Using the Agilent 1290 Infinity II Multicolumn Thermostat with Extreme Temperatures and Flow Rates

Overview of Agilent 1290 Infinity II Multicolumn Thermostat Performance at Extreme Conditions

Significance of the Topic

The ability to control column temperature across a broad range while maintaining precise solvent flow is critical in high-performance liquid chromatography. This flexibility supports method development for thermally sensitive analytes, enhances throughput for routine QA/QC tasks, and enables challenging separations that demand either high selectivity or rapid cycle times.

Objectives and Study Overview

This study evaluates the Agilent 1290 Infinity II Multicolumn Thermostat under extreme operating conditions. A mixture of nine standard compounds (eight phenones and acetanilide) was analyzed to assess retention time precision and separation efficiency at temperatures of 4, 40, and 90 °C and flow rates from 0.2 to 3.5 mL/min. A reference method at 40 °C and 0.5 mL/min provided baseline performance metrics.

Methodology and Instrumentation

• LC system: Agilent 1290 Infinity II with Flexible Pump, Vialsampler, and Multicolumn Thermostat featuring two independently controlled zones.
• Columns: ZORBAX RRHD SB-C18 (2.1 × 50 mm, 1.8 µm) for standard/low-flow tests; ZORBAX SB-C18 (4.6 × 50 mm, 3.5 µm) for high-flow trials.
• Heat exchangers: Agilent Quick-Connect in standard, high-flow, and low-dispersion configurations.
• Detection: Diode Array Detector with a 10 mm Max-Light cell at 240 nm signal, 360 nm reference.
• Software: Agilent OpenLAB CDS ChemStation Edition C.01.07 SR1.

Main Results and Discussion

Retention time precision (RSD) remained below 0.08 % across all test conditions. Key findings include:

• Reference method (40 °C, 0.5 mL/min): baseline separation in 3.5 min, RSDs ≤ 0.06 %.
• Low-flow/low-temperature (4 °C, 0.2 mL/min): RSDs up to 0.07 %, stable separation over 7 min.
• Low-flow/high-temperature (90 °C, 0.2 mL/min): RSDs ≤ 0.076 %, improved selectivity with gentle peak broadening.
• High-flow/low-temperature (4 °C, 2.5 mL/min): separation in 1.8 min, RSDs < 0.033 %.
• High-flow/high-temperature (90 °C, 3.5 mL/min): separation in < 0.8 min, RSDs < 0.07 %, demonstrating ultrafast throughput.

The independent second temperature zone showed no impact on performance, underscoring the system’s capability for parallel column regeneration or temperature programming.

Practical Benefits and Applications

• Enhanced method development flexibility for thermally labile or closely eluting compounds.
• High throughput analysis with sub-minute separations and robust precision supports large-scale QA/QC laboratories.
• Simultaneous column conditioning allows continuous operation and reduced cycle times.

Future Trends and Applications

Advances may include integration with automated method scouting, real-time temperature optimization, and expansion to multi-dimensional LC workflows. Further miniaturization of heat exchangers and integration with machine-learning-based gradient design could enhance both speed and selectivity in complex sample analyses.

Conclusion

The Agilent 1290 Infinity II Multicolumn Thermostat delivers exceptional retention time precision and separation efficiency across a wide temperature (4–90 °C) and flow (0.2–3.5 mL/min) range. Its dual-zone design and Quick-Connect heat exchangers offer unmatched flexibility for routine analyses, method development, and high-throughput applications.

References

1. Schneider, S. Performance Characteristics of the Agilent 1290 Infinity II Multicolumn Thermostat. Agilent Technologies Technical Overview, publication 5991-5533EN, 2015.