Amperometric immunosensor for lactate dehydrogenase LD-1.
An amperometric immunosensor for the detection of the lactate dehydrogenase isoenzyme LD-1 has been developed. Polyclonal antibodies for LD-1 have been covalently immobilised onto a preactivated Immunodyne ABC membrane, reacted with standard LD-1 solutions and placed onto a platinum working electrode polarised at +600 mV vs. Ag/AgCl. Lactate dehydrogenase activity has been measured by detection of the oxidation of NADH at the electrode surface. A calibration curve for LDH in the 0.005-0.12 U range has been obtained with a repeatability of 3% and a reproducibility of 10%. The probe exhibited good selectivity (response of LD-2 was 18% of LD-1) which was further improved using thermal treatment of the membranes. Measurement of LD-1 content in human control serum with the developed procedure gave a LD-1 concentration in the reported assigned range.
Kelly
S
S
Chemistry Department, University College Cork, Ireland.
Compagnone
D
D
Guilbault
G
G
D000818:Animals; D015374:Biosensing Techniques; D004563:Electrochemistry / Q000379:methods; D006801:Humans; D007118:Immunoassay; D007770:L-Lactate Dehydrogenase / Q000032:analysis*
D007770:L-Lactate Dehydrogenase