Improved purification of problematic compounds using Waters Maxpeak Premier OBD preparative columns with an integrated inert surface

Importance of the Topic

Preparative liquid chromatography is essential for isolating target compounds from complex mixtures at high purity and yield. Metal-sensitive "sticky" molecules often interact with conventional stainless steel surfaces, leading to poor peak shape, reduced sensitivity and unpredictable recovery. Addressing these challenges accelerates downstream processing and reduces solvent waste.

Objectives and Study Overview

This study evaluated MaxPeak Premier OBD preparative columns with an integrated inert surface for isolating B-group vitamins and unknowns from a commercial vitamin beverage. The goals were to compare performance against stainless steel preparative columns, demonstrate scale-up predictability, and quantify improvements in peak shape, sensitivity, run time and fraction volume.

Methodology and Instrumentation

The workflow began with UPLC analysis on 2.1×50 mm, 1.7 µm ACQUITY UPLC BEH C18 stainless steel and Premier BEH C18 columns at 0.35 mL/min. Preparative separations used 10×150 mm, 5 µm and 10×100 mm, 3.5 µm MaxPeak Premier OBD columns at 5.4 mL/min. Mobile phases were 20 mM ammonium formate pH 5.05 (A) and methanol (B), with UV detection at 270 nm.

Instrumentation:

• Analytical: ACQUITY UPLC H-Class System with Quaternary Solvent Manager, Sample Manager, Column Manager, TUV and QDa detectors
• Preparative: Waters AutoPurification System with 2545 Binary Gradient Module, 2767 Sample Manager, System Fluidics Organizer and 2998 PDA detector

Results and Discussion

Scale-up from analytical to preparative columns was predictable, with consistent elution order and symmetrical peaks. Compared to stainless steel OBD columns, Premier columns delivered 5–30 % higher peak areas and heights, improved sensitivity for low-level targets, and eliminated the need for time-consuming pre-conditioning. The 3.5 µm column reduced run time by >33 % while maintaining similar resolution. Peak widths at half-height were narrower on Premier columns, leading to smaller fraction volumes and faster dry-down.

Benefits and Practical Applications

• Enhanced purity and recovery of metal-sensitive compounds thanks to inert surfaces that prevent non-specific adsorption
• Predictable scale-up from UPLC to preparative scale ensures reproducible collection
• Reduced run times and solvent consumption lower process cost and waste
• Smaller fraction volumes accelerate downstream handling and drying
• No pre-conditioning required, saving time and increasing throughput

Future Trends and Opportunities

Continued miniaturization and integration of inert-surface columns will drive faster, more efficient single-use purifications. Combining preparative UPLC with automated fraction handling and in-line analytics could further optimize recovery of trace impurities. Expanding inert surface technologies to other stationary phases and larger preparative formats will broaden applicability in pharmaceutical, biotech and natural-products workflows.

Conclusion

MaxPeak Premier OBD preparative columns with integrated inert surfaces significantly improve purification of problematic, metal-sensitive compounds. They offer scalable performance, improved peak shape and sensitivity, reduced runtimes and fraction volumes, and eliminate pre-conditioning steps. These advancements enhance efficiency and reliability of preparative workflows.

References

1. DeLano M, Walter T, Lauber M, Gilar M, Jung M, Nguyen J, Boissel C, Patel A, Bates-Harrison A, Wyndham K. Analytical Chemistry. DOI: 10.1021/acs.analchem.0c05203.
2. Yang J, Rainville P. Enhancing the LC-MS/MS Analysis of B-group Vitamins with MaxPeak High Performance Surfaces Technology. Waters Application Note 720007264, 2021.
3. Waters Corporation. Topics in Liquid Chromatography, Part 2: Optimum Bed Density Columns. White Paper 720001939.
4. Berthelette K, DeLoffi M, Collins C, Kalwood J, Walter T. Correlation Between the Adsorption of Acidic Analytes on Stainless Steel Columns and Their Ionic Charge. Waters Application Note 720008792.