Development and validation of a portable paper-based low-cost electrochemical sensor for the detection of monosodium L-glutamate in food

Abstract

Monosodium L-glutamate (MSG) is a common ingredient that is added to food to enhance its taste. However, due to the negative perception of consumers towards MSG, most food manufacturers do not inform customers if MSG has been added to food. This work describes the development and validation of a low-cost electrochemical microfluidic paper-based analytical device (µPAD) for the rapid, on-site detection of MSG in food samples. This device is a portable, low-cost, one-time sensor that can be used on the field even directly without sample preparation. This would greatly benefit groups of society such as Public Health Inspectors and individuals who regularly consume fast food. The µPAD was fabricated with a three-electrode system consisting of a working electrode modified with Co3O4 nanoparticles, a pseudo reference electrode, and a counter electrode. The device is tested using food samples spiked with MSG 5 g/L. The test results prove that the device can be used as a qualitative sensor to detect MSG in food with the limit of detection 0.82 g/L