An in vivo biosensing, biomimetic electrochemical transistor with applications in plant science and precision farming

Nicola Coppedè,Michela Janni,Marta Marmiroli,Salvatore Iannotta,Calogero Leandro Maida,Andrea Zappettini,Roberta Ruotolo,Manuele Bettelli,Marco Villani,Nelson Marmiroli,Francesco Gentile

doi:10.1038/s41598-017-16217-4

Abstract

The in vivo monitoring of key plant physiology parameters will be a key enabler of precision farming. Here, a biomimetic textile-based biosensor, which can be inserted directly into plant tissue is presented: the device is able to monitor, in vivo and in real time, variations in the solute content of the plant sap. The biosensor has no detectable effect on the plant’s morphology even after six weeks of continuous operation. The continuous monitoring of the sap electrolyte concentration in a growing tomato plant revealed a circadian pattern of variation. The biosensor has the potential to detect the signs of abiotic stress, and therefore might be exploited as a powerful tool to study plant physiology and to increase tomato growth sustainability. Also, it can continuously communicate the plant health status, thus potentially driving the whole farm management in the frame of smart agriculture.

Highlights

The in vivo, in loco and real-time detection of qualitative and quantitative changes to a plant’s physiological state is of great relevance for the success of precision farming, crop management and plant phenotyping
To understand how physiology and development are linked, and to visualize signaling processes in different organisms, two distinct classes of genetically encoded sensors have been developed and implemented, the first relies on the coupling of a ligand-sensitive receptor to a fluorescent protein, which is assayed by confocal microscopy; the second is based on electrochemical sensors combined with an enzymatic complex, which can be used to analyze liquid plant extracts[4,5,6]; among these, there are impedance sensors which measure variation in electrical resistance or capacitance
This paper has demonstrated that PEDOT:PSS based organic electrochemical transistors (OECT) have a high biocompatibility and may deeply interact with plant cellular system, even creating a transistor device inside their stem

Summary

Introduction

The in vivo, in loco and real-time detection of qualitative and quantitative changes to a plant’s physiological state is of great relevance for the success of precision farming, crop management and plant phenotyping. Receptors coupled to green fluorescent protein have been applied to monitor cellular concentrations of phytohormones[6,7,8,9], of reactive oxygen species[10], pH11, the calcium status[12] and the presence of specific pathogens[13] Sensors of this type have been applied to explore the role of specific molecules in a given physiological process[14,15,16,17,18,19], and have been used to reveal aspects of root cell metabolism[20,21]. This paper has demonstrated that PEDOT:PSS based organic electrochemical transistors (OECT) have a high biocompatibility and may deeply interact with plant cellular system, even creating a transistor device inside their stem

Methods

Results

Conclusion