Amperometric Glucose Biosensor Based on a Pt-Dispersed Hierarchically Porous Electrode

초록

A high-performance electrochemical biosensor for the detection of glucose was developed using a Pt-dispersed polyaniline (PANI) nanorod electrode with a hierarchical porous surface. PANI nanorods were synthesized directly on an Au-coated porous silicon electrode and high-density Pt nanoparticles were dispersed on the PANI nanorods by electrochemical deposition. The electrode surface's structure exhibited order on multiple length scales from similar to 30-nm Pt nanoparticle to similar to 200-nm diameter PANI nanorod to micrometer pore size's for the porous silicon. The sensitivity of the Pt-dispersed PANI nanorod electrode with a hierarchical porous surface was 35.64 mu A/mM, which corresponds to a 22.1-fold larger value than that of the planar Au/PANI nanorod electrode. The glucose biosensor with a Pt-dispersed highly porous electrode exhibited a short response time (<10 s) and a linear response in the range from 9 x 10(-6) to 5 x 10(-3) M. The sensor also showed long-term stability; the sensing response measured under the same conditions retained 80 % of the initial value after a 45-day storage. The high performances of the novel glucose sensor are mainly attributed to the hierarchical porous electrode structure, which provides an increased sensing area and effective mass transportation pathway.

키워드