An automated parallel multi-channel chromatographic system for isotopic analysis - Demonstration considering Sr

Area of Science:

• Analytical Chemistry
• Chromatography
• Automation

Background:

• Automated systems are crucial for high-throughput chemical analysis.
• Closed-column chromatography offers advantages in sample purification and contamination prevention.
• Developing robust automated purification systems is essential for complex sample matrices.

Purpose of the Study:

• To develop and validate a fully automated, closed-column chromatographic system with parallel multi-channel capabilities.
• To assess the system's performance in terms of cleaning, channel consistency, and blank levels.
• To demonstrate the system's efficacy in purifying Strontium (Sr) from geological reference materials.

Main Methods:

• A novel automated, closed-column chromatographic system was designed and constructed.
• The system incorporates multiple reagent reservoirs, a multi-channel syringe pump, 10-port valves, and automated sample tubes and fraction collection.
• Performance was evaluated through automated cleaning tests, bubble interference studies, channel consistency checks, and blank measurements.
• Strontium purification from BCR-2, JB-2, JB-3, and NIST SRM 987 reference materials was performed.

Main Results:

• The automated cleaning of sample tubes effectively eliminates residue.
• Bubbles were found to have no adverse effect on column performance.
• Excellent consistency was observed across parallel channels, with negligible system blank.
• Strontium recoveries exceeded 89.4%, with a procedural blank below 200 pg.
• Purified Sr isotope values showed excellent agreement with certified reference values.

Conclusions:

• The developed automated, closed-column chromatographic system provides efficient, reliable, and high-throughput sample purification.
• The system demonstrates excellent performance characteristics, including high recovery, low blank, and good reproducibility.
• This automated system is suitable for the precise purification of elements like Strontium from various reference materials.