Agilent 1290 Infinity II LC with ISET– Emulation of the Agilent 1100 Series Binary LC for Analysis of Tricyclic Antidepressant Drugs

Importance of the Topic

HPLC is a cornerstone in pharmaceutical analysis, especially for tricyclic antidepressants in clinical chemistry and toxicology.
Transferring established methods between instruments typically requires time-consuming reoptimization.
Agilent Intelligent System Emulation Technology (ISET) enables seamless migration of legacy methods onto advanced UHPLC platforms, preserving chromatographic fidelity and boosting throughput.

Study Objectives and Overview

The aim of this study was to demonstrate the use of ISET in transferring a validated method for six tricyclic antidepressants from an Agilent 1100 Series binary LC to a 1290 Infinity II LC.
Key performance metrics such as retention time agreement and precision were evaluated with and without ISET enabled.

Methodology

The original method employed a ZORBAX Eclipse XDB-C18 column (4.6×75 mm, 3.5 µm) with a gradient from 60 % to 90 % methanol over 10 min in ammonium bicarbonate buffer (10 mM, pH 8) at 1 mL/min.
Injection volume was 1 µL, column temperature 50 °C, and DAD detection at 254 nm.

Used Instrumentation

• Agilent 1100 Series binary LC: binary pump G1312A, autosampler G1313A, column compartment G1316A, DAD G1315B.
• Agilent 1290 Infinity II LC: high-speed pump G7120A, multisampler G7167B, multicolumn thermostat G7116B, DAD G7117B.
• Software: OpenLab CDS ChemStation Edition C.01.07 with ISET 4.
• Reagents: LC-grade methanol, ultrapure water, ammonium bicarbonate buffer, tricyclic antidepressant standards.

Main Results and Discussion

Without ISET, retention times on the 1290 Infinity II LC were 6–9 % shorter than on the 1100 Series system due to reduced dwell volume and improved mixing.
Enabling ISET yielded retention time deviations below 1 %, corresponding to over 99 % agreement with the original method.
Precision metrics improved significantly: retention time RSDs decreased by up to tenfold on the 1290 Infinity II LC with ISET compared to the 1100 Series system, while peak area RSDs were also reduced.

Benefits and Practical Applications

• No method reoptimization is required when migrating legacy HPLC protocols to advanced UHPLC platforms.
• Consistent chromatograms and data comparability are maintained across instruments.
• Enhanced precision reduces analytical uncertainty in routine QC or clinical laboratories.
• Streamlined workflows increase laboratory efficiency and method robustness.

Future Trends and Potential Applications

Deployment of system emulation is expected to expand to additional legacy instruments and workflows.
Integration with mass spectrometry and automated data analytics will further accelerate method translation.
Emerging applications include environmental and food analysis, where legacy methods remain in use.

Conclusion

Agilent ISET on the 1290 Infinity II LC enables true instrument-to-instrument method transfer, preserving historic HPLC protocols with high fidelity and enhanced performance. This technology simplifies method migration, ensures data consistency, and boosts analytical precision for pharmaceutical applications.

References

1. Gratzfeld-Huesgen A. Agilent 1290 Infinity Binary LC with ISET – Emulation of the Waters Alliance 2695 LC System Analyzing Analgesics. Agilent Technologies Application Note; 2013, publication 5991-2792EN.
2. Gratzfeld-Huesgen A. Seamless instrument-to-instrument method transfer from an Agilent 1100/1200 Series LC to an Agilent 1290 Infinity LC using Intelligent System Emulation Technology (ISET). Agilent Technologies Application Note; 2011, publication 5990-9113EN.
3. Huber U. Analysis of Tricyclic Antidepressant Drugs by HPLC. Agilent Technologies Application Note; 2002, publication 5988-7626EN.
4. Agilent Technologies. 1290 Infinity II with ISET User Manual; 2015, part number G4220-90314.