Phytoelectronic soil sensing
Lead Research Organisation:
University of Cambridge
Department Name: Engineering
Abstract
The research objective of this project is to accurately, densely and remotely measure the state of the soil using plants as in situ chemical laboratories. The sap of these "interrogator plants" will be analyzed by implanted bioelectronic sensors and remotely communicated by low-power radio interrogation. This approach will avoid the complexity of sensing the soil directly by instead detecting the chemical response of vascular fluids to chemical and biological changes of the soil around the roots. These fluids, which are transported by the woody xylem tissues, are under negative pressure and thus typically difficult to access. The project will thus investigate a number of regeneration techniques for surgically implanted, small sensors such that these sensors become grafted into the xylem tissue, much like fruit trees are currently grafted. The entire small sensor including implanted electronics and regenerative coating will be screen-printed for very low cost. Screen printing recipes and other enabling techniques will be shared with the public through the Open Science Framework. Public use of these results will be further fostered by funded kits distributed to teams through the international BioMaker and OpenPlant programs.
Planned Impact
Disadvantaged Colorado high school students will explore the integration of phytoelectronic sensors and Arduinos via massively online courseware created by the PI. Undergraduate Capstone students will contribute to the research by developing the custom RFID interrogator. Graduates will gain international research training by continuing the established exchange of students between the US and UK PI labs. Participation of under-represented groups will be increased by REUs of female physics students from a liberal arts school and the CU GoldShirt program for motivated and under-represented students.
Global dissemination of program results such as DIY screen-printing processes for phytoelectronic sensors will occur through the Open Science Framework. Public use of these results will be fostered by funded kits distributed to teams through the international BioMaker and OpenPlant programs. Researchers at the Forestry and Agricultural Biotechnology Institute, Pretoria will apply project results to permanent soil monitoring in woody plants. This project is expected to be the first of many promoted through a newly established Phytoelectronics Working Group with BioMaker partners at the Kumasi Hive in Ghana, Mansoura University, Egypt; University of Pretoria, South Africa; Bahir Dar University, Ethiopia and University of Adelaide, Australia.
Global dissemination of program results such as DIY screen-printing processes for phytoelectronic sensors will occur through the Open Science Framework. Public use of these results will be fostered by funded kits distributed to teams through the international BioMaker and OpenPlant programs. Researchers at the Forestry and Agricultural Biotechnology Institute, Pretoria will apply project results to permanent soil monitoring in woody plants. This project is expected to be the first of many promoted through a newly established Phytoelectronics Working Group with BioMaker partners at the Kumasi Hive in Ghana, Mansoura University, Egypt; University of Pretoria, South Africa; Bahir Dar University, Ethiopia and University of Adelaide, Australia.
Publications
Bidinger S
(2022)
Highly stable PEDOT:PSS electrochemical transistors
Ruiz-Gonzalez A
(2023)
A Simple Reversed Iontophoresis-Based Sensor to Enable In Vivo Multiplexed Measurement of Plant Biomarkers Using Screen-Printed Electrodes.
in Sensors (Basel, Switzerland)
Bidinger SL
(2022)
Pulsed transistor operation enables miniaturization of electrochemical aptamer-based sensors.
in Science advances
Bihar E
(2023)
Self-healable stretchable printed electronic cryogels for in-vivo plant monitoring
in npj Flexible Electronics
Zedler M
(2023)
Paper-Based Multiplex Sensors for the Optical Detection of Plant Stress.
in Micromachines
Ruiz-Gonzalez A
(2022)
In Vivo Sensing of pH in Tomato Plants Using a Low-Cost and Open-Source Device for Precision Agriculture.
in Biosensors
Bidinger S
(2022)
Highly stable PEDOT:PSS electrochemical transistors
in Applied Physics Letters
Han S
(2021)
Integration of Organic Electrochemical Transistors with Implantable Probes
in Advanced Materials Technologies
Han S
(2020)
Microfabricated Ion-Selective Transistors with Fast and Super-Nernstian Response.
in Advanced materials (Deerfield Beach, Fla.)
