Highly Sensitive Detection of Cucumber Mosaic Virus by Using Fluorogenic Substrate or Enzyme-Amplified Assay in Enzyme-Linked Immunosorbent Assay

Monoclonal antibody (MAb) was applied to a double-antibody sandwich ELISA (DAS ELISA) for highly sensitive detection of cucumber mosaic virus. Alkaline phosphatase-labeled MAb with high activity was used to raise the ratio of spocific-and nonspecific-adsorption of conjugate (S/N ratio) on polyclonal antibody coated solid phase. Also the assay with a fluorogenic substrace or an enzyme-amplified assay which is highly sensitive for measurment of activity was employed to increase the sensitivity of the assays. This ELISA systems proved to be more sensitive than the conventional assay using ρ-nitorophenyl phosphate, and could detect 100 pg/ml of purified virus.