A novel fast and simple quantification method for vitamins, complements and contaminants in milk infant formulas by LC-MS/MS

Importance of the topic

The precise quantification of vitamins, dietary supplements and trace contaminants in infant milk formulas is essential to guarantee nutritional quality, consumer safety and regulatory compliance. Rapid and accurate analysis of both fat-soluble and water-soluble compounds addresses manufacturing challenges and supports quality control in the infant nutrition industry.

Aims and study overview

This work introduces a unified LC-MS/MS strategy designed to measure over twenty target analytes—including vitamins A, D3, E, K1, B-complex vitamins, vitamin C, choline, inositol, taurine, L-carnitine, aflatoxin M1, chlorate, perchlorate and melamine—in commercial infant formula. The method simplifies sample processing by employing only two extraction procedures followed by a single ultra-high performance liquid chromatography separation.

Methodology and instrumentation

The analytical protocol consists of:

• Sample preparation: acidified methanol extraction for polar compounds; Biotage ABN SPE cleanup for fat-soluble vitamins.
• Chromatographic separation: reverse-phase column (150×2.1 mm, 3 µm) at 60 °C with a binary gradient of water and acetonitrile containing ammonium formate and formic acid; 400 µL/min flow rate; 14-minute total run time.
• Detection: Shimadzu Nexera X2 UHPLC coupled to LCMS-8050 triple quadrupole; fast polarity switching (5 ms), 555 MRM transitions per second; heating gas 10 L/min (air), drying gas 10 L/min (N2), nebulizing gas 2.5 L/min (N2).

Key results and discussion

Calibration curves exhibited excellent linearity (R² > 0.98) across the typical concentration ranges for all analytes, with signal-to-noise ratios ≥10 at the lower limit of quantification. Extraction recoveries for fat-soluble vitamins ranged from 83% to 107% with relative standard deviations below 8%. Water-soluble vitamins and other polar supplements achieved recoveries between 79% and 112% with RSDs under 9%. The method demonstrated robust performance for contaminants such as aflatoxin M1, chlorate, perchlorate and melamine at trace levels.

Benefits and practical applications

• Comprehensive coverage of diverse nutritional and safety markers in a single analytical run.
• High throughput: 14-minute cycle time enables rapid sample turnaround.
• Reduced method complexity with only two extraction steps.
• Reliable quantification suitable for routine quality control and regulatory verification.

Future trends and opportunities

Advancements may include integration of high-resolution mass spectrometry for non-targeted screening, automation of sample preparation workflows, and expansion of the analyte panel to emerging bioactives. Data-driven calibration and chemometric tools could further enhance throughput and predictive capability.

Conclusion

The presented LC-MS/MS approach provides a fast, simple and unified solution for quantifying vitamins, supplements and contaminants in infant milk formulas. Its high sensitivity, accuracy and streamlined workflow make it well suited for modern QC laboratories and regulatory environments.