Constant Glucose Biosensor Based on Vertically Aligned Carbon Nanotube Composites

摘要

In this contribution, a reagent free glucose biosensor was prepared based on multi walled carbonnanotubes (MWCNTs) composite via the electrochemical method. The synthesized MWCNTs were inturn successfully optimized by the chemical vapor deposition (CVD) method. The glucose oxidase(GOx) was immobilized on a carbon nanotubes/gelatin (Gl) composite using the entrapment technique,-1 with an 8.42 s direct electron transfer rate between GOx and MWCNTs/Gl, which was then drop- casted onto a glassy carbon electrode (GCE). The bioactivity of GOx on modified GCE was retainedduring the electrochemical reactions. The cyclic voltammetric results coupled with thechronoamperometric response and obtained from modified GCE indicated that aGOx/MWCNTs/Gl/GC electrode can be utilized as a glucose biosensor via its display of highsensitivity and stability. The biosensor exhibited a wide linearity range to 8.9 mM glucose, with thedetection limit of 0.54 mM and a stability of 75.4% current diminish after 25 days. The proposedfabrication method of glucose biosensor was in line with the developments of electrochemical researchfor glucose determination of human serum in the context of electrochemical reactions. The resultsindicated that the biosensor possessed good stability and acceptable fabrication reproducibility.