A “plug-n-play” modular microfluidic system is described herein which can be made by connecting multiple microfluidic components together to form a larger integrated system. For example, the modular microfluidic system includes a motherboard with interconnecting channels and integrated electrodes (or holes for electrodes to pass) which provide electronic connections to external data acquisition and system control devices. The modular microfluidic system can also include channel inserts (which are placed in the channels of the motherboard), heater units, actuator units, fitting components and microchips/modules with different functionalities which are placed on the motherboard.