Electrochemical biosensor using dual electrode pair

Abstract

An electrochemical biosensor using a sensing system includes a working electrode including an active surface modified through a linker; and an auxiliary electrode. The sensor has a high current value compared with an existing sensor and retains excellent stability and sensitivity, and thus can be expected to be easily used for sensing various kinds of biomaterials.

1 . An electrochemical sensor for determining presence or concentration of an analyte in a fluid, comprising:
 a substrate; and   a working electrode formed on the substrate, and having an enzyme attached thereon by a linker.   
     
     
         2 . The electrochemical sensor of  claim 1 , wherein the linker is attached on nanoparticles directly formed on the electrode. 
     
     
         3 . The electrochemical sensor of  claim 2 , wherein the nanoparticles are selected from the group consisting of gold, platinum and palladium. 
     
     
         4 . The electrochemical sensor of  claim 1 , further comprising an auxiliary electrode formed to be separated apart from the working electrode in a horizontal direction of the substrate. 
     
     
         5 . The electrochemical sensor of  claim 1 , wherein the working electrode is formed to be separated apart from the substrate in a vertical direction, and has a mesh shape. 
     
     
         6 . The electrochemical sensor of  claim 5 , further comprising:
 an auxiliary electrode formed under the working electrode while having a space therebetween.   
     
     
         7 . The electrochemical sensor of  claim 1 , wherein the linker is formed by converting a functional group of a surface-modified base material including diazonium, a diazonium salt or a derivative thereof into an amine group, and then mixing the surface-modified base material with a dialdehyde crosslinking agent. 
     
     
         8 . A method of manufacturing an electrochemical sensor, comprising:
 forming an electrode on a substrate;   forming a surface-modified base material on the electrode;   reacting the surface-modified base material and a crosslinking agent; and   reacting the reacted crosslinking agent and an enzyme, thereby attaching the enzyme on the electrode.   
     
     
         9 . The method of  claim 8 , wherein the surface-modified base material is diazonium, a diazonium salt or a derivative thereof. 
     
     
         10 . The method of  claim 9 , wherein the surface-modified base material is 4-nitrophenyl diazonium tetrafluoroborate (4-NP). 
     
     
         11 . The method of  claim 8 , wherein the crosslinking agent is dialdehyde. 
     
     
         12 . The method of  claim 11 , wherein the crosslinking agent is glutaraldehyde. 
     
     
         13 . The method of  claim 8 , further comprising:
 forming nanoparticles on the electrode,   wherein the surface-modified base material is directly formed on the nanoparticles.