116 How Sodiation Infuences the Sucralose Behavior under Electrospray Ionization Mass Spectrometry Paulo de Tarso Ferreira Sales 1 , Katia Maria de Souza 2 , Alyne Gonçalves Bezerra 1 , Satu Anneli Ojala 3 , Sérgio Botelho de Oliveira 2 , Pierre Alexandre dos Santos 1 , Maria Teresa Freitas Bara 3 * 1 Universidade Federal de Goiás, Praça bloco B – R. 240, 406 – Setor Leste Universitário, CEP: 74605-170, Goiânia, GO, Brazil 2 Instituto Federal de Goiás, R. 75, nº 46 – Centro, CEP: 74055-110, Goiânia, GO, Brazil 3 Oulun Yliopisto, Faculty of Technology, Environmental and Chemical Engineering, University of Oulu, FI-90014, P.O. Box 4300, Oulu, Finland TECHNICAL NOTE Brazilian Journal of Analytical Chemistry 2022, Volume 9, Issue 36, pp 116–123 doi: 10.30744/brjac.2179-3425.TN-99-2021 Submitted 10 September 2021, Resubmitted 26 October 2021, Accepted 4 January 2022, Available online 7 March 2022. Cite: Sales, P. T. F.; de Souza, K. M.; Bezerra, A. G.; Ojala, S. A.; de Oliveira, S. B.; dos Santos, P. A. Bara, M. T. F. How Sodiation Infuences the Sucralose Behavior under Electrospray Ionization Mass Spectrometry. Braz. J. Anal. Chem. 2022, 9 (36), pp 116–123. http://dx.doi.org/10.30744/brjac.2179-3425.TN-99-2021 Nowadays, the detection of sucralose sodium adduct under electrospray ionization in mass spectrometry analysis is a common analysis method, but its high chemical stability is not fully understood. In this work, we use quantum chemistry calculations and mass spectrometry data to understand why sodiated sucralose presents this behavior in mass spectrometry conditions. The potential energy and the position of sodium ions were evaluated using diferent basis sets in order to comprehend the importance of sodiation in sucralose properties. Quantum- chemical calculations show higher reliability to explain the behavior of sucralose sodium adduct under mass spectrometry conditions, especially when its molecular geometry and potential energies are evaluated. Keywords: DFT, Fukui functions, basis set, molecular geometry, potential energy. INTRODUCTION Sucralose (C 12 H 19 Cl 3 O 8 – CAS 56038-13-2) is a synthetic organochlorine sweetener, sweeter than sucrose. Due to its wide use, and its environmental spreading, a higher sensitivity quantifcation method of sucralose sodium adduct was already reported, 1 that showed that it is interesting to evaluate sodiated compounds from diferent matrices in mass spectrometry (MS) studies. Nowadays, the use of MS for detection and quantitative analysis has been widely reported, 2–4 and today MS represents a conventional method for detecting several compounds. Although the detection of sodium adducts are reported for many pharmaceutical and organic compounds, 5–8 in studies using electrospray ionization (ESI) in mass