A HIGH-THROUGHPUT ASSAY FORMAT FOR DETERMINATION OF NITRATE REDUCTASEAND NITRITE REDUCTASE ENZYME-ACTIVITIES

The authors describe a microplate-based high-throughput procedure for rapid assay of the enzyme activities of nitrate reductase and nitrite reductase, using extremely small volumes of reagents. The new procedur e offers the advantages of rapidity, small sample size-nanoliter volum es, low cost, and a dramatic increase in the throughput sample number that can be analyzed simultaneously. Additional advantages can be acce ssed by using microplate reader application software packages that per mit assigning a group type to the wells, recording of the data on expo rtable data files and exercising the option of using the kinetic or en dpoint reading modes. The assay can also be used independently for det ecting nitrite residues/contamination in environmental/food samples.