Physicochemical design of magneto-responsive confined interfaces for manipulation of nonmagnetic liquids

Controllable liquid manipulation is of paramount scientific and technological importance in various fields, such as the chemical industry, biomedicine, and agricultural production. Magnetic actuation, characterized by rapid, contactless, and environmentally benign operation, has emerged as a promising approach for precise liquid control. However, conventional magnetic strategies typically govern droplet movement on open surfaces, facing limitations such as restricted liquid volumes, uncertain flow paths, and inevitable evaporation, thereby constraining their broader practical applications. Recently, a variety of magnetic-driven strategies have been developed to dynamically regulate liquids within enclosed spaces, especially through physicochemical mechanisms. These approaches provide efficient control over liquid behavior by leveraging magnetically induced chemical changes, structural deformations, and dragging motions, opening new opportunities for flexible and versatile fluid management. This review explores the design and mechanisms of magneto-responsive confined interfaces for the manipulation of nonmagnetic liquids, highlighting key advancements and potential applications including liquid valves, liquid mixing, liquid flow regulation, and liquid pumping. Finally, the existing challenges and future prospects in this field are presented.