Thiol-ene micropillar array electrospray ionization platform for zeptomole level bioanalysis.

Area of Science:

• Analytical Chemistry
• Biotechnology
• Materials Science

Background:

• Micropillar array electrospray ionization (μPESI) is a key technique in mass spectrometry.
• Developing robust and versatile μPESI platforms is crucial for sensitive bioanalysis.
• Thiol-ene chemistry offers advantages in fabricating microfluidic devices.

Purpose of the Study:

• To introduce a novel μPESI platform fabricated using thiol-ene chemistry.
• To demonstrate the bioanalytical capabilities of the developed μPESI platform.
• To evaluate the performance of polyethylene glycol (PEG) coated μPESI chips.

Main Methods:

• Fabrication of a μPESI platform using thiol-ene polymers.
• Coating of individual μPESI chips with polyethylene glycol (PEG).
• Analysis of protein, protein digest, and cell lysate samples using mass spectrometry.

Main Results:

• The thiol-ene PEG-coated μPESI chip supports a broad range of aqueous-organic solvent compositions.
• Demonstrated bioanalysis of complex biological samples including protein and cell lysate.
• Achieved a detection limit at the 60 zeptomole level (6 × 10⁻²⁰ mol) for a peptide standard.

Conclusions:

• The developed μPESI platform offers high sensitivity and versatility for bioanalytical mass spectrometry.
• Thiol-ene PEG coating enhances chip compatibility with diverse solvent systems.
• This technology represents a significant advancement for sensitive peptide and protein analysis.