Glucose driven drug release system using improved decompression unit

In this work, an enhanced performance of an enzymatic chemo-mechanical actuator that can convert the chemical energy of glucose into mechanical energy for autonomous drug release without an electrical power is reported. The novel biochemical approach is based on increasing the decompression rate in a "vacuum unit" by fabricating enzyme co-immobilized membrane by multiple enzymes. Among the enzymes (glucose oxidase (GOD), pyranose oxidase (POD), alcohol oxidase (AOD)), which can oxidize glucose and/or glucono-1.5-lactone evaluated in co-immobilization designs within the vacuum unit, the highest decompression was obtained with POD+GOD, which was 3 times higher than that of the conventional organic engine with only GOD. Furthermore, the decompression rate of -7.4 Pa·cm³/sec in the vacuum unit necessary to drive the drug release system was obtained at 10 mmol/L glucose, which is close to the human blood sugar level. In conclusion, the vacuum unit is a promising device for development of a chemomechanical system driven by human blood sugar for the diabetes treatment.