Effect of APTES Percentage towards Reduced Graphene Oxide Screen Printed Electrode Surface for Biosensor Application

Abstract Graphene and its derivatives are popular material nowadays among researchers due to its interesting mechanical, electronic and structural properties. Although pristine graphene have high electrical conductivity, some biosensor application require modified form of graphene such as graphene oxide or reduced graphene oxide because easier attachment of linker due to their oxide layer availability. Common functionalization method is using APTES as a linker that attach to working electrode of screen printed electrode. Certain percentage of APTES will then bind with targeted biomarker. Here, silanization of 2%, 4%, 6%, 8% and 10% APTES were conducted on the surface of reduced graphene oxide screen printed electrode to study the effect of APTES percentage towards reduced graphene oxide surface for stable biosensor platform. The 2% APTES shows stable current result of 0.111µA and potential of 0.18V at 100mV/s. This result significant for concentration to surface area ratio whereby low concentration produced higher surface area and lower resistance for electron transfer.