Identification and Fragmentation of Sucralose Using Accurate-Mass Q-TOF LC/MS and Molecular Structure Correlator Software

Importance of the Topic

Sucralose is a widely used noncaloric sweetener that resists metabolism and accumulates in wastewater and surface water. Its environmental persistence and potential biological effects raise concerns about aquatic toxicity. Accurate and confident detection of sucralose in water is essential for environmental monitoring and public health assessments.

Objectives and Study Overview

This study evaluates high resolution Q-TOF LC/MS in both positive and negative electrospray ionization modes to identify and characterize sucralose in aqueous matrices. It also examines fragmentation pathways and applies molecular structure correlator software to support structural confirmation of fragment ions.

Methodology and Instrumentation

• Standard solutions prepared from a 1 000 µg/mL sucralose stock in water, diluted in methanol and water.
• Chromatography on an Agilent 1290 Infinity Binary LC System with ZORBAX Eclipse Plus C18 column (50 × 2.1 mm, 1.8 µm) using a gradient of acetonitrile and 0.1% formic acid in water at 0.4 mL/min and 25 °C.
• Mass spectrometry on an Agilent 6540 Accurate-Mass Q-TOF with Jet Stream ESI acquiring full scan (30–1 000 m/z) and targeted MS/MS in positive and negative modes.
• Data processed with Agilent MassHunter Workstation and Molecular Structure Correlator software for fragment assignment and pathway analysis.

Results and Discussion

• Negative ESI produced the deprotonated molecule [M−H]− at m/z 395.0073 and a characteristic HCl loss fragment at m/z 359.0306.
• Positive ESI yielded a strong sodium adduct [M+Na]+ at m/z 419.0038 and diagnostic saccharide fragments at m/z 221.0187 and 238.9848, reflecting sodium migration and ring cleavage.
• Signal intensity in positive mode was approximately twice that of negative mode, while negative mode offered slightly improved signal-to-noise due to reduced chemical background.
• Molecular Structure Correlator software reliably matched accurate mass MS/MS fragments to proposed structures, demonstrating its value for fragment verification.

Benefits and Practical Applications

High resolution Q-TOF LC/MS provides unambiguous identification of sucralose in environmental samples by distinguishing characteristic adducts and fragment ions with sub-ppm mass accuracy. This approach enhances trace analysis confidence and supports routine monitoring of emerging contaminants in water.

Future Trends and Potential Applications

Emerging trends include extending high resolution mass spectrometry to other persistent sweeteners and micropollutants, integrating advanced software for automated fragment annotation, and optimizing quantitative workflows for environmental surveillance and regulatory compliance.

Conclusion

Accurate-mass Q-TOF LC/MS combined with molecular structure correlator software offers a robust platform for the identification and structural confirmation of sucralose in water. Both positive and negative ESI modes yield diagnostic ions, with positive mode delivering higher signal intensity and negative mode reducing background interference. This methodology improves analytical confidence in monitoring environmental contaminants.

References

• A.K.E. Wiklund, M. Breitholtz, B.E. Bengtsson, M. Adolfsson-Erici Chemosphere 2012 86 50–55
• I. Ferrer, J.A. Zweigenbaum, E.M. Thurman Analytical Chemistry 2013 85 9581–9587