The EcoChip: A Wireless Multi-Sensor Platform for Comprehensive Environmental Monitoring

Abstract

This paper presents the EcoChip, a new system based on state-of-the-art electro-chemical impedance (EIS)technologies allowing the growth of single strain organisms isolated from northern habitats. This portable system is a complete and autonomous wireless platform designed to monitor and cultivate microorganisms directly sampled from their natural environment, particularly from harsh northern environments. Using 96-well plates, the EcoChip can be used in the field for realtime monitoring of bacterial growth. Manufactured with highquality electronic components, this new EIS monitoring system is designed to function at a low excitation voltage signal to avoid damaging the cultured cells. The high-precision calibration network leads to high-precision results, even in the most limiting contexts. Luminosity, humidity and temperature can also be monitored with the addition of appropriate sensors. Access to robust data storage systems and power supplies is an obvious limitation for northern research. That is why the EcoChip is equipped with a flash memory that can store data over long periods of time. To resolve the power issue, a low-power microcontroller and a power management unit control and supply all electronic building blocks. Data stored in the EcoChip's flash memory can be transmitted through a transceiver whenever a receiver is located within the functional transmission range. In this paper, we present the measured performance of the system, along with results from laboratory tests in-vitro and from two field tests. The EcoChip has been utilized to collect bio-environemental data in the field from the northern soils and ecosystems of Kuujjuarapik and Puvirnituq, during two expeditions, in 2017 and 2018, respectively. We show that the EcoChip can effectively carry out EIS analyses over an excitation frequency ranging from 750 Hz to 10 kHz with an accuracy of 2.35%. The overall power consumption of the system was 140.4 mW in normal operating mode and 81 µW in sleep mode. The proper development of the isolated bacteria was confirmed through DNA sequencing, indicating that bacteria thrive in the EcoChip's culture wells while the growing conditions are successfully gathered and stored.

A Proposal for a Forest Digital Twin Framework and Its Perspectives

“…• roots growth and dynamics of the tree: expensive, limited to white-light imaging, and often requiring human intervention [31]; • soil nutrients: reduced commercial availability [32]; • soil microbiology: under development for specific use cases [33].…”

Portable impedance-sensing device for microorganism characterization in the field

“…Market-available impedance analyzers can be found in portable formats, but their prices are prohibitive for large scale deployment. As an alternative to these instruments, low-power low-cost integrated chips exist with impedance analyzer capabilities [30][31][32][33] . These chips can be used as all-in-one-package solutions for low-cost impedance analysis, but are not as versatile as benchtop instruments and their excitation frequency often proves insufficient for microorganism characterization.…”

Unsupervised classification of voltammetric data beyond principal component analysis

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