Soft Hydrogel Actuator for Fast Machine-Learning-Assisted Bacteria Detection

We demonstrate that our bio-electrochemical
platform facilitates
the reduction of detection time from the 3-day period of the existing
tests to 15 min. Machine learning and robotized bioanalytical platforms
require the principles such as hydrogel-based actuators for fast and
easy analysis of bioactive analytes. Bacteria are fragile and environmentally
sensitive microorganisms that require a special environment to support
their lifecycles during analytical tests. Here, we develop a bio-electrochemical
platform based on the soft hydrogel/eutectic gallium–indium
alloy interface for the detection of Streptococcus
thermophilus and Bacillus coagulans bacteria in various mediums. The soft hydrogel-based device is capable
to support bacteria’ viability during detection time. Current–voltage
data are used for multilayer perceptron algorithm training. The multilayer
perceptron model is capable of detecting bacterial concentrations
in the 104 to 108 cfu/mL range of the culture
medium or in the dairy products with high accuracy (94%). Such a fast
and easy biodetection is extremely important for food and agriculture
industries and biomedical and environmental science.