A closed-loop micropump and flow meter for high-precision drug delivery in an implantable neural probe

In this study, a closed-loop micropump system and flow meter with a proportional-integral-derivative (PID) controller is introduced to improve the accuracy of flow rate measurement and drug delivery. The micropumps are fabricated using Polydimethylsiloxane (PDMS) and have a drug reservoir capacity of 7µL. A capacitance-based flow meter is employed as the feedback mechanism for the PID controller. The flow rate range investigated is between 15 to 45 pL/min, with a resolution of 1.2 pF per 100 pL/min. The implementation of the PID controller enhances the accuracy of drug delivery by up to 27%.