I-Corps: Low-cost biochemical sensors to optimize agricultural inputs

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

The broader impact/commercial potential of this I-Corps project is the development of a wireless biochemical sensor nodes that will provide crop growers with real-time data on the chemical properties of their soil or hydroponic solution. Every year, 12 million hectares of arable land are lost due to soil degradation, erosion, and urban commercialization. At the same time, fertilizer prices have increased by 260% since November 2020. With land becoming more unusable, increasing fertilizer prices, and a changing climate, crop growers are struggling to produce sufficient yields reliably and are searching for potential solutions. The proposed wireless sensor nodes address these issues by providing crop growers, crop consultants, municipalities, regulators, and others with valuable information to improve efficiency, profitability, and resilience. A controlled environment agriculture (CEA) producer adopting the proposed technology may obtain an estimated 15-20% increase in net profit according to a techno-economic analysis. In addition, this technology may be expanded by creating sensors for other signals (such as pH, microbial/enzymatic activity, electrical conductivity, and/or temperature), fluids of interest (river water or groundwater), and by expanding to additional markets outside of industrial agriculture, such as consumer gardening, environmental monitoring, and/or chemical processing. This I-Corps project is based on the development of low-cost, biochemical sensors that measure concentrations of critical factors influencing plant growth, such as nitrate, nitrite, ammonium, phosphorus, and potassium (NPK). Currently, high-temperature silicon manufacturing methods are employed to produce biosensors with limited material compatibility. The proposed technology uses nanoparticle-based inks that contain polymer binders printed onto plastic substrates. In addition, scalable printing technologies are used to fabricate the ion-selective sensor array into a single replaceable sensor strip. The replaceable sensor strips are connected to an integrated circuit (IC) unit where a battery and an antenna for wireless data transfer are placed. These sensor nodes are programmed to take sensor measurements at regular intervals and wirelessly upload the data to the cloud. Previous results demonstrate that the sensors may accurately measure chemical concentrations in hydroponic solutions and several soil types. The nature of the sensors enables the collection of soil data at high spatial and temporal densities, which in turn enables an understanding of the relationships between agricultural inputs and soil health. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.