Automated Switching Between 1D-LC and Comprehensive 2D-LC Analysis – The Agilent 1290 Infinity 2D-LC Solution

Significance of the Topic

Comprehensive two-dimensional liquid chromatography (LC×LC) addresses the limitations of conventional one-dimensional LC by greatly increasing peak capacity and resolving complex mixtures. In many applications such as food analysis, pharmaceuticals, and environmental monitoring, detailed profiling of sample constituents demands the enhanced separation power that LC×LC can provide. Integrating both 1D and 2D modes on a single platform enables laboratories to balance throughput and resolution without hardware modifications.

Study Objectives and Overview

This technical overview presents a flexible configuration of the Agilent 1290 Infinity 2D-LC Solution that allows switching between 1D-LC and comprehensive LC×LC with a few clicks. Using phenolic compounds in virgin olive oil as a test case, the study demonstrates that incorporating an additional two-position/ six-port valve does not compromise chromatographic performance in either mode.

Methodology and Instrumentation

The system was assembled from standard Agilent modules and software. A two-position/six-port valve was installed in the column compartment to route flow for 1D or 2D modes. For modulation in LC×LC, a two-position/four-port duo valve alternately filled two loops, which were then eluted onto a second-dimension column. Method parameters were adjusted for each mode:

• 1D-LC used a phenyl-hexyl column, shallow water/methanol gradient, 0.2 mL/min flow and diode array detection at 260 nm
• LC×LC employed the same first-dimension column coupled to a C18 second-dimension column, low-flow gradient (0.05 mL/min) in dimension one and fast gradient (3 mL/min) in dimension two with 30 s modulation cycles

Used Instrumentation

• Agilent 1290 Infinity 2D-LC Solution including two binary pumps, autosampler with thermostat, thermostatted column compartment, diode array detector, valve drive module
• Additional two-position/six-port valve for mode switching and two-position/four-port duo valve for modulation
• Software: Agilent OpenLAB CDS ChemStation Edition and GC Image LC×LC Edition for data processing

Main Results and Discussion

Overlay comparisons of 1D-LC runs with and without the additional valve showed identical retention profiles and peak shapes, indicating no adverse effect on separation. In LC×LC mode, two-dimensional contour plots of olive oil phenolics also matched closely between configurations. Minor retention time shifts observed for late-eluting fractions were attributed to modulation timing rather than valve performance. Overall, the extra valve did not introduce band broadening or loss in sensitivity.

Benefits and Practical Applications

• Flexible workflow: seamless switching between high-throughput 1D analysis and high-resolution LC×LC without hardware reconnections
• Reduced downtime: method changeovers performed in software with one click
• Broad applicability: valuable for laboratories requiring both routine screening and detailed characterization of complex samples such as oils, pharmaceuticals, and natural products

Future Trends and Potential Applications

Advances in gradient design and faster second-dimension cycles will further exploit the full two-dimensional separation space, improving resolution for next-generation analyses. Integration with high-resolution mass spectrometry and automated data processing workflows will enable deeper insights into complex matrices. Emerging fields such as proteomics and metabolomics stand to benefit from routine, flexible LC×LC implementations.

Conclusion

The Agilent 1290 Infinity 2D-LC Solution, equipped with an additional two-position/six-port valve, provides an efficient platform for alternating between standard 1D-LC and comprehensive 2D-LC methodologies via simple software commands. Demonstrated using phenolic profiling in olive oil, the configuration maintains chromatographic integrity in both modes and offers laboratories a versatile tool for diversified analytical demands.

References

• Dugo et al. Comprehensive multidimensional liquid chromatography: theory and applications. J. Chromatogr. A 2008, 1184, 353–368
• Giddings R.C. Two-dimensional separations: concept and promise. Anal. Chem. 1984, 56, 1258A–1264A
• Duck et al. Determination of peak distribution in LC×LC. J. Chromatogr. A 2012, 1246, 69–75
• International Olive Council. COI/T.20/DOC.29, 2009. Determination of biophenols in olive oils by HPLC
• Naegele E. Performance evaluation of the Agilent 1290 Infinity 2D-LC Solution. Agilent Technol. Technical Overview 2012, publication 5991-0138EN
• Krieger S., Schneider S. Quality Analysis of Extra Virgin Olive Oils Part 7. Agilent Technol. Application Note 2014, publication 5991-4515EN