The Applications Of Nanocomposite Materials In Biosensors

Biosensors have been widely used in many fields such as food industry, environmentaland modern medicine due to their high sensitivity, intrinsic selectivity and rapid response.Furthermore, with the development of nanomaterial in recent years, biosensor has beenfurther research and development. In this paper, three kinds of glucose sensors were prepared,and applied to the determination of glucose. The results are satisfactorySeveral nanocomposite materials were prepared with different methods. They were usedfor the preparation of glucose biosensor (such as Nafion/GOx/MWNTs/ploy(Li-BTC)/GC、Nafion/GOx/ploy(DA)/Au/GC、Nafion/GOx/Pt/GN/GC). The electrochemical performancesof glucose on these modified electrodes were investigated by cyclic voltammetry. The resultsshow that Nafion/GOx/MWNTs/ploy(Li-BTC)/GC electrode showed preferable performancesto the determination of glucose. Comparing with references, it has lower detection limit,wider linear range and lower Michaelis constant characteristics. On theNafion/GOx/ploy(DA)/Au/GC electrode, it possessed higher electro-catalytic activity. Underthe optimum conditions of preparation and experimental, a wide linear range from0.005~to1.21mmol/L was obtained with a correlation coefficient0.999, and detection limit3.5mol/L (S/N=3:1), Michaelis constant was1.06mmol/L, much smaller than the value (22mmol/L) reported by literature,, it indicated that the immobilized GOx had good affinity toglucose. On the Nafion/GOx/Pt/GN/GC electrode, Pt nanoparticles were deposited on the GNbase by electrodeposition, and the response current of the modified electrode was notdecreased after seven days, which indicated that the sensor has long longevity.MWNTs/ploy(Li-BTC) and ploy(DA)/Au were first proposed by the ectropolymerizationand drop coating methods. And the electro-catalytic activities of the two nanocompositeswere discussed, respectively. The results show that two nanocomposites were good promotingeffect on the transfer rate of electrode, increasing the response current, and easy to operate.They will provide a new platform for fabricating electrochemical biosensor.