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Updated: Feb 14, 2026
Bacterial Detection & Identification Using Electrochemical Sensors
Published on: April 23, 2013
Robust Ionic Current Sensor for Bacterial Cell Size Detection
Hirotoshi Yasaki, Taisuke Shimada, Takao Yasui1
1Japan Science and Technology Agency (JST), PRESTO , 4-1-8 Honcho , Kawaguchi , Saitama , 332-0012 , Japan.
Abstract:
Ionic current sensing methods are useful tools for detecting sub- to several-micron scale particles such as bacteria. However, conventional commercially available ionic current sensing devices are not suitable for on-site measurement use because of inherent limitations on their robustness. Here, we proposed a portable robust ionic current sensor (Robust-ICS) using a bridge circuit that offers a high signal-to-noise (S/N) ratio by suppressing background current. Because the Robust-ICS can tolerate increased noise in current sensing, a simple, lightweight electromagnetic shield can be used and measurements under large electromagnetic noise conditions can be made. The weight of the device was lowered below 4 kg and outdoor particle detection measurements were completed successfully. Accuracy of size detection of Staphylococcus aureus ( S. aureus) was equivalent to that obtained by SEM imaging.
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