Real-time detection of chlorpyrifos at part per trillion levels in ground, surface and drinking water samples by a portable Surface Plasmon Resonance immunosensor
E. Mauriz, A.Calle, L. M. Lechuga, J. Quintana, A. Montoya and J. J. Manclús
Anal. Chim. Acta, 561, 2006, 40-47 - DOI: 10.1016/j.aca.2005.12.069
Abstract: Development of a portable surface plasmon resonance immunosensor for continuous monitoring of chlorpyrifos residues in water is reported. The sensor, which was contructed using a commercial β-surface plasmon resonance sensor system. A chlorpyrifos derivative immobilized on a gold-coated sensing surface competed with analyte in the sample for antibody in the immunoassay and formation of alkanethiol self-assembled monolayers ensured that the sensor could be reused. Assay variability and sensitivity were evaluated: for chlorpyrifos-spiked samples of groundwater, river water or drinking water limits of detection values were in the range 45–64 ng/ml and recoveries of 80–120% were achieved. Good agreement was found between results obtained with the developed sensor and GC-MS (r = 0.995).