Novel Pinhole Emitter Chip for Micro Supercritical Fluid Chromatography-Mass Spectrometry with Integrated...

Area of Science:

• Analytical Chemistry
• Chemical Engineering
• Materials Science

Background:

• Supercritical fluid chromatography (SFC) is a powerful separation technique.
• Coupling SFC with mass spectrometry (MS) enhances analytical capabilities.
• Existing SFC-MS interfaces face challenges with mobile phase decompression and back-pressure control.

Purpose of the Study:

• To develop a novel chip-based device for seamless SFC-MS coupling.
• To integrate fluidic back-pressure regulation for supercritical mobile phases.
• To improve the efficiency of analyte transfer from supercritical fluid to the MS interface.

Main Methods:

• Fabrication of monolithic microfluidic chips using selective laser-induced etching.
• Integration of comb-shaped particle retention structures for column packing.
• Development of a restrictive pinhole MS emitter for controlled decompression.
• Inclusion of an arrowhead-shaped fluidic element for precise back-pressure regulation.

Main Results:

• The chip-based device enables facile coupling of packed capillary SFC columns with atmospheric pressure ionization MS.
• The integrated pinhole emitter achieves controlled decompression of supercritical CO2 mobile phase.
• Precise, dilution-free back-pressure regulation with minimal postcolumn volume (3 nL).
• Demonstrated rapid SFC-MS analysis of pharmaceuticals and natural products with excellent performance.

Conclusions:

• The novel micro SFC-MS platform offers significant advantages for analytical separations.
• The integrated design simplifies the coupling of SFC with MS.
• This technology enables efficient and sensitive analysis of complex samples.