Marco Iammarino, Giovanna Berardi, Marco Langianese, Valeria Nardelli

Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Via Manfredonia, 20, Foggia, Italy

The evaporative light scattering detector (ELSD) allows a detection based on the irradiation of light scattered microparticles of target compounds which remain after evaporation of mobile phase, particularly useful to detect components with no UV absorption. Given its peculiarities, ELSD represents a good alternative to traditional approaches. In food safety, during the last years, much attention has been paid to food sweeteners, since some toxic effects have been demonstrated. These additives are characterised by different chemical structures so that their simultaneous determination, using the same analytical detection, is difficult. In this regard, the use of ELSD can be effective to solve the issue. 

In this study, an analytical method for the determination of 8 sweeteners, namely Acesulfame-K, Cyclamate, Aspartame, Sucralose, Dulcin, Alitame, Neohesperidine dihydrochalcone and Neotame, based on UPLC/ELSD, has been tested on both solid and liquid foods. Sample preparation consists of an ultrasonic extraction using a pH 4.5 buffer composed of formic acid and triethylamine, and SPE. The chromatographic separation was accomplished by using a Nucleodur® C18 Pyramid column and a gradient elution (Figure 1) [1]. 

The validation parameters were satisfactory. The LOQs were all lower than 10 mg/kg. Method selectivity was ascertained by verifying the absence of interfering peaks. Method linearity was assessed obtaining R2 values higher than 0.999. Method accuracy was demonstrated by spiking tests with recovery percentages in the range 72.3% – 91.7% and CV% values lower than 10%. Method applicability for official control of food and beverages was also assured by completing a Proficiency Test Round, and by calculating the measurement uncertainty, lower than 15% for all compounds.

Acknowledgements: The participation to the “Scienza delle Separazioni 2024” meeting was possible thanks to the Italian Ministry of Health (Rome, Italy) who financed the research project code IZSPB 04/22 RC.

Keywords: ELSD, food safety, sweeteners, validation.

References

1. Wasik J, McCourt J, et al., J. Chrom. A, 1157 (2007), pag. 187-196. DOI: 10.1016/j.chroma.2007.04.068.