Thermo Scientific Accucore Biphenyl columns are designed for robust and reliable separations with unrivaled performance

Significance of the Topic

Reliable and reproducible chromatographic separations are essential in analytical chemistry, particularly when resolving aromatic, moderately polar, or isomeric compounds. The development of biphenyl stationary phases addresses limitations of traditional C18 columns by offering complementary selectivity, improved isomer resolution, and robustness for complex sample matrices.

Objectives and Overview of the Study

This application note evaluates the performance of Thermo Scientific Accucore Biphenyl columns in separating drugs of abuse and steroid analytes. Key goals include demonstrating enhanced selectivity over C18 phases, assessing long-term column stability, and verifying lot-to-lot reproducibility under routine gradient conditions.

Methodology and Used Instrumentation

• Stationary phase: Solid-core biphenyl, 2.6 µm particle size, 80 Å pore size, 6 % carbon load, end-capped.
• Column dimensions: 2.1 × 50 mm and 2.1 × 100 mm.
• Guard configuration: Accucore Biphenyl Defender guards (2.1 × 10 mm) with guard cartridge holder.
• Mobile phase: Methanol-water gradients, compatibility with 100 % aqueous start.
• Operating conditions: pH 2–8, temperature up to 70 °C, pressure limits up to 600–800 bar.
• Detection: Coupled to mass spectrometry with diversion of matrix ions to minimize interference.

Key Results and Discussion

The biphenyl column exhibited: enhanced resolution of isomeric opioids (e.g., morphine vs. oxymorphone), steroids (e.g., 21-deoxycortisol, 11-deoxycortisol, corticosterone) with changed elution order compared to C18, and high separation efficiency without UHPLC pressure demands. Resolution factors exceeded 1.6 for critical pairs. Over 6000 injections of urine matrix showed minimal loss of peak shape or resolution, outperforming competitor chemistries. Three manufacturing lots delivered nearly identical retention and selectivity profiles, confirming reproducibility.

Benefits and Practical Applications of the Method

• Complementary selectivity to C18 for aromatic and polar analytes.
• Improved isomer and isobar separation for forensic, clinical, and environmental analyses.
• Lower backpressures—compatible with conventional HPLC systems.
• Robust performance: >6000 injections with maintained resolution.
• Excellent lot-to-lot consistency for routine workflows.
• Compatibility with fully aqueous conditions for polar compound retention.

Future Trends and Potential Applications

Advancements may include further tailoring of stationary-phase chemistries for specific analyte classes, integration with high-resolution mass spectrometry for enhanced selectivity, development of greener mobile phases, and automation of method development using orthogonal column selectivity. Expanding biphenyl-based phases to larger biomolecules or environmental contaminants represents additional growth areas.

Conclusion

Thermo Scientific Accucore Biphenyl columns deliver robust, high-resolution separations for aromatic, moderately polar, and isomeric analytes. Their complementary selectivity to C18, combined with exceptional durability and reproducibility, makes them valuable for diverse analytical applications requiring reliable performance.