Improving sensitivity for microchip electrophoresis interfaced with inductively coupled plasma mass spectrometry...

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Microchip electrophoresis inductively coupled plasma mass spectrometry (MCE-ICP-MS) is a powerful technique for elemental analysis.
• Enhancing sensitivity and speed in MCE-ICP-MS is crucial for routine speciation analysis.

Purpose of the Study:

• To improve the sensitivity of MCE-ICP-MS using multichannel parallel separation.
• To evaluate the impact of parallel separation on separation efficiency and resolution.
• To demonstrate the application of the enhanced system for mercury speciation analysis.

Main Methods:

• Implementation of multichannel parallel separation with 2-20 array lanes in MCE-ICP-MS.
• Optimization of separation conditions including electric field strength and background electrolyte.
• Analysis of mercury species (Hg(2+) and methylmercuric ion) in a certified reference fish sample.

Main Results:

• Sensitivity of the MCE-ICP-MS system was proportionally enhanced by 2-20 folds with multichannel separation.
• No significant adverse effects on column efficiency and resolution were observed.
• Rapid separation of Hg(2+) and methylmercuric ion within 36s was achieved.
• Detection limits for Hg(2+) and methylmercuric ion were reduced to 6.8-7.1 ng/L.
• Recoveries for mercury species in certified reference fish ranged from 94-98%.

Conclusions:

• Multichannel parallel separation offers a significant sensitivity enhancement for MCE-ICP-MS.
• The developed method provides high efficiency, rapid analysis, and low detection limits for metal speciation.
• This technique is highly beneficial for routine analysis in environmental, biological, and food fields.