CHRONECT LC-GC CHRONECT Workstation PAH

Importance of Topic

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants formed during incomplete combustion and pyrolysis processes. Their presence in foodstuffs, whether from environmental deposition or cooking methods such as smoking and roasting, poses a significant health risk due to their carcinogenic potential. Regulatory bodies in Europe have set strict limits for PAH levels in various food matrices, driving the need for highly sensitive and reliable analytical methods.

Objectives and Study Overview

This product information describes the imPAHct method implemented on the CHRONECT Workstation PAH, a fully automated LC-LC-GC-MS/MS solution designed for routine analysis of PAHs according to European guidelines. The aim is to reduce sample handling time and increase throughput without compromising sensitivity, precision, or accuracy.

Used Methodology and Instrumentation

The imPAHct method combines a streamlined sample extraction and manual pre-treatment with an intelligent two-step liquid chromatography clean-up followed by GC-MS analysis. Key steps include:

• Simple extraction of solid or liquid food matrices
• Manual quick-treatment of the crude extract
• Two-dimensional LC clean-up (LC-LC) to remove matrix interferences
• Transfer to GC-MS for compound separation and detection

Instrumentation deployed in the CHRONECT Workstation PAH:

• CHRONECT Robotics platform (CTC PAL3 with 85 cm axis and CHRONOS software)
• Agilent 1260 Infinity II HPLC pump with UV detector and degasser
• Bruker EVOQ GC-TQ triple quadrupole mass spectrometer
• CHRONECT LC-GC interface module
• Dedicated data system for instrument control and data evaluation
• Complete set of accessories and consumables

Main Results and Discussion

The method delivers excellent analytical performance for the four EFSA-listed PAHs (benzo[a]pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene):

• LOD: 0.01–0.02 µg/kg for each PAH
• LOQ: <0.06 µg/kg for each PAH
• Repeatability: Relative standard deviation <10% across the full method
• Analysis time: 45 minutes per sample

Example chromatograms demonstrate effective separation and quantification, including a cocoa butter sample spiked at 0.04 µg/kg. Dual monitoring via the UV signal from HPLC clean-up and the GC-MS trace ensures robust matrix management and peak confirmation.

Benefits and Practical Applications

The imPAHct approach offers several advantages:

• Detection limits up to 100 times lower than required for strict matrices (e.g., infant formula)
• Elimination of solid-phase extraction cartridges thanks to LC-LC clean-up
• Extended instrument maintenance intervals and reduced downtime
• High sample throughput with minimal hands-on time
• Enhanced protection of the GC system from matrix contamination
• Uniform applicability to oils, vegetables, smoked products, and cosmetics

This fully integrated solution arrives pre-tested and ready for operation, ensuring quick deployment in routine laboratories.

Future Trends and Potential Applications

Ongoing developments may include:

• Extension of the method to additional PAH congeners and related contaminants
• Integration of high-resolution mass spectrometry for non-target screening
• Automation enhancements with machine-learning algorithms for real-time data interpretation
• Miniaturization and field-deployable variants for on-site monitoring

Conclusion

The imPAHct method on the CHRONECT Workstation PAH represents a robust, automated solution for regulatory-compliant PAH analysis in complex food and non-food matrices. It achieves high sensitivity, reproducibility, and throughput while minimizing sample preparation time and maintenance requirements.