Wearable solid-phase microextraction sampling for enhanced detection of volatile analytes in human ears.

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Environmental Science

Background:

• Molecular-level ear investigation is difficult due to limitations of traditional diagnostic methods.
• A need exists for noninvasive, sensitive, and convenient analytical techniques for ear analysis.

Purpose of the Study:

• To develop a novel wearable device for noninvasive molecular detection in the human ear.
• To establish a method for enhanced detection of trace analytes in the ear.

Main Methods:

• Development of a wearable sampling device integrating solid-phase microextraction (SPME) fibers into modified earmuffs (SPME-in-earmuffs).
• Utilizing gas chromatography-mass spectrometry (GC-MS) for the identification and quantification of extracted analytes.
• Demonstrating enhanced detection of volatile metabolites, environmental exposures, and therapeutic drugs in the ear.

Main Results:

• The SPME-in-earmuffs method successfully detected sport-induced metabolic changes, including fatty acids, aldehydes, and oxidative products.
• The method demonstrated excellent analytical performance for detecting ear medicines, with low limits of detection (0.005-0.021 ng/mL) and quantification (0.018-0.071 ng/mL).
• High linearity (R² > 0.99), good accuracy (84.43-150.18%), and acceptable precision (RSDs 13.19%-21.40%) were achieved.

Conclusions:

• This study presents the first wearable microextraction method for detecting volatile compounds in the human ear.
• The device enables headspace SPME sampling within the ear-muff enclosure, facilitating noninvasive monitoring.
• The method shows significant potential for applications in human