Based on the technology of micro-fluidics digitalization

a new method of preparing cell microcapsules is proposed.The method has the advantage of simple structure

low cost

and mild preparation conditions.A pulse driving and controlling system of micro-fluidics was designed based on electromagnet actuator.Pulse inertial force with controllable size and frequency was applied to a micro-nozzle and sodium alginate cell suspension inside the nozzle through controlling the reciprocating magnetic core

which bumped a vibrating object

to which the micro-nozzle was fixed.By using this method

a single fish roe cell (about 900μm）was injected steadily and cell microcapsules were prepared stably.Optimum parameters for stable preparation were determined.The parameters included clamping angle of micro-nozzle θ

voltage amplitude U

frequency f and length of liquid column L.The prepared fish roe cell microcapsules had uniform wall-thickness

regular shape and good monodispersity.The size of microcapsules could be changed by choosing micro-nozzles with different inner diameters.The viability of microencapsulated cells was indirectly measured by trypan blue stain solution and the result was approximately 90%.