The Application Of Novel Nano-materials In The Electrochemical Sensors

In this paper, Three kinds of electrochemical sensor was made:Frist, by controlling the synthesis conditions,Nickel hydroxide nanoflowers(f-Ni(OH)2)and Ni(OH)2 nanosheets(s-Ni(OH)2) had been fabricated successfully; both kinds Nickel hydroxide have electrocatalytic electrocatalytic effect on glucose.Then the nanopowders which dispersed in different dispersing agents were dropped onto the surface of glassy carbon electrode(GCE) to form a modified electrode. The modified electrodes constructed an excellent non-enzymatic glucose sensor.Non-enzymatic glucose sensor that modified by s-Ni(OH)2 has a wide linear range from 0.25 to 39.26 m M, which is superior to commercial blood glucose test strips, and showing high precision of the sensor in measuring of glucose in serum. The sensor modified by f-Ni(OH)2 has a lower oxidation potential of glucose(0.39 V vs.SCE) than s-Ni(OH)2(0.55 V vs.SCE), thus it has a better anti-interference performance in serum.Then, to prepare the stable PDDA-CNTs aqueous dispersion,Poly(diallyldimethylammonium chloride)(PDDA) was chosen to disperse multi-walled carbon nanotubes(MWCNTs), and the positively charged PDDA-MWCNTs composite and negatively charged glucose oxidase(GOx) were employed to fabricate multilayer films on glassy carbon electrodes by layer-by-layer self-assembly technique. The optimum assembly number was 4 The bacteriostatic film that N-(3-sulfopropyl)-N-methacryloxyethyl-N,Ndimethylammonium betaine(DMAPs) dispersed in Graphene(DMAPs-GR) was dropped at the end of the last muhilayer films.The results showed that MWCNTs can evenly dispersed in the PDDA films and the multilayer films(PDDA-MWCNTs) can improve the catalytic current response to Glucose(Glu) significantly. The glucose biosensor fabricated showed good linearcorrelation from 0.016 M to 0.281 M, and the corresponding regression equation of the linear plot respectively was I/μA = 0.185 + 0.640* c, R2= 0.99,N= 22, The sensitivity was thus estimated as 0.0.64 μA M-1, the detection limit(S/N = 3) were determined to be 7.14 m M. Moreover,the biosensor exhibited an excellent bacteriostatic property and a good stability. There is potential for monitoring the concentration of glucose in the fermentation industry.