Thermoset polyester as an alternative material for microchip electrophoresis/electrochemistry

Area of Science:

• Analytical Chemistry
• Materials Science
• Separation Science

Background:

• Microchip electrophoresis with electrochemical detection (MCE-EC) is a sensitive technique for small molecule analysis.
• Polymers like PDMS are common in MCE-EC but have limitations in separation efficiency and surface stability.
• Alternative polymers like PMMA and PC offer better separation but are difficult to fabricate.

Purpose of the Study:

• To characterize thermoset polyester (TPE) as a novel material for MCE-EC devices.
• To evaluate TPE's performance compared to traditional materials like PDMS.
• To explore surface modifications of TPE for enhanced performance.

Main Methods:

• Fabrication and characterization of TPE microchips in native and plasma-oxidized states.
• Surface modification of TPE using polyelectrolyte multilayers (PEMs).
• Performance evaluation of TPE MCE-EC devices, including separation efficiency and electroosmotic flow (EOF).

Main Results:

• TPE microchips demonstrated significantly higher separation efficiencies (up to 295,000 N/m) than PDMS.
• TPE exhibited higher and more consistent electroosmotic flow across a range of pH values compared to PDMS.
• TPE surfaces were successfully modified with PEMs to control surface chemistry and charge.

Conclusions:

• Thermoset polyester is a promising alternative material for MCE-EC applications.
• TPE offers superior separation efficiency and EOF stability with simpler fabrication than existing polymer options.
• PEM coatings provide a versatile method for tailoring TPE surface properties for MCE-EC.