A power-free surface-tension-driven fluidic network system for large-array enzyme immobilization and glucose sensing

A novel fluidic network system for batch enzyme-immobilization and glucose sensing has been proposed in this paper. This fluidic network comprises an enzyme chip for sensor and enzyme accommodation, and a fluid chip for blood sample introduction. Polymer-MEMS technologies, including SU-8 lithography and PDMS molding, have been employed for the chip fabrication. Oxygen-plasma treatment is utilized to provide channel surface hydrophilic property, which is the key for fluids driven passively without external power sources. Operated by simple sample drop-in and withdraw process, enzyme deposition can be precisely controlled in both position and amount. The dose uniformity of the enzyme deposition, better than ±10% in each sensor compartment, has been achieved by employing a H-shaped fluidic system. Functional glucose-sensor-response of 5.42 nA/mM. with minimum sensible signal of 8 mM has also been demonstrated in this study.