SAP DEVICE. AUTONOMOUS MEASUREMENT IN COMPLEX SAMPLES AND FOR THE AUTONOMOUS EXTRACTION OF A LIQUID SAMPLE

A novel wearable immunosensor device based on an electrochemical lateral flow assay (eLF) that includes an autonomous microsampling from living plants for minimally invasive sap in situ extraction and biochemical detection of stress hormones (abscisic acid, ABA). The sap device collects, processes and analyzes plant sap with low sample volume (<10 µL) and short assay time (< 10min) using wearable detection based on immunosensing for the first time in ABA . Validation in drought-stressed cucumber plants demonstrated 78% and 71% sensitivity and specificity, respectively. It confirms its ability to detect with high accuracy (77%) very little water stress in situ in living plants, intentionally adjusted to mimic early-stage stress. It has been also validated in tomato plants for air quality monitoring. These facts constitute the innovative features of the system, in situ real-time bio-based detection of stress-hormones by a plant wearable device capable of being adapted to other plants or biomarkers, for any kind of molecule in sap.