On-line polydopamine coating as a new way to functionalize polypropylene fiber sorbent for solid phase extraction

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Polypropylene fibers offer mechanical stability but are hydrophobic, limiting the extraction of polar compounds.
• On-line solid phase extraction (SPE) requires sorbent materials with good wettability for efficient analyte capture.

Purpose of the Study:

• To develop an effective on-line solid phase extraction (SPE) process using polydopamine-coated polypropylene fibers.
• To enhance the extraction efficiency of polar compounds in a two-dimensional ultra-high-performance liquid chromatography (2D UHPLC) system.

Main Methods:

• Developed an automated and reproducible in situ polydopamine coating process for polypropylene fibers.
• Optimized dopamine concentration, flow rate, and polymerization time for the coating process.
• Evaluated the performance of the modified cartridges using chlorogenic acid as a model compound in a 2D UHPLC system.

Main Results:

• Achieved hydrophilization of the polypropylene fiber surface, improving wettability and polar compound extraction.
• Optimized conditions involved 20 mg dopamine in 25 mL mixture, a flow rate of 2.07 mL/min, and 60 min polymerization time.
• Demonstrated an overall process reproducibility of 3.61% (n=24) across eight cartridges in the 2D UHPLC system.

Conclusions:

• The developed polydopamine coating process is effective for preparing polypropylene fiber sorbents for on-line SPE.
• The modified sorbent material enables efficient extraction of polar compounds with high reproducibility in 2D UHPLC.
• This method offers a robust solution for on-line sample preparation in complex analytical workflows.