TiO2-coated Hollow Fiber Micro-Extraction Combined with Electrothermal Vaporization-Inductively Coupled Plasma Mass Spectrometry for Trace Elements Analysis in Environmental Water Samples / 分析化学

ABSTRACT

TiO2 coated hollow fiber ( HF) was prepared by sol-gel method and characterized by X-ray powder diffraction and scanning electron microscope. The adsorption performances of the self-prepared TiO2 coated HF for interest metal ions were explored. The sample solution was extracted for 30 min at pH 8. 0 under stirring at speed of 700 r/min, then desorpted with 100μL of 1 mol/L HNO3 . On the basis of this, a method combining TiO2 coated HF micro-solid phase extraction with electrothermal vaporization-inductively coupled plasma mass spectrometry ( ICP-MS ) was developed for the determination of trace metal ions in environmental water samples. Under the optimized conditions, the limits of detection obtained by the proposed method were 0. 039, 0 . 021 , 0 . 009 and 0 . 018 ng/mL for CrⅢ, CuⅡ, CdⅡ and PbⅡ with enrichment factors of 12 . 5 , 11 . 7 , 10. 3 and 18. 6, respectively. The preparation reproducibility of self-prepared TiO2 coated HF ranged from 4. 5% to 6. 8% (n=9) in one batch, and from 7. 7% to 9. 6% (n=7) in batch-to-batch. The developed method has been validated by analyzing a certified reference material ( GSBZ50009-88 200925 ) and also applied to the analysis of CrⅢ, CuⅡ, CdⅡ and PbⅡ in East Lake water and snow water successfully. Meanwhile, TiO2 coated HF stir bar was prepared for a comparison and it was demonstrated that TiO2 coated HF displayed higher extraction efficiency and adsorption capacity for target ions.