Rapid and sensitive detection of microcystin by immunosensor based on nuclear magnetic resonance

Wei Ma, Wei Chen, Ruirui Qiao, Chunyan Liu, Chunhui Yang, Zhuokun Li, Dinghua Xu, Chifang Peng, Zhengyu Jin, Chuanlai Xu, Shuifang Zhu, Libing Wang

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67 Citations (Scopus)


A stable and sensitive toxin residues immunosensor based on the relaxation of magnetic nanoparticles was developed. The method was performed in one reaction and offered sensitive, fast detection of target toxin residues in water. The target analyte, microcystin-LR (MC-LR) in Tai lake water, competed with the antigens on the surface of the magnetic nanoparticles and then influenced the formation of aggregates of the magnetic nanoparticles. Accordingly, the magnetic relaxation time of the magnetic nanoparticles was changed under the effect of the target analyte. The calibration curve was deduced at different concentrations of the target analyte. The limit of detection (LOD) of MC-LR was 0.6 ng g-1 and the detection range was 1-18 ng g-1. Another important feature of the developed method was the easy operation: only two steps were needed (1) to mix the magnetic nanoparticle solution with the sample solution and (2) read the results through the instrument. Therefore, the developed method may be a useful tool for toxin residues sensing and may find widespread applications.

Original languageEnglish
Pages (from-to)240-243
Number of pages4
JournalBiosensors and Bioelectronics
Issue number1
Publication statusPublished - 15 Sept 2009
Externally publishedYes


  • Detection
  • Immunosensor
  • Magnetic nanoparticles
  • Microcystin
  • Nuclear magnetic resonance
  • Sensitive

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