This phenomenon gave us a hint on our research: the law of entropy increase.
In the natural world, any system in an unstable state shifts to the most stable one, i.e., from a state with high free energy to that with the lowest. This natural phenomenon proceeds so as to minimize the entire free energy, and the lowest energy state is called the equilibrium. Especially in the micro world, every molecule moves to form a more disordered state toward the equilibrium. This movement is generated by the law of entropy increase.
Let’s think about the situation of spilling ink on water surface as an example. Soon after, the ink will diffuse into the whole water. On the other hand, it is impossible for the diffusing ink to get back together without any force from the outside. This is the effect of the law of entropy increase.
In this project, we propose a new kind of device made of tiny water droplets enclosed by lipid layer in oil phase, which can extract the free energy produced in the process of entropy increase as a proton (H+ ion) concentration gradient in a pair of droplets.
By using this proton gradient with F0F1ATPase, we will be able to produce ATP. All living things from bacteria to human beings use ATP (Adenosine Triphosphate) as an energy source. It can be said that this device works as a battery inside our body in that it supplies ATP. So we named the new device “Micro-Bio-Battery”.
For the first step, we tried to produce proton concentration difference between tiny water droplets.
