Interface for Reproducible, Multishot Direct Analysis of Solid-Phase Microextraction Samples.

Area of Science:

• Analytical Chemistry
• Mass Spectrometry
• Separation Science

Background:

• Coupling solid-phase microextraction (SPME) sampling with ambient mass spectrometry presents unique analytical challenges.
• Existing methods often lack the ability to perform discrete analyses on multiple locations of a single SPME fiber.

Purpose of the Study:

• To describe and validate a novel enclosed interface for direct analysis in real time (DART) probe, SPME fiber, and high-resolution mass spectrometry.
• To enable discrete, reproducible analyses from different areas of a single SPME fiber.

Main Methods:

• Development of an enclosed interface integrating DART, SPME, and mass spectrometry.
• Optimization of inlet flow speed and desorption temperature.
• Demonstration of reproducibility through replicate analyses on derivatized SPME fibers and sequential sampling events.

Main Results:

• The interface allows up to three technical replicate measurements from one sampling event on a single SPME fiber.
• Reproducibility was demonstrated with analyte measurement center of variance (CV) ranging from 3% to 6%.
• Conditioning of the SPME fiber using the enclosed DART was successfully performed.

Conclusions:

• The developed interface is a straightforward addition to existing commercial technologies for SPME/DART/MS.
• The system offers high reproducibility for analyzing multiple sample aliquots from a single SPME fiber.
• Machine diagrams are provided for custom components, facilitating adoption.