A vortex-enhanced magnetic solid phase extraction for the selective enrichment of four quaternary ammonium alkaloids

Li Li1, Danhui Zhao1, Kun-Ze Du1

  • 1State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China; Tianjin Key Laboratory of Phytochemistry and Pharmaceutical Analysis, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China.