Bacteria Sensing Based on Multi-Mode Resonance at Microwave Regime

In this work, the two foodborne pathogens, E. coli and B. cereus, can be detected and discriminated with multi-mode resonance in the microwave region, 0.5 GHz to 10 GHz. To investigate the variation of the sensing parameters, resonant frequency, S
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-amplitude, and Q-factor, for bacteria detection and discrimination, the three configuration samples, LB, E. coli, and B. cereus, were tested on the sensor at a specific concentration of 0.01 OD/ml. According to the experimental results, the resonant frequency and S
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-amplitude variation of the test samples were more extensive, increasing the mode order from the first mode to the third mode resonance. However, the Q-factor gradually showed a reduced trend in the multi-mode resonance. In particular, three sensing parameters from the first mode to the third mode resonance exhibited a significant variation for discrimination between two kinds of bacteria.