SunBridge HPLC Column

Significance of the Topic

Reversed-phase liquid chromatography is a cornerstone technique in analytical chemistry, underpinning quality control, pharmaceutical analysis and environmental monitoring. The ability to maintain stable retention and peak shapes under highly aqueous mobile phases or extreme pH is critical for reliable quantification of polar, basic and metal-chelating compounds. Innovations in column packing and bonding chemistries directly impact method robustness and reproducibility.

Objectives and Study Overview

This study compares the performance and stability of a newly developed SunBridge C18 column with a commercially available Hybrid C18 column from Company W. Key goals are to assess retention changes under 100% aqueous conditions, evaluate peak symmetry for challenging analytes, and benchmark column stability under alkaline (pH 11.5) and acidic (pH 1.0) environments.

Methodology and Instrumentation

• Columns: SunBridge C18, 5 μm, 150 × 4.6 mm; Company W Hybrid C18, 5 μm, 150 × 4.6 mm (also tested 3.5 μm and 1.7 μm variants).
• Mobile phases:
    • 100% water for retention stability test (10 mM phosphate buffer, pH 7.0).
    • CH₃OH/H₂O (75/25) for plate count and selectivity evaluations.
    • Methanol/50 mM phosphate (pH 11.5) and ACN/1% TFA (pH 1.0) for durability tests.
• Flow rates: 1.0 mL/min for 3.5 and 5 μm columns; 0.2–0.4 mL/min for 1.7 μm.
• Temperature: 40 °C (up to 80 °C for pH 1.0 study).
• Detection: UV absorbance at 250 nm.
• Sample analytes: Uridine/uridine analogs, adenine, pyridine, phenol, caffeine, oxine, nortriptyline, amitriptyline and mixed test probes for hydrogen bonding, hydrophobicity and steric selectivity.

Main Results and Discussion

The SunBridge C18 column demonstrated superior retention stability under 100% aqueous conditions, showing only a 4% decrease in retention factor after a one-hour static hold versus a 40% loss on Company W Hybrid C18. Peak symmetry for basic and metal-chelating compounds (e.g., oxine, nortriptyline) was markedly improved on SunBridge, with reduced tailing factors and higher plate counts (N≈10 000–13 500) compared to N≈6 000–9 000 on the hybrid column. Under alkaline (pH 11.5) and acidic (pH 1.0) durability tests, SunBridge maintained 90–100% of its initial theoretical plate count over extended elution times, outperforming other hybrid C18 products by an order of magnitude, attributed to its bidentate end-capping chemistry.

Benefits and Practical Applications

• Enhanced hydrolytic stability enabling direct analysis in high-water mobile phases without loss of retention.
• Improved peak shape for basic and metal-chelating analytes reduces need for ion-pair reagents.
• Broader pH operating range (1.0–11.5) supports method flexibility for acidic and basic compounds.
• Robust performance under elevated temperatures aids high-throughput assay development.

Future Trends and Potential Applications

Development of hybrid silica phases with advanced multipoint bonding and tailored end-capping will further extend column lifetimes and selectivity. Miniaturized UHPLC formats and sub-2 μm particle packs will deliver higher throughput and resolution. Integration of chromatographic data with machine-learning algorithms promises automated method optimization and predictive maintenance of column health.

Conclusion

Overall, SunBridge C18 exhibits exceptional retention stability under 100% aqueous conditions, superior peak symmetry for challenging analytes and outstanding durability across extreme pH ranges. These attributes position it as a versatile tool for demanding analytical applications in pharmaceuticals, environmental testing and life-science research.

Reference

No external literature references were provided in the source document.