Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analys...Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analysis.In this work,a magnetic metal-organic framework Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]was synthesized and applied as a dispersive micro-solid phase extraction adsorbent for TCs enrichment.Effects of dispersive micro-solid phase extraction conditions including extraction time,solution p H,and elution solvent on the extraction efficiencies of TCs were investigated.Results show that TCs could be enriched efficiently by Fe_(3)O_(4)@[Cu_(3)(btc)_(2)],and electrostatic interaction between TCs and Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]dominated this process.Combined with liquid chromatography-tandem mass spectrometry,four TCs residues (oxytetracycline,tetracycline,chlortetracycline,and doxycycline) in natural waters were determined.The detection limits (LOD,S/N=3) of the four antibiotics were 0.01-0.02μg/L,and the limits of quantitation (LOQ,S/N=10)were 0.04-0.07μg/L.The recoveries obtained from river water and aquaculture water spiked with three TCs concentration levels ranged from 70.3%to 96.5%with relative standard deviations of 3.8%-12.8%.Results indicate that the magnetic metal-organic framework based dispersive micro-solid phase extraction is simple,rapid and high-loading for antibiotics enrichment from water,which further expand the practical application of metal-organic frameworks in sample pretreatment for environmental pollutant analysis.展开更多
2,4,6-trichlorophenol molecularly imprinted suspension polymer has been prepared and applied to the molecularly imprinted micro-solid-phase extraction procedure for selective preconcentration of phenolic compounds fro...2,4,6-trichlorophenol molecularly imprinted suspension polymer has been prepared and applied to the molecularly imprinted micro-solid-phase extraction procedure for selective preconcentration of phenolic compounds from environmental water samples. The influence of functional monomer, cross-linker, polymerization condition, porogen, and the ratio of template molecule and functional monomer to cross-linker on the size of the obtained particles were investigated. It was found that methyacrylic acid as functional monomer, divinylbenzene as cross-linker, the molar ratio of template molecule and functional monomer to cross-linker was 1:4:20, the amount of AIBN was 100 mg, ultraviolet radiation at 365 nm were the optimal conditions, and at these conditions, the polymers had the best adsorption efficiency and had the monodispersity of 2 - 3 μm microsphere particles. The characteristics of the MIMSPE method were valid by high performance liquid chromatography. This MIMSPE-HPLC method has been successfully applied to the direct preconcentration and determination of phenolic compounds (phenol, 4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, pentachlorophenol) in environmental water samples.展开更多
In the present study,a method was described for the extraction of Sunset Yellow(SY)and Tartrazine(TZ)as anionic food dyes in actual samples by using magnetic calcined layered double hydroxide onto gra-phene oxide(MgFe...In the present study,a method was described for the extraction of Sunset Yellow(SY)and Tartrazine(TZ)as anionic food dyes in actual samples by using magnetic calcined layered double hydroxide onto gra-phene oxide(MgFe CLDH)/GO(called MgO/MgFe_(2)O_(4)/GO)sorbent.The analytes were accumulated on MgO/MgFe_(2)O_(4)/GO-NCs with more detail recognized by XRD,FESEM,EDS element mapping,VSM and FTIR methods.The prepared nanocomposite(NC)was employed as an extractive phase for dispersive micro-solid phase extraction(D-m-SPE)of SY and TA from actual samples.Then,the extracted SY and TZ dyes were analyzed by UVevis spectrophotometer.Main variables related to the extraction process including pH,nano composite mass,sonication and vortex time and eluent volume were optimized by central composite design(CCD).The optimum conditions obtained for pH,nano composite mass,soni-cation and vortex time and eluent volume were 6.0,0.02 g,16 s and 6.40 min,and 500 mL,respectively.The extraction recovery equal to 96.31%and 97.66%for SY and TZ,respectively obtained from the predicted model,was in agreement with the experimental data(95.32±2.33%and 96.89±1.84%).In addition,under the optimal conditions,the calibration curve was found out to be linear over the con-centration range of 0.5e2.50 mg L^(-1)with R^(2)>0.98.The LODs ranged from 0.14 to 0.16 mgL^(-1).Furthermore,the enrichment factors(EF)were achieved in the range of 20.65e36.66 with pre-concentration factor(PF)of 20.In the meantime,the obtained assay accuracy in the analysis of medi-cal extract of Miranda Drink,Saffron and water samples fell within the range of 93.00%-107.00%,whilst the precision expressed RSD lower than 3.50%.展开更多
基金supported by the National Natural Science Foundation of China(No.21607003).
文摘Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analysis.In this work,a magnetic metal-organic framework Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]was synthesized and applied as a dispersive micro-solid phase extraction adsorbent for TCs enrichment.Effects of dispersive micro-solid phase extraction conditions including extraction time,solution p H,and elution solvent on the extraction efficiencies of TCs were investigated.Results show that TCs could be enriched efficiently by Fe_(3)O_(4)@[Cu_(3)(btc)_(2)],and electrostatic interaction between TCs and Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]dominated this process.Combined with liquid chromatography-tandem mass spectrometry,four TCs residues (oxytetracycline,tetracycline,chlortetracycline,and doxycycline) in natural waters were determined.The detection limits (LOD,S/N=3) of the four antibiotics were 0.01-0.02μg/L,and the limits of quantitation (LOQ,S/N=10)were 0.04-0.07μg/L.The recoveries obtained from river water and aquaculture water spiked with three TCs concentration levels ranged from 70.3%to 96.5%with relative standard deviations of 3.8%-12.8%.Results indicate that the magnetic metal-organic framework based dispersive micro-solid phase extraction is simple,rapid and high-loading for antibiotics enrichment from water,which further expand the practical application of metal-organic frameworks in sample pretreatment for environmental pollutant analysis.
文摘2,4,6-trichlorophenol molecularly imprinted suspension polymer has been prepared and applied to the molecularly imprinted micro-solid-phase extraction procedure for selective preconcentration of phenolic compounds from environmental water samples. The influence of functional monomer, cross-linker, polymerization condition, porogen, and the ratio of template molecule and functional monomer to cross-linker on the size of the obtained particles were investigated. It was found that methyacrylic acid as functional monomer, divinylbenzene as cross-linker, the molar ratio of template molecule and functional monomer to cross-linker was 1:4:20, the amount of AIBN was 100 mg, ultraviolet radiation at 365 nm were the optimal conditions, and at these conditions, the polymers had the best adsorption efficiency and had the monodispersity of 2 - 3 μm microsphere particles. The characteristics of the MIMSPE method were valid by high performance liquid chromatography. This MIMSPE-HPLC method has been successfully applied to the direct preconcentration and determination of phenolic compounds (phenol, 4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, pentachlorophenol) in environmental water samples.
文摘In the present study,a method was described for the extraction of Sunset Yellow(SY)and Tartrazine(TZ)as anionic food dyes in actual samples by using magnetic calcined layered double hydroxide onto gra-phene oxide(MgFe CLDH)/GO(called MgO/MgFe_(2)O_(4)/GO)sorbent.The analytes were accumulated on MgO/MgFe_(2)O_(4)/GO-NCs with more detail recognized by XRD,FESEM,EDS element mapping,VSM and FTIR methods.The prepared nanocomposite(NC)was employed as an extractive phase for dispersive micro-solid phase extraction(D-m-SPE)of SY and TA from actual samples.Then,the extracted SY and TZ dyes were analyzed by UVevis spectrophotometer.Main variables related to the extraction process including pH,nano composite mass,sonication and vortex time and eluent volume were optimized by central composite design(CCD).The optimum conditions obtained for pH,nano composite mass,soni-cation and vortex time and eluent volume were 6.0,0.02 g,16 s and 6.40 min,and 500 mL,respectively.The extraction recovery equal to 96.31%and 97.66%for SY and TZ,respectively obtained from the predicted model,was in agreement with the experimental data(95.32±2.33%and 96.89±1.84%).In addition,under the optimal conditions,the calibration curve was found out to be linear over the con-centration range of 0.5e2.50 mg L^(-1)with R^(2)>0.98.The LODs ranged from 0.14 to 0.16 mgL^(-1).Furthermore,the enrichment factors(EF)were achieved in the range of 20.65e36.66 with pre-concentration factor(PF)of 20.In the meantime,the obtained assay accuracy in the analysis of medi-cal extract of Miranda Drink,Saffron and water samples fell within the range of 93.00%-107.00%,whilst the precision expressed RSD lower than 3.50%.
