Table 2.

Comparison of typical driving methods.

Driving Method	Control				Remarkable Superiority	Demerit
	Biological Penetration	Swarm	Separate from Swarm	Remote
Magnetic	√	√	×	√	Excellent biological safety and penetration 3D collective manipulation	Complex and massive electromagnetic field equipment Cannot manipulate special target from a swarm
Light	Difficult	√	√	√	Enabling simultaneous and separate manipulation because of variable parameters (wavelength, intensity and phase et al.)	Poor biological penetration
pH	×	√	×	×	Simple and convenient operation	Most pH value is lethal to living cells or organisms
Microforce	×	Difficult	√	×	Universal for most materials	Must contact
Heat	Difficult	√	Difficult	√	Universal for most materials	Cannot manipulate special target from a swarm
Solution	×	√	×	×	Simple and convenient operation	Poor biocompatibility
Acoustic	√	√	Difficult	√	Excellent biological safety and penetration	Control precision Z-axis manipulation
Electric	×	√	√	√	Easy to integrate with mature IC	Functional materials and corresponding structures are difficult to miniaturize