Bio-actuated, especially flagellated bacteria-driven, micro/nanorobots have been actively studied to develop novel technologies such as drug delivery systems (DDS), though the characteristics of the actuator (flagellar motor) have not been sufficiently investigated. For analysis or control of the bacterial flagellar motor, we previously proposed the local environmental control system with nano/micro dual pipettes to dynamically generate arbitrary local ion/reagent concentration change. In the result, transient-state and steady-state of local Na+concentration were manipulated with high facultativity. However, in this system, over time, the local ion/reagent could not be fully flushed out due to the increase of the diffusion rate caused by high external (in the bath) ion/reagent concentration. Therefore, in this paper, to achieve more arbitrary local environmental control, we propose the local environmental control system by combination of microfluidic chip with world-to-chip interface (WtCI) and pipette. We fabricate the WtCI microfluidic chip by two-step photolithography, and develop the system by using precisely controllable syringe pump. And, we demonstrate the basic feasibility of the local environmental control system by combination of WtCI microfluidic chip and pipette.

Micro/Nano robots have attracted scientific attention to develop novel technologies such as drug delivery systems. Recently, flagellated bacteria have been used as the driving force of microobjects to develop bacteria-driven microrobots. In this paper, we propose a method of smart manipulation of multiple bacteria-driven microobjects with single manipulated guiderobot based on bacterial autonomous movement, named ¿SMARTBOT¿, for enabling arbitrary and low cost manipulation of multiple bacteria-driven microrobots. We verify the capability of smart manipulation of multiple bacteria-driven microobjects based on bacterial autonomous movement by using micro/nano pipettes instead of a guiderobot. For the fabrication of the guiderobot and the cargo driven by the bacteria, the fabrication of the arbitrarily-shaped microobjects using photo lithography technique is demonstrated. Additionally, we demonstrate the remote control using optical tweezers and driving using flagellated bacteria of the fabricated arbitrarily-shaped microobjects.

Micro/nano robots have been actively studied toward the realization. Now, the micro living organisms have been used as the driving forces for the micro objects. To achieve the fine manipulation of bio driven micro objects, the manipulation methods have to be established. Therefore, the local environmental control technique is desired to manipulate a single cell and to analyze the detailed properties. We have developed the local environmental control system with nano/micro dual pipettes, and achieved the quick-response and iterative rotational speed manipulation of Na+-driven flagellar motor, which is a rotary molecular machine, by switching the local spout between Na+-containing and Na+-free solutions with dual pipettes. In this paper, we upgrade our local environmental control system with nano/micro dual pipettes to achieve the quantitative and long-time-stable manipulation of the rotational speed of the Na+-driven flagellar motor. We demonstrate fine and long-time-stable rotational speed manipulation of Na+-driven flagellar motor by simultaneous local spouts of Na+-containing and Na+-free solutions using dual pipettes with controlling the spouting velocities independently. And, as the driving force, the rotational torque generated by the flagellar motor is estimated at the range from ~2.3×103to ~2.8×103pN·nm.