Electrochemical L-lactic acid sensor based on immobilized ZnO nanorods with lactate oxidase.
In this work, fabrication of gold coated glass substrate, growth of ZnO nanorods and potentiometric response of lactic acid are explained. The biosensor was developed by immobilizing the lactate oxidase on the ZnO nanorods in combination with glutaraldehyde as a cross linker for lactate oxidase enzyme. The potentiometric technique was applied for the measuring the output (EMF) response of l-lactic acid biosensor. We noticed that the present biosensor has wide linear detection range of concentration from 1 × 10(-4)-1 × 10(0) mM with acceptable sensitivity about 41.33 ± 1.58 mV/decade. In addition, the proposed biosensor showed fast response time less than 10 s, a good selectivity towards l-lactic acid in presence of common interfering substances such as ascorbic acid, urea, glucose, galactose, magnesium ions and calcium ions. The present biosensor based on immobilized ZnO nanorods with lactate oxidase sustained its stability for more than three weeks.
Department of Science and Technology, Campus Norrköping, Linköping University, Norrköping, Sweden. zafar.hussain.ibupoto@liu.se
Zafar Hussain
ZH
Ibupoto
Syed Muhammad Usman Ali
SM
Shah
Kimleang
K
Khun
Magnus
M
Willander
D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000032:analysis*; D006899:Mixed Function Oxygenases / Q000737:chemistry / Q000378:metabolism*; D043942:Nanotubes / Q000737:chemistry*; D012666:Semiconductors; D013696:Temperature; D015034:Zinc Oxide / Q000737:chemistry*
D004800:Enzymes, Immobilized; D019344:Lactic Acid; D006899:Mixed Function Oxygenases; C021497:lactate 2-monooxygenase; D015034:Zinc Oxide