Nanocrystalline graphite-patterned silicon substrates for molecularly imprinted biopolymer-based electrochemical detection of glyphosate

In this study, we present the fabrication and characterization of a miniaturized, single-chip electrochemical sensor implemented on a silicon/silicon dioxide platform. The device incorporates a nanocrystalline graphite (NCG) working electrode and gold reference and counter electrodes, all monolithically integrated on the same substrate. This configuration provides a compact and reliable sensing architecture, combining the electrochemical advantages of carbon with the precision and reproducibility of microfabrication. A molecularly imprinted biopolymer (MIP) layer for glyphosate (GLY) detection was subsequently formed by electrodepositing chitosan (CS) in the presence of the target analyte, directly onto the NCG surface. The resulting sensor exhibited high sensitivity and selectivity, allowing indirect detection of GLY at concentrations as low as 0.015 ppb. Validation tests demonstrated excellent recovery rates in spiked water samples, highlighting the sensor’s potential for environmental monitoring applications. This integrated platform offers a promising approach for the sensitive, portable, and cost-effective detection of GLY residues.