1994 Volume 43 Issue 5 Pages 389-394
We have developed a chemiluminescent assay for glucose-6-phosphate dehydrogenase (G6PDH) and alkaline phosphatase (ALP) using NADH oxidase (NOD) purified from S. mutans, and an ALP assay system applied to enzyme immunoassay. Regarding the assay for G6PDH, we could measure a range covering 1.0μU/ml to 0.5mU/ml. The detection limit was 1.0×10-18mol/assay by the 2SD method. On the other hand, when we used an enzyme-cycling system with alcohol dehydrogenase (ADH) and NOD, we could measure from 20 fM to 10 pM of ALP, and the detection limit was 4.0×10-19mol/assay by the 2SD method. We applied this ALP assay system to an enzyme immunoassay for hCG; its measuring range was 0.2100 mIU/ml in serum. The hCG assay gave good results for both inter and intra assays, a dilution test and a recovery test. It also gave a good correlation with a Delfia hCG kit in a TR-FIA assay; we could measure 9 samples below 1.0 mlU/ml, which was the detection limit of the Delfia hCG kit. We had confirmed NOD is a useful enzyme on EIA, and so on.
