Preparation of poly(ε-lysine)-cyclodextrin coated Fe3O4 nanoparticles for selective separation of natural medicine: Scutellarin

In the present study, poly(ε-lysine)-cyclodextrin coated Fe 3 O 4 nanoparticles (PL-CD@Fe 3 O 4 ) were prepared by co-precipitation method. Then the PL-CD@Fe 3 O 4 nanoparticles were studied of the characterization and the selective separation performance for natural medicine (scutellarin). The experimental results showed that PL-CD@Fe 3 O 4 nanoparticles were successfully prepared with a particle size of about 30 nm and a saturation magnetization of 40 emu/g. When the nanoparticles were in the environment of pH = 7, the stability was the best, the adsorption capacity was the strongest, and the number of recyclable times was the most. Langmuir model deduced that the maximum adsorption capacity of the nanoparticles was 76.3 mg/g. In addition, the experimental results of using nanoparticles to separate SCU in the crude extract showed that the purity of SCU could be increased from 72.2% to 93.5% after repeated cyclic separation three times. Two dimensional NMR analysis showed that the selective separation of SCU by PL-CD@Fe 3 O 4 was mainly caused by the host–guest interaction between cyclodextrin and SCU. In conclusion, the PL-CD@Fe 3 O 4 nanoparticles are a very promising material for the extraction and separation of other similar natural drugs.