Submitted to: American Chemistry Society Book Chapter
Publication Type: Book / chapter
Publication Acceptance Date: 7/1/2007
Publication Date: 7/1/2007
Citation: Kramer, P.M., Weber, C.M., Kremmer, E., Rauber, C., Martens, D., Forester, S., Stanker, L.H., Rauch, P., Shiundu, P.M., Mulaa, F.J. 2007. Optical immunosencor and Conventional Elisa for the Analysis of Pyrethroids and DDT in Environmental Samples. Kennedy I.R., Solomon K., Gee S., Crosnan A., Wang S. 1ST Edition. New York, NY: University Press. p. 186-202. Interpretive Summary: Contamination of water with pesticide residues can be found throughout the world. There is an urgent need, especially in developing countries, to provide cost-effective tools for on-site pesticide screening to support control. For this purpose a new sensor (AQUA-OPTOSENSOR) using monoclonal antibodies (mAbs) was developed for two pesticides, pyrethroids and DDT. This sensor consists of an instrument, controlled by a laptop computer, and a single-use chip. It measures emission of fluorescent light and the amount of light emitted is inversely proportional to the pesticide concentration in the sample. Using this technique, it will be possible to monitor pollution in water matrices without cost-intensive laboratory analysis. Advantages and limitations of this technology will be discussed.
Technical Abstract: An optical immunosensor (AQUA-OPTOSENSOR) and conventional ELISA (enzyme-linked immunosorbent assay)for the analysis of pyrethroids and DDT in environmental samples, namely river water and/or sediment, are described. The optical immunosensor consists of a bench-top optical read-out-device and disposable single-use sensor chips. Conventional ELISA was carried out in the coating antigen format. As examples, phenothrin (pyrethroid) and p,p’-DDT were chosen. Herein we describe the overall strategy, the set up and principle of the immunosensor platform, and show representative results for immunosensor and ELISA analysis. The immunosensor employs fluorophore (Oyster®-645)- labeled monoclonal antibodies (mouse mAb Py-1 and rat mAb DDT 7C12), and makes use of the evanescent field, thus operating without washing steps. ELISA uses a second antibody labeled with peroxidase. Both, phenothrin and p,p’- DDT can be analyzed with these immunochemical techniques in the low ppb level, respectively. A selection of applications with this immunosensor and/or conventional ELISA is shown with river water samples and with sediment samples. Advantages and drawbacks of both immunochemical platforms are discussed.