Enzyme-linked immunosorbent assay for quantitation of neomycin phosphotransferase II in genetically modified cotton tissue extracts

A double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed and validated to accurately quantitate neomycin phosphotransferase II (NPTII) levels in genetically modified cotton seed and leaf tissue. This assay provides a safer and more efficient alternative the the existing methods to measure NPTII levels in cotton tissue from genetically modified plants that contain NPTII as a selectable marker. Parallelism studies using purified bacterially-expressed NPTII and plant-expressed NPTII in the ELISA established that these proteins are immunologically conformationally equivalent