Fast Screening And Quantification Of Pesticide Residues In Baby Food Using GC Orbitrap MS Technology

Significance of the Topic

Ensuring the safety of baby food requires sensitive, high-throughput methods capable of detecting a broad range of pesticide residues at trace levels. Traditional GC-MS/MS methods rely on targeted acquisition and can miss unexpected or emerging contaminants. Full-scan high-resolution GC-Orbitrap MS addresses these limitations by providing comprehensive screening with excellent selectivity and quantification reliability.

Objectives and Study Overview

• Evaluate the performance of GC-Orbitrap MS for simultaneous screening and quantification of 132 pesticides in baby food matrices.
• Demonstrate compliance with SANCO guidelines for fast, high-throughput residue analysis.
• Compare sensitivity, mass accuracy, linearity and detection limits with a triple quadrupole GC-MS reference instrument.

Methodology and Instrumentation

Sample Preparation relies on a citrate-buffered QuEChERS protocol: 10 g of homogenized baby food is extracted with 10 mL acetonitrile, followed by addition of MgSO4, NaCl, disodium hydrogen citrate sesquihydrate and trisodium citrate dihydrate. Dispersive SPE clean-up uses MgSO4, C18, PSA and carbon to remove matrix interferences. Final extracts are spiked with pesticide standards at 0.5–200 ng/g.

Used Instrumentation

• Thermo Scientific Q Exactive GC Hybrid Quadrupole-Orbitrap MS
• Thermo Scientific Trace 1310 Gas Chromatograph
• TraceGOLD TG-5SILMS column, 30 m×0.25 mm×0.25 µm
• Programmed Temperature Vaporizing (PTV) cold splitless injector
• TraceFinder software for data acquisition and processing

Main Results and Discussion

• Chromatography achieved complete separation of first (dichlorvos, RT 4.46 min) and last (deltamethrin, RT 10.33 min) analytes within an 11-minute run.
• Orbitrap MS provided routine resolution of 60 000 FWHM (m/z 200), mass accuracy better than 0.4 ppm RMS across each peak, and full-scan sensitivity comparable to a TSQ 8000 Evo triple quadrupole.
• Instrumental Detection Limits (IDLs) for 91% of pesticides were below 2 ng/g, with linear dynamic ranges from 0.5 to 100 ng/g (R2 > 0.99, residuals < 25%).
• High scan speed ensured more than 15 data points per peak, enabling reliable quantification and confirmation via extracted ion chromatograms.

Practical Benefits and Applications

• Broad-scope screening in full-scan mode eliminates the need for compound-specific methods.
• High resolution suppresses isobaric interferences, improving confidence in complex matrices.
• Fast GC separation combined with robust mass accuracy supports high sample throughput in routine quality control.

Future Trends and Opportunities

Advances in HRMS instrumentation will drive further reductions in run time and detection limits. Integration of automated data-mining and suspect screening workflows can expand scope to unknown or non-targeted residues. Coupling GC-Orbitrap with ion mobility or complementing with LC-HRMS will enhance coverage for polar metabolites and degradation products.

Conclusion

GC-Orbitrap MS delivers full-scan, high-resolution performance that matches or exceeds targeted triple quadrupole methods for pesticide residue analysis in baby food. Its combination of speed, selectivity and sensitivity supports comprehensive monitoring and regulatory compliance in complex food matrices.

Reference

1. Commission Regulation (EU) No 396/2005 on maximum residue levels of pesticides in or on food and feed of plant and animal origin, Official Journal L 70, 16.3.2005.
2. SANCO/12571/2013 Guidance on analytical quality control and validation procedures for pesticide residues analysis in food and feed, 19.11.2013.
3. Commission Directive (EU) No 2003/13/EC amending Council Directive 96/EC on processed cereal-based and baby foods for infants and young children, 14.2.2003.
4. Cojocariu C., Hetmanski M., Silcock P., Fussell R.J. Three-Fold Increase in Productivity for Pesticide Residue Analysis in Baby Food Using Fast Triple Quadrupole GC-MS/MS. Thermo Scientific Application Note 10432, 2015.