Portable Electrochemical Nitrite Detection in Processed Meat Using Functionalized Multiwalled Carbon Nanotubes‐Modified Screen‐Printed Carbon Electrodes

Nitrite, an active compound in sodium nitrite (NaNO ₂ ) commonly used as a meat preservative, has been associated with various health risks upon overconsumption, highlighting the need for accurate detection techniques. This work presents the development of a portable and low‐cost electrochemical analytical device for nitrite detection, integrating a custom Arduino‐based potentiostat and a screen‐printed carbon electrode (SPCE) modified with functionalized multiwalled carbon nanotubes (f‐MWCNTs). The developed system is designed to be compact (~100 × 90 × 70 mm ³ ), cost‐effective (<30 USD), and user‐friendly, which allows for on‐site analysis. The sensor demonstrated a detection range of 1–50 mg L ⁻¹ , effectively covering the maximum residue limit of nitrite in processed meat. Additionally, the system exhibited a low limit of detection (LOD) and limit of quantification (LOQ) of 0.635 and 2.117 mg L ⁻¹ , respectively. Experimental examination of real processed meat samples confirmed the accuracy and reliability of the device, showing satisfactory agreement with the standard ion chromatography (IC) method. The results highlight the potential of this electrochemical approach as a superior alternative to conventional laboratory‐based methods, offering rapid, sensitive, and cost‐efficient nitrite monitoring in food safety applications.