Optimized polymer-coated QCR for real-time, on-line detection of organic compounds in water

QCRs (quartz crystal resonators) coated with various polymers which show stability in water and sensitivity to organic contaminant molecules are investigated as chemical sensors in liquid environments. The main detection mechanism is based on the mechanical loading which is believed to be primary mass loading. Detection limits of 150 ppb and 500 ppb are demonstrated with reproducibility for tetrachloroethane and trichloroethene, respectively, using poly (ethyl acrylate)-coated QCRs. The low detection limits with response time less than two minutes indicate that the devices can be used for real time analysis of contaminant in water. The results are discussed in terms of the partition coefficients of the analyte molecules which could be utilized in the implementation of sensor arrays for practical applications