Optimizing the functionalization process for nanopillar enhanced electrodes with GOx/PPY for glucose detection

Abstract

In this study, the functionalization process for nanopillar enhanced electrodes (NEEs) using glucose oxidase (GOx) with polypyrrole (PPY) is optimized for the purpose of achieving enhanced sensing performances for these electrodes in glucose detection. Specifically, an optimal roughness factor for the NEEs and an optimal set of electro-polymerization/deposition parameters for their functionalization using GOx/PPY are identified. Results show that NEEs with a roughness factor of about 60 are optimal for enhancing the amperometric current responses and that for such electrodes an electro-functionalization/deposition process at a deposition current of 50 µA cm(-2) and a total charge of 150 mC cm(-2) will give rise to a high sensing performance with a sensitivity as high as 36 µA cm(-2) mM(-1).

Conducting polymer nanostructures and their application in biosensors

“…A sensitivity for specific targets of 10 ng/ml was achieved [126]. Nanopillar enhanced electrodes (NEEs) functionalized by glucose oxidase (GO x ) and PPy have also been employed to achieve enhanced sensing performances in glucose detection [127]. The NEEs with a roughness factor of about 60 were optimal, which led to high sensing performance for glucose detection with a sensitivity as high as 36 lA cm À2 mM À1 .…”

Design and Fabrication of 3D Skyscraper Nanostructures and Their Application as Electrodes in Biosensors

“…In an electrochemical based biosensor, the sensitivity is related to the surface area of its electrode (Bard et al, 2001;Delvaux et al, 2003) because a large surface area is beneficial not only for enzyme immobilization but also for electron transfer. The surface area of the electrode can be increased by the use of nanostructures because the surface-to-volume ratio of a structure increases as its size decreases (Jia et al, 2007;Anandan et al, 2007, Gangadharan et al, 2008. Since most of these nanostructures are made of inorganic materials, to use them as electrodes they have to be functionalized for biological recognition purposes (Gangadharan et al, 2008;Lee et al, 2008).…”

“…The surface area of the electrode can be increased by the use of nanostructures because the surface-to-volume ratio of a structure increases as its size decreases (Jia et al, 2007;Anandan et al, 2007, Gangadharan et al, 2008. Since most of these nanostructures are made of inorganic materials, to use them as electrodes they have to be functionalized for biological recognition purposes (Gangadharan et al, 2008;Lee et al, 2008). To functionalize these electrodes, biosensitive elements need to be immobilized onto the electrode surface.…”

“…Physical entrapment of an enzyme in a porous conducting polymer film at electrode surface offers an attractive alternative. Conducting polymer like polypyrrole (PPy) can be electro-polymerized and deposited onto the electrode surface to form a porous film, providing pores large enough for efficient electron transfer (Ramanavicius et al, 2001;Gangadharan et al, 2008). Thus by mixing an enzyme in pyrrole solution, a porous polymeric film with the enzyme entrapped inside can be formed at electrode surface via electrodeposition.…”

Role of SAM Chain Length in Enhancing the Sensitivity of Nanopillar Modified Electrodes for Glucose Detection

“…Since most of these nanostructures are made of inorganic materials, they have to be functionalized for biorecognition purposes [7, 8]. To functionalize these electrodes, biosensitive molecules such as enzymes need to be immobilized onto the electrode surface through the use of anchoring molecules.…”