Development of a screen-printed amperometric biosensor for the determination of L-lactate dehydrogenase level.
We attempted to develop a screen-printed biosensor for the amperometric determination of L-lactate dehydrogenase (LDH) level on the basis of NAD(+)/NADH-dependent dehydrogenase reaction. The printing ink for the working electrode consisted of L-lactate, NAD(+), composite polymer of hydroxyethyl cellulose with ethylene glycol, 3,4-dihydroxybenzaldehyde (3,4-DHB) as an electron transferring mediator, and graphite as the conducting material. The 3,4-DHB was electropolymerized on the carboneous working electrode by potential cycling between -200 and +300 mV vs. Ag/AgCl reference electrode. Through the electrocatalytic reaction with immobilized 3,4-DHB, the NADH generated by the LDH reaction could be efficiently oxidized at lower potential than the unmodified carbon electrode. The analytical performance of the electrode was characterized in terms of linear sensing range and detection limit for LDH. The response from the developed biosensor was linear up to 500 U/l of LDH, and the detection limit of 50 U/l was observed at the signal-to-noise ratio of 3.
Hong
Mi-Young
MY
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Kusung-dong, Yusung-ku, Taejon 305-701, Republic of Korea.
Chang
Je-Young
JY
Yoon
Hyun C
HC
Kim
Hak-Sung
HS
D015374:Biosensing Techniques / Q000379:methods*; D002384:Catalysis; D004563:Electrochemistry; D007770:L-Lactate Dehydrogenase / Q000032:analysis*
D007770:L-Lactate Dehydrogenase