection(HPLC-UV)with the Ce DUT-52 based DSPE. The limits of detection(LOD), limits of quantitation(LOQ), accuracy and precision of the method were evaluated. The developed method showed a good linear relationship in the range of 0. 3-300 μg/L for BPA and BPF,0. 6-600 μg/L for BPAF with correlation coefficients(r)not less than 0. 999 8.The LODs and LOQs were in the range of0. 1-0. 2 μg/L and 0. 3-0. 6 μg/L,respectively.The recoveries for BPs in water samples at 3 spiked levels of 1,5 and 10 μg/L ranged from 82. 5%to 101%,with relative standard deviations(RSD)not more than 10%.The enrichment factors of the method were between 92 and 102.The proposed method was suitable for the rapid and sensitive determination of BPs in water samples.