Kinesin-based molecular motors for cargo transportation in nanotechnology
- Contact Researcher: Celine BOTTIER, Dr.
- Hosted LIMMS Japanese Laboratory: FUJIITA Lab.
- biomolecular motors
- direct transportation
- oil droplets
- Context :
Biomolecular motors, such as the motor protein kinesin, are highly efficient nanoscale engines that have proven their usefulness in a wide range of biological processes such as motility, cell division or intracellular transport . Kinesin convert the chemical energy derived from the hydrolysis of ATP (adenosine 5’-triphosphate) into mechanical work allowing them to move along filamentous tracks called microtubules. The ability to produce and isolate these motors using standard methods of biotechnology permits the design of hybrid devices, where biomolecular motors serve as force-generating modules in an artificial environment.
- Objectives :
The potential to use motor protein-driven transport in various nanotechnological applications has been suggested by several authors. The suggested applications include sorting, nanoseparation and unidirectionnal cargo transportation in a lab-on-a-chip [2, 3] (Figure 1), assembly of molecular components [4, 5], and micro- and nanomechanical devices . However, most of these suggestions are rather long-term and no commercially viable product has yet been developed. This represents a real challenge because molecular motors should offer important advantages compared to microfluidics and nanofluidics. Unlike in these latter systems, motors provide a means of transportation that is independent of pressure-driven flow or electrokinetic transport. Particularly in nanofluidics, pressure-driven transportation becomes increasingly difficult since flow per cross-sectional area, i.e., velocity, is proportional to the square of the channel radius for a given pressure difference. Motors, on the other hand, are not bound by these size limitations. Thus, the incorporation of these molecular motors into synthetic nanodevices may form the basis for lab-on-a-chip systems of unprecedented miniaturization and complexity.
- Methods :
The present research proposes a complete system to transport (using biomolecular motors) and fuse oil droplets (oil-in-water emulsion). As nanoparticles  or even lipophilic molecules  can be encapsulated within the droplets, direct transportation of those droplets allows us to carry different materials in different droplets and bring them into contact to fuse with electrical field allowing particles to interact without any liquid manipulation. The overall schematic view of the proposed system is represented in Figure 2. Basic components of this system are the transportation of the kinesin-coated oil droplets along microtubules and electrofusion of these droplets. The feasibility of these two main components has been demonstrated 
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Figure 1: Schematic view of the transportation of a cargo using the kinesin/microtubule system. Figure 2: Overall view of the proposed system: microtubules,oriented in the PDMS channel, along which oil droplets are transported.
When the droplets come together in the main channel,voltage is applied on the electrodes to fuse them