Auto-regulated medical pump without energy supply

The authors fabricated an osmotic pump using semipermeable membrane which changes its volume according to outside concentration of solution without any energy supply and regulation system. This pump directly converts chemical potential to mechanical action without an intermediary like an electrical apparatus: it is is called a mechanochemical actuator. The authors applied this mechanism for an insulin pump driven by changing glucose concentration. It was demonstrated that this pump has the possibility of being applied to treat diabetes mellitus patients