Glucose Sensors Based on Glucose Oxidase Immobilized in Polypyrrole-Polyacrylamide Microparticles
E. López-Cabarcos, J. Rubio-Retama, D. Mecerreyes and B. López-Ruiz
University Complutense, ES
Keywords: polyacrylamide-polypyrrole microparticles, immobilization of glucose oxidase, glucose biosensors
Soluble, polypyrrole has been synthesized by the incorporation of the sulphonate dopant anion which renders the polymer soluble in water. The soluble polypyrrole was incorporated in the aqueous phase of a W/O concentrated emulsion, together with different amounts of the monomer acrylamide and the crosslinker bisacrylamide. The polymerization of the aqueous dispersed phase produces microparticles with average size 4.5 mm in which the soluble polypyrrol is entrapped. The microparticles with 50/50 (w/w) polypyrrole/polyacrylamide exhibited conductivities up to 110-5 S/cm in the range of semiconductor materials. Glucose Oxidase (GOx) was immobilized in 50/50 polyacrylamide/polypyrrole microparticles by incorporating the enzyme in the aqueous phase of the concentrated emulsion before starting the polymerisation. The microparticles with immobilized enzyme were used as biological component of an amperometric glucose sensor that responds to glucose under aerobic and anaerobic conditions demonstrating a possible application of the conducting microparticles as well as the effectivity of the immobilization technique.
Nanotech 2004 Conference Technical Program Abstract