Articles
Publication Date: 2025
Microchemical Journal (0026265X)219
The quantification of glyphosate in aqueous systems is vital for environmental preservation and public health safety, enabling the tracking of agricultural runoff and supporting data-driven regulatory measures. This research details the development and construction of an electrode modified with cobalt oxide nanoparticles (CoOx) to serve as a high-sensitivity platform for the electrochemical sensing of glyphosate. Synthesis of the CoOx nanoparticles was followed by their electrochemical deposition onto a glassy carbon (GC) substrate through cyclic voltammetry under predetermined optimal parameters. The structural and electrochemical characteristics of the resulting modified electrodes were thoroughly analyzed using a suite of analytical methods: field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Electrochemical assessments revealed that the electrodes possessed significantly enhanced activity, which was directly attributed to the incorporated nanoparticles. Crucially, both CV and EIS analyses verified a potent affinity and interaction between the glyphosate molecules and the CoOx nanomaterial. EIS measurements further established a linear correlation between the charge transfer resistance and glyphosate concentrations spanning from 0.15 to 0.9 μM, thereby confirming the sensor's effective detection mechanism. The constructed biosensor demonstrated a sensitivity of 6.5 μA and a linear response across the 0.15–0.9 μM glyphosate range, achieving a calculated detection limit (LOD) of 0.8 μM. Collectively, these results underscore the efficacy of the CoOx-based electrode as a promising and robust tool for monitoring glyphosate contamination in water, thereby aiding initiatives aimed at ensuring water quality and safeguarding community health. © 2025
Publication Date: 2024
ACS Applied Nano Materials (25740970)7(16)pp. 19481-19492
Nanofluidic systems due to their unique transport properties play a crucial role in a lot of applications ranging from water desalination to sensors. Over the past few years, considering the simple structure of two-dimensional materials, significant efforts have been devoted to designing synthetic membranes for ion transport. However, expensive fabrication methods such as lithography techniques and some shortcomings such as scale-up difficulty, low pore density, poor mechanical stability, and biocompatibility limit their practical application. Herein, we demonstrate a scalable hierarchically porous membrane with three-dimensional (3D) interconnected nanochannels which is based on the silk fibroin (SF) fiber biomass and modifying the nanofluidic channels by in situ growth of zeolitic imidazolate framework-67 (ZIF-67) nanoparticles on the fiber surfaces. The ZIF-67/SF membrane with 400 μm thickness is a 3D interconnected network with a large positively charged surface area (54 m2 g-1) containing 1-5 nm pores estimated from density functional theory modeling. Surface-charge-governed ion transport through the nanofluidic channels of the ZIF-67/SF membrane is systematically explored, and characteristic higher-than-bulk ion conductivity was observed at low concentrations (≤10-3 M) of monovalent electrolytes (KCl, NaCl, NaOH, and HCl). Moreover, the ZIF-67/SF is stable and fully functional at elevated temperatures up to 60 °C and maintains its structural and operational properties under acidic and basic conditions. © 2024 American Chemical Society.
