OPTICAL IMMUNOSENSING OF LACTATE-DEHYDROGENASE (LDH)

Detection of the lactate dehydrogenase (LDH) enzyme is important in ma ny areas of clinical diagnosis. A fibre-optic evanescent wave immunose nsor (EWIS) was developed for the determination of this enzyme. A poly clonal antibody preparation was used in both one-step and two-step ass ays, developed for the analysis of LDH. Similar assays were performed on the commercially available biosensor based on surface plasmon reson ance, the BlAcore(TM), and the results compared to those obtained with the EWIS. It was established that although the same polyclonal antibo dy preparation can be used for one-step immunoassays, if the antigen i s large, the sensitivity of the sensor system is reduced when compared to two-step assays. The working ranges for both systems were determin ed. (C) 1997 published by Elsevier Science S.A.