Second-Generation Organic Nanozyme for Effective Detection of Agricultural Herbicides

Abstract

Inorganic nanozyme-based biosensors are extensively used for detecting toxic molecules, offering an alternative to fragile enzyme-based sensors and conventional analytic tools. However, inorganic materials can pose environmental risks due to toxicity and low sustainability properties, which may lead to pollution after intended use. To address these limitations, sustainable organic nanozyme-based sensing platforms are essential for overcoming sustainable issues and effectively detecting toxic agrichemicals. In this study, a second-generation, sustainable organic compound-based nanozyme (EU nanozyme) is introduced, which exhibits peroxidase-like catalytic activity. The nanozyme is synthesized using a modified, self-assembled fabrication procedure that produced a homogenous, spherical nanozyme within 2 h and incorporated a partially mimicked cofactor of the natural peroxidase. This EU nanozyme exhibits decent kinetic profiles (Km = 0.006 mm, H₂O₂), along with degradability and biocompatibility, making it suitable for direct implementation in agricultural environments and highlighting its sustainability. The EU nanozyme-based colorimetric sensing platform effectively detects toxic herbicides (e.g., Atrazine), with decent analytic sensitivity with a Limit of Detection (LOD) of 0.231 pg mL⁻¹, strong analytic selectivity among more than six relative agrichemicals/and other pesticides, and specificity in corn samples with a LOD of 0.394 µgmL⁻¹, within a short detection time of up to 3 min. It is envisioned that this platform may offer promising advancements in enhancing agricultural safety.