Strand E
(2021)
Printed Organic Electrochemical Transistors for Detecting Nutrients in Whole Plant Sap
in Advanced Electronic Materials
Description | Transistor-based ion sensors: The best-performing ones rely on a liquid electrolyte as an internal ion reservoir between the ion-selective membrane and the channel. This liquid reservoir makes sensor miniaturization difficult and leads to devices that are bulky and have limited mechanical flexibility, which is holding back the development of high-performance implantable ion sensors. We made microfabricated ion-selective organic electrochemical transistors (OECTs), in which a thin polyelectrolyte film with mobile sodium ions replaces the liquid reservoir. These devices are capable of selective detection of various ions with a fast response time (˜1 s), a super-Nernstian sensitivity (85 mV dec-1), and a high current sensitivity (224 µA dec-1), comparing favourably to other ion sensors based on traditional and emerging materials. Furthermore, the ion-selective OECTs are stable with highly reproducible sensitivity even after 5 months. These characteristics paved the way for applications in sampling the sap in plants. Implantable transistors: For implantable applications, OECTs need to be integrated with narrow shuttles, where the scarcity of real estate creates two major issues: First, the small footprint of gate electrodes results into inefficient gating and low transconductance, and this decreases the utility of OECT as amplifiers. Second, the inevitable voltage drop along the narrow interconnects needs to be accounted for appropriately to optimize device operation. We made OECTs where electropolymerisation of a conducting polymer film on a small gate electrode increased capacitance and led to high transconductance. We also developed a methodology to account for the electrical characteristics of the OECTs with appropriate correction for the voltage drop along the interconnects. This work facilitated the development of efficient OECT-based implantable ion sensors for plants. Detecting potassium concentration in whole plant sap: Together with the Colorado team, we developed printed ion-selective OECTs that can be used for high-throughput, low-cost plant health monitoring. Furthermore, we demonstrated real-time detection of potassium concentrations in whole plant sap using the developed sensors. In vivo potassium recording in tomato xylem: We have successfully implanted potassium sensors in tomato xylem and measured the potassium concentration in real time, without damage to sensors. The measured value was around 20 mM which is within the range of the potassium concentration found in the literature. This work will be soon submitted for publication along with additional experimental results. Development of a novel implantation technique: Previously, we used the insertion method which was designed for implanting devices into ultrasoft tissues like brain. However, as plant stems are quite rigid, we needed to make a pre-incision with a scalpel or thick needle, which inevitably led to significant damage to stem tissue. Furthermore, the large incision made the sensor contact with xylem loose, which could give false read-outs of ion concentrations. To overcome these issues, we developed a new implantation protocol using a device folded around a 3D-printed shuttle that is thin but rigid - The device is inserted with the shuttle and the shuttle is removed, only leaving the device within the xylem. In addition, the project included a major effort to democratise access to new tools for measurements of plant-soil interactions. This has been based on the Biomaker initiative (https://www.biomaker.org), founded in the Haseloff lab. With support from the SitS programme, we have developed an improved multistage training programme, employing low-cost microcontroller hardware that can be used for field and laboratory work - that is Arduino-compatible, battery-powered, with long-range, low-power wireless communications (LoRaWAN) and is no-code programmable. We have used this platform to develop and share new training materials and workshops (https://www.biomaker.org/training-programme) and to develop pioneer projects for soil sensing. |
Exploitation Route | Ion sensors are being used in many sectors and the fact that we have achieved in making them small and highly performant may lead to applications beyond the sector targeted in this grant. For example, they can be used in implantable formats to study the brain. |
Sectors | Aerospace, Defence and Marine,Agriculture, Food and Drink,Electronics,Environment,Healthcare,Manufacturing, including Industrial Biotechology |
Description | Scion Research |
Organisation | Scion |
Country | New Zealand |
Sector | Public |
PI Contribution | We started a collaboration with SCION (Crown Research Institute of Forestry in New Zealand) who are interested in using our sensors to monitor the health of forests in New Zealand. So far the collaboration has yielded a travel grant for SCION to send people to Cambridge and invite Prof. Malliaras to visit SCION. The visit took place in February 2023. Two Scion scientists visited Cambridge in 2022. |
Collaborator Contribution | The partners will help us expand the use of our sensors to monitoring the health of forests. Preliminary results show proof of concept. |
Impact | So far, scientific visits between SCION and Cambridge. SCION has raised funds for this project from the government of NZ and will contract some work at Cambridge. We are planning the submission of an EU project in 2023. |
Start Year | 2021 |
Description | Biomaker Training Workshop |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Postgraduate students |
Results and Impact | Series of Training Workshops for no-code programming and assembly of scientific instrumentation as documented at https://www.biomaker.org. Follow-on participation in open source projects. |
Year(s) Of Engagement Activity | 2022,2023 |
URL | https://www.biomaker.org |
Description | CDT-Sumitomo online workshop |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Industry/Business |
Results and Impact | UK-Japan online workshop to discuss advanced research topics and possible translation to applications |
Year(s) Of Engagement Activity | 2021 |
Description | Creation and running of online training workshops for Biomaker |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | In response to the COVID lockdown Stephanie Norwood and I, as organisers of the Biomaker initiative, introduced more easily accessible hardware resources and created novel training materials for online teaching of no-code programming techniques for biologists lacking in formal programming skills. (https://www.biomaker.org/nocode-programming-for-biology-handbook). We have distributed around 200 hardware kits and run a series of online workshops via Zoom. |
Year(s) Of Engagement Activity | 2020,2021 |
URL | https://www.biomaker.org |
Description | Invited presentation at CRI, Paris |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Invited presentation: Open Tools for Engineering Biology |
Year(s) Of Engagement Activity | 2021 |
Description | Invited presentation at online Hitachi-sponsored workshop in Cambridge |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Industry/Business |
Results and Impact | UK-Japan online workshop to discuss advanced research projects and possible industrial translation. |
Year(s) Of Engagement Activity | 2021 |
Description | Invited talks at the MRS Spring Meeting, May 8-13, 2022 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Delivered two invited talks and several contributed (by group members) to a large and interdisciplinary audience interested in applications of novel materials |
Year(s) Of Engagement Activity | 2022 |
URL | https://www.mrs.org/meetings-events/spring-meetings-exhibits/past-spring-meetings/2022-mrs-spring-me... |
Description | Keynote presentation at Hellenic Conference on Solid-State Physics and Materials Science |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Gave the keynote presentation at national conference |
Year(s) Of Engagement Activity | 2022 |
URL | https://fsk36.materials.uoc.gr/ |
Description | Keynote presentation: "Hybrid and 3D Printed Bioelectronics" |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Third sector organisations |
Results and Impact | 11th International Conference & Exhibition on Green Flexible & Printed Electronics Industry Held Oct 22, 2021 in Athens, Greece |
Year(s) Of Engagement Activity | 2021 |
Description | No-code programming online workshop |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Organised and delivered an online workshop to provide training for non-programmers in the use of microcontrollers for scientific applications. Distributed standard hardware for the training sessions ahead of the workshop. Dec 8th and 9th 2021. |
Year(s) Of Engagement Activity | 2021 |
URL | https://www.biomaker.org |
Description | No-code programming workshop, University of Veracruz, Mexico |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Online workshop, co-sponsored with Prof. Mario Arteaga, University of Veracruz, Mexico - introducing research students to no-code programming for scientific instrumentation. |
Year(s) Of Engagement Activity | 2022 |
URL | https://www.biomaker.org |
Description | Production and distribution of Biomaker training materials for online training. |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Provision of free online training materials to complement a starter pack is based on the Grove All-in-One Beginner Kit for Arduino. We have developed a visual guide, which provides step-by-step instructions of how to control the board using the XOD visual programming environment. The first lessons are available for download now. XOD tutorial code is also available to accompany this guide. In addition, training videos can be viewed online. |
Year(s) Of Engagement Activity | 2020,2021 |
URL | https://www.biomaker.org/nocode-programming-for-biology-handbook |
Description | Public Seminar on Bioelectronic Medicine, University of Linkoping, Sweden. |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Public seminar on the occasion of award of honorary doctorate, reaching current members, alumni and steakholders of Linkoping University. |
Year(s) Of Engagement Activity | 2022 |
Description | Visit at SCION - NZ Institute of Forestry |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | I visited SCION and provided opportunities for Scion staff to connect with my group on research projects and engages during presentation that highlighted our areas of expertise. |
Year(s) Of Engagement Activity | 2023 |
URL | https://www.scionresearch.com/about-us/news-and-events/news/2023-news-and-media-releases/visiting-pr... |