Rotation of biological cells: fundamentals and applications

Cell rotation is one of the most important techniques for cell manipulation in modern bioscience, as it not only permits cell observation from any arbitrary angle, but also simplifies the procedures for analyzing the mechanical properties of cells, characterizing cell physiology, and performing microsurgery. Numerous approaches have been reported for rotating cells in a wide range of academic and industrial applications. Among them, the most popular are micro-robot-based direct contact manipulation and field-based non-contact methods (e.g., optical, magnetic, electric, acoustic, and hydrodynamic methods). This review first summarizes the fundamental mechanisms, merits, and demerits of these six main groups of approaches, and then discusses their differences and limitations in detail. We aim to bridge the gap between each method and illustrate the development progress, current advances, and prospects in the field of cell rotation.