Paper-Based Electrochemical Aptasensor Chip for Ultrasensitive Glyphosate Detection Enabled by MXene-Au and Au@NiCo LDH Nanozyme Amplification.

As one of the world's most widely used herbicides, glyphosate (Gly) poses considerable ecological and human health risks due to its environmental persistence and capacity to bioaccumulate through food webs in both terrestrial and aquatic ecosystems. Thus, developing analytical methods for Gly is critical for environmental monitoring, food safety, and public health protection. In this study, we combine electrochemical detection with paper-based microfluidics to develop a novel rotary paper-based aptasensor for highly selective and sensitive Gly quantification in environmental samples. Thiolated capture DNA (cDNA) is immobilized on the electrode surface via stable Au-S bonds, forming a well-defined recognition interface. An apt-Au@NiCo LDH with intrinsic peroxidase-like activity is then anchored via complementary base pairing. Gly binding to its specific aptamer triggers measurable electrochemical signal changes, enabling precise recognition and quantification. The sensor achieves a wide linear range of 0.1 pg/mL-10 ng/mL, and the limit of detection (LOD) is 0.05 pg/mL. This work provides a novel, efficient, economical, and practical solution for on-site, rapid, and ultrasensitive Gly detection in environmental samples. The platform shows strong promise for real-world applications.