A high efficient adsorbent for plant growth regulators based on ionic liquid and β-cyclodextrin functionalized magnetic graphene oxide

Talanta. 2019 Mar 1:194:14-25. doi: 10.1016/j.talanta.2018.10.013. Epub 2018 Oct 11.


Four types of ionic liquids which composed of cation with imidazole ring and anion with benzene, naphthalene, anthraquinone and naphthoquinone ring were prepared and named VOIm+BenSO3-, VOIm+NapSO3-, VOIm+AQSO3- and VOIm+NQSO3-, respectively. Then, ionic liquids and β-cyclodextrin functionalized magnetic graphene oxide materials were firstly synthesized for the extraction of 23 plant growth regulators in vegetable samples. The synthesized materials anticipated the unique properties of ionic liquids, β-cyclodextrin, graphene oxide and Fe3O4@SiO2, including high surface area, high supramolecular recognition capability, superparamagnetism and large delocalized π-electron system, which were successfully characterized. Among four kinds of ionic liquids functionalized adsorbents, the VOIm+AQSO3- modified material exhibited high adsorption capability to 7 plant growth regulators compared with Fe3O4@SiO2/GO/β-CD, Fe3O4@SiO2/GO and other three types of ionic liquids based adsorbents. Parameters that could affect the recoveries of 7 plant growth regulators were investigated, such as mass ratio of Fe3O4@SiO2/GO/β-CD to ionic liquids, salt concentration, pH, amount of adsorbent, extraction time and desorption solvent. Under the optimal condition, the magnetic solid phase extraction method using VOIm+AQSO3- and β-cyclodextrin functionalized magnetic graphene oxide material (Fe3O4@SiO2/GO/β-CD/IL) as adsorbent was developed and coupled with ultra-high performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry for the determination of 7 plant growth regulators in vegetable samples. Validation results showed that the limit of detection and limit of quantitation were in the range of 0.01-0.18 μg/kg and 0.03-0.58 μg/kg, respectively. The satisfactory linearities were acquired in the concentration of 2-50 μg/kg with the correlation coefficients higher than 0.9982. Taken together, the synthesized Fe3O4@SiO2/GO/β-CD/IL was a highly effective magnetic solid phase extraction adsorbent for the enrichment of trace level of plant growth regulators in vegetable samples.

Keywords: Graphene oxide; Ionic liquid; Magnetic solid phase extraction; Plant growth regulators; β-cyclodextrin.

MeSH terms

  • Adsorption
  • Graphite / chemistry*
  • Hydrogen-Ion Concentration
  • Ionic Liquids / chemistry*
  • Limit of Detection
  • Magnetite Nanoparticles / chemistry
  • Models, Molecular
  • Molecular Conformation
  • Oxides / chemistry*
  • Plant Growth Regulators / analysis
  • Plant Growth Regulators / chemistry*
  • Plant Growth Regulators / isolation & purification*
  • Silicon Dioxide / chemistry
  • Solid Phase Extraction
  • Solvents / chemistry
  • Time Factors
  • Vegetables / chemistry
  • beta-Cyclodextrins / chemistry*


  • Ionic Liquids
  • Magnetite Nanoparticles
  • Oxides
  • Plant Growth Regulators
  • Solvents
  • beta-Cyclodextrins
  • Silicon Dioxide
  • Graphite