Work

Porous microneedle-based electrochemical sensor for the in vivo detection of metals in Alliaria petiolata at an urban industrial wasteland

Year: 2026

Type: article

Abstract: The site under study, located in Vieux-Charmont, France, is a former industrial and household waste landfill contaminated with several toxic elements, notably zinc (Zn), lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), nickel (Ni), chromium (Cr) and mercury (Hg). These metals are non-biodegradable and can pose a risk to the environment and human health. The plant Alliaria petiolata grows readily in contaminated areas of this site and is capable of accumulating certain heavy metals. It can therefore serve as a pollution bioindicator and potentially be used for phytoremediation. To measure the metals present in Alliaria petiolata leaves, a low-cost system consisting of a porous polymeric microneedle array — fabricated via molding — attached to a commercial screen-printed carbon electrode was used. The microneedles penetrate the leaf slightly, allowing for the extraction of the apoplast-enriched leaf fluid, where metal ions can be detected. In Alliaria petiolata leaves from contaminated areas, the differential pulse anodic stripping voltammetry (DPASV) electrochemical method enabled the detection and quantification of three metals: cadmium, lead, and copper. The concentrations measured in the apoplast-enriched leaf fluid were approximately: Cd: 0.60 mg/L; Pb: 2.54 mg/L; Cu: 1.71 mg/L. The same order of concentrations (lead > copper > cadmium) was obtained by analyzing dried plant material using ICP-AES.

Source: Sensing and Bio-Sensing Research

DOI: 10.1016/j.sbsr.2026.101088