In this paper (purchase required) a reversed-phase thin-layer chromatography (RP-TLC) method was developed to quantify the flavour enhancer monosodium glutamate (E-621) in various food samples following ultrasound-assisted extraction.
RP-TLC layers were precoated with RP-18 modified silica gel 60 F254s. The mobile phase was ethanol‒water‒isopropanol (5:2.5:2.5, V/V). The method used densitometric detection at 570 nm with an RF value of 0.57.
The authors report that Monosodium glutamate (MSG) showed linearity in 500–1500 ng/spot range. RP-TLC separation was optimized, and the most influential and interacting parameters were identified using central composite design. Validation study was performed as per the International Council for Harmonisation (ICH) recommendations, which demonstrated all the parameters are within acceptable limits. MSG showed recovery of 93.12–101.42% among various food samples.
This test method was specifically designed to be sustainable and “green”, both in the extraction technology and the solvents used. Its development used Analytical Quality by Design (AQbD) methodology, and various sustainability metrics are reported as favourable.
The authors conclude that the method provides a fast and environmentally friendly alternative to traditional procedures used to analyse MSG in foods.
