Simultaneous Determination of Preservatives, Artificial Sweeteners, and Synthetic Dyes in Kimchi by Ultra-Performance Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (UPLC-ESI-MS/MS)

A homogeneous binary matrix assisted laser desorption/ionization time-of-flight mass spectrometry assay for determination of artificial sweeteners in beverages

Artificial sweeteners have been widely used as additives in various beverages. Due to the safety risks associated with artificial sweeteners, it is essential to develop a simple, rapid, and high-throughput method for the analysis of artificial sweeteners. Here, we report a homogeneous binary matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) assay for the simultaneous analysis of sweeteners including aspartame (ASP), neotame (NEO), and advantame (ADV) with a simple dilution step. The combination of nanodiamonds with 2,5-dihydroxybenzoic acid effectively improved the signal response of sweeteners, decreased the background noise, and improved the "spot-to-spot" repeatability. After the optimization, the method exhibits low limits of detection (ASP: 20 nΜ; NEO: 10 nΜ; ADV: 5 nΜ), good linearity (r > 0.995), satisfactory accuracy (96.2-103.0%), and lower RSDs (1.5-5.8%). Finally, the target sweeteners in 17 soft beverages were successfully determined with this method, showing the potential for the routine analysis of artificial sweeteners.

Development, validation and application of multi-class methods for the analysis of food additives by liquid chromatography coupled to tandem mass spectrometry

Food additives are used in numerous food products and are characterised by various physicochemical properties. In European member states, their use in food is regulated by the European Union. This work aimed to develop an accurate and high-throughput analytical method enabling the simultaneous determination of additives from different functional classes to facilitate controls and generate occurrence data for exposure assessments. The QuEChERS principle was applied due to its ease of implementation and flexibility to adjust to various food matrices. However, very polar substances could not be extracted with sufficient recoveries. Consequently, an alternative basic methanol sample-preparation methodology was developed. After sample preparation, the obtained extracts were analysed using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Overall, the developed methodology allowed the quantification of 27 additives from the functional classes of colours, sweeteners, preservatives, and antioxidants in various foods (e.g. beverages, dairies, processed meals). The methods were also validated in terms of selectivity, linearity, matrix effect, limit of quantification, accuracy, repeatability, and intra-laboratory reproducibility. Finally, the methods were successfully applied to eighty-four actual samples. All additives were found below authorised levels. However, irregularities were spotted in labelling.

Box-Behnken Design-Desirability Function Approach in Optimization of HPLC Method for Simultaneous Determination of Ibuprofen Along with Additives in Syrup Formulation

BACKGROUND

The advantages of simultaneous analyses are a decrease in analysis time and a more economical use of solvents and reagents. It is desirable that HPLC analyses possess both short term and good resolution.

OBJECTIVE

The aim of the current study is to develop an HPLC method for the simultaneous determination of ibuprofen, sodium benzoate, methyl paraben and propyl paraben as preservatives, and sunset yellow as a colorant, in syrup formulation.

METHOD

To optimize chromatographic separation conditions, multi-response optimization using the Derringer's desirability function was employed for the development of a rapid and efficient HPLC method. The ranges of independent variables used for the optimization process were 50-60% (v/v) for acetonitrile, 5.0-7.0 for pH, and 1.0-2.0 mL/min for flow rate of the mobile phase. The effects of these variables on the output responses, such as critical resolution between sunset yellow and sodium benzoate and retention time of the last peak indicating analysis time of the method, were evaluated by statistical experimental design.

RESULTS

Optimum conditions fixed for the simultaneous analyses were acetonitrile:phosphate buffer (60:40, v/v), pH 5.0, and a flow rate of 1.8 mL/min. The eluate was monitored using a photo diode detector set at 220 nm. Total chromatographic analysis time was approximately 3 min.

CONCLUSIONS

The developed method validated as per International Conference on Harmonization guidelines was successfully applied for the determination of five compounds in their pharmaceutical formulation.

HIGHLIGHTS

This efficient method has isocratic elution system and can be used for routine analyses of these compounds in similar pharmaceutical products.