Analysis Using Dual Ion Source DUIS-2010 (Part 1)

Importance of the Topic

Liquid chromatography–mass spectrometry relies on efficient ionization to achieve sensitivity, stability and quantitative accuracy across a wide range of compounds. The dual ion source DUIS-2010 integrates electrospray ionization and atmospheric pressure chemical ionization into a single interface, streamlining analysis of analytes with diverse polarities and reducing method development time.

Objectives and Overview

This study evaluates the performance of the DUIS-2010 dual ion source using three test compounds: streptomycin, acetophenone and butyl paraben, representing high, low and medium polarity analytes. Comparative results from standalone ESI and APCI sources are presented to illustrate the versatility and efficiency gains offered by DUIS-2010.

Methodology and Instrumentation

Sample preparation involved mixing streptomycin (200 µg/mL), acetophenone (400 µg/mL) and butyl paraben (200 µg/mL) in methanol-water solution. Chromatographic separation was performed on a C8 column with a water-methanol gradient at 0.5 mL/min.

• Column: Phenomenex Mercury MS C8 (10 mmL x 4.0 mm I.D., 5 µm)
• Mobile phase: water (A) and methanol (B); gradient 35% to 95% B
• Flow rate: 0.5 mL/min, injection volume: 2 µL

Použitá instrumentace

• Liquid chromatograph coupled to a mass spectrometer via DUIS-2010 dual ion source
• Dual source block heater and drying gas interface
• ESI region with +4.5 kV probe voltage and APCI corona needle with adjustable discharge
• Heated capillary (CDL) temperatures: 250 ˚C for DUIS and ESI, 300 ˚C for APCI
• Scan range m/z 50–650 with 0.5 s cycle time

Key Results and Discussion

The DUIS-2010 enabled detection of all three analytes within a single run. Streptomycin generated protonated and methanol adduct ions under ESI and DUIS-2010, while APCI led to in-source fragmentation. Acetophenone was effectively ionized by APCI and DUIS-2010 but not by ESI alone. Butyl paraben was detectable with all ionization modes. Overall, DUIS-2010 provided comparable sensitivity and spectral quality to dedicated sources while covering a wider polarity range.

Benefits and Practical Applications

• Eliminates manual source switching and method optimization between ESI and APCI
• Reduces total analysis time and operator workload
• Supports simultaneous screening of compounds with diverse chemical properties
• Suitable for high-throughput laboratories in pharmaceutical, environmental and food testing

Future Trends and Opportunities

Development of integrated triple-mode sources including APPI, automated polarity switching, and real-time method selection using predictive algorithms could further enhance LC-MS flexibility. Broader adoption in metabolomics, forensic analysis and QA/QC workflows is anticipated.

Conclusion

The DUIS-2010 dual ion source offers a robust solution for LC-MS analysis of compounds with varying polarities. By combining ESI and APCI in one interface, it streamlines workflows, improves throughput and maintains high sensitivity.

Reference

No specific literature references were provided in the source document.