Whole cell imprinting based Escherichia coli sensors: A study for SPR and QCM

The detection of pathogenic bacteria is essential for a sustainable prevention of water quality and by this way prevention of life threatening illnesses. It is important to use rapid methods for pathogenic bacteria detection but traditional detection methods may take up to a whole week. In this report, we describe a molecular imprinting based bacteria sensor via whole cell imprinting for rapid detection of bacteria from water sources. Here, Escherichia coli (E. coli) is selected as model bacteria because of it is one of the most abundant pathogenic bacteria in ground water sources and may cause severe illnesses. The presence of E. coli in the water sources is an indicator of urban and agricultural runoffs, so monitoring E. coli contamination is important to preserve quality of the water sources. Traditional detection methods for E. coli include genomic analysis, antibody based assays, culture methods, fluorescence and microscopy. Disadvantages of traditional bacteria detection methods induce many researches on other detection methods like biosensors. In this study, a new label-free rapid and selective detection method was developed via micro contact imprinting of whole cell on both optical and mass sensitive devices. The amino acid based recognition element, N-methacryloyl-l-histidine methylester (a polymerizable form of histidine) was used in this study to obtain similar recognition as in natural antibodies.