Optimize the Agilent 1260 Infi nity Analytical SFC Solution with the Agilent 6150 Single Quadrupole MS

Importance of the topic

Supercritical fluid chromatography (SFC) offers higher separation speed and reduced backpressure compared to traditional HPLC, thanks to the low viscosity and high diffusivity of CO₂ mobile phases. Coupling SFC with mass spectrometry extends its utility in pharmaceutical, environmental, and food safety analysis by providing enhanced selectivity and sensitive detection.

Objectives and overview of the study

This technical overview aims to optimize the interface between the Agilent 1260 Infinity Analytical SFC Solution and the Agilent 6150 Single Quadrupole MS. The study evaluates the impact of effluent preheating and post-column make-up flow on MS signal quality, sensitivity, and reproducibility for an eight-compound standard mixture.

Methodology

The experimental design included:

• Preheating the SFC effluent in a secondary thermostatted column compartment at 30–60 °C
• Splitting the post-column flow to introduce a make-up solvent containing ammonium formate for improved ionization
• Comparing direct coupling versus preheated coupling and varying make-up flow rates (0.2–0.6 mL/min)
• Performing replicate injections (n=12) of a steroid and sulfonamide mix for statistical evaluation

Used instrumentation

• Agilent 1260 Infinity Analytical SFC Solution with SFC control module, binary pump, thermostatted column compartment (TCC), and backpressure regulator (BPR)
• Agilent 6150 Single Quadrupole MS with Jet Stream ion source
• Agilent ZORBAX Rx-SIL column (4.6 × 150 mm, 5 µm)
• Agilent OpenLAB CDS ChemStation software

Main results and discussion

Preheating the SFC effluent at 30–40 °C increased peak areas and heights by ~25% and improved signal-to-noise ratios from ~10 to >20. Peak area RSD decreased from ~12% to ~8–10%, and peak height RSD from ~13–16% to ~10–12%. Introducing a post-column make-up flow of 0.4 mL/min further reduced area RSD to ~6–8% without compromising signal intensity.

Benefits and practical applications

• Enhanced MS sensitivity and reproducibility in SFC analyses
• Prevention of source icing through controlled effluent heating
• Flexible ionization strategies without permanent additives in the CO₂ modifier
• Broad applicability in pharmaceutical profiling, environmental screening, and food quality control

Future trends and potential uses

Further enhancements may involve coupling with high-resolution MS, automated multi-temperature control, and advanced splitter designs for simultaneous multi-detector operation. Potential applications include chiral separations, metabolite profiling, and reaction monitoring in flow chemistry.

Conclusion

Optimizing effluent temperature and make-up flow in the Agilent 1260 Infinity SFC–MS configuration significantly improves analytical performance, delivering robust, sensitive, and adaptable workflows for diverse applications.

References

• Naegele E. Optimize the Agilent 1260 Infinity Analytical SFC Solution with the Agilent 6150 Single Quadrupole MS. Agilent Technologies Technical Overview, 2014.