Development of Blood Extraction System for Bio-MEM

Abstract

A compact and wearable blood sampling medical device applied for Bio-MEM (Biomimetic-Medical Electronics Machine) such as a health monitoring system (HMS), was newly developed. This medical device for Bio-MEM designed by female mosquito's blood sampling mechanism, can extract human blood in order to detect blood sugar level for diabetic patient. This device consists of (1) a bio-compatible microneedle indentation unit using a shape memory alloy (SMA) actuator, (2) a pumping unit using a bimorph PZT piezoelectric actuator and (3) a MOSFET type biosensor by employing Glucose oxidase (GOX) enzyme. The performances of elements were evaluated as ; (1) indentation force of the microneedle using the SMA actuator and (2) blod sampling ability of the pumping unit using the PZT actuator were measured, and the pressure to extract blood by female mosquito was simulated. The indentation load generated by SMA actuator was 0.8 N. The medical device with the PZT actuator, extracted human blood at the flow rate of 2μl/min. The pressure generated by PZT actuator and the simulated famale mosquito's pressure were 11 kPa and 7 kPa, respectively. A Titanium microneedle with the size of a female mosquito's labium (60μm external diameter and 25μm internal diameter) was produced by the sputter deposition method.