A Portable Integrated Electrochemical Sensing System for On‐Site Nitrite Detection in Food

Abstract

Ensuring an appropriate nitrite level in food is essential to keep the body healthy. However, it still remains a huge challenge to offer a portable and low‐cost on‐site food nitrite analysis without any expensive equipment. Herein, a portable integrated electrochemical sensing system (IESS) is developed to achieve rapid on‐site nitrite detection in food, which is composed of a low‐cost disposable microfluidic electrochemical patch for few‐shot nitrite detection, and a reusable smartphone‐assisted electronic device based on self‐designed circuit board for signal processing and wireless transmission. The electrochemical patch based on MXene‐Ti3C2Tx/multiwalled carbon nanotubes‐cyanocobalamin (MXene/MWCNTs‐VB12)‐modified working electrode achieves high sensitivity of 10.533 µA mm−1 and low nitrite detection limit of 4.22 µm owing to strong electron transfer ability of hybrid MXene/MWCNTs conductive matrix and high nitrite selectivity of VB12 bionic enzyme‐based ion‐selective layer. Moreover, the portable IESS can rapidly collect pending testing samples through a microfluidic electrochemical patch within 1.0 s to conduct immediate nitrite analysis, and then wirelessly transmit data from a signal‐processing electronic device to a smartphone via Bluetooth module. Consequently, this proposed portable IESS demonstrates rapid on‐site nitrite analysis and wireless data transmission within one palm‐sized electronic device, which would pave a new avenue in food safety and personal bespoke therapy.

Ag-CeO2 Based on Electrochemical Sensor for High-Efficient On-Site Detection of Nitrite in Aquaculture Water and Beverages

“…In recent years, colorimetry sensors [ 5 ], fluorescence sensors [ 6 ], surface-enhanced Raman scattering sensors [ 7 ], microfluidic sensors [ 8 , 9 ], and electrochemical sensors have been extensively developed for rapid onsite analysis and portability [ 10 ]. Colorimetry sensors and spectroscopy sensors, including UV–vis spectroscopy and fluorescence spectroscopy, often have interference from substrates in samples and non-specific adsorption, limiting their accuracy in nitrite analysis.…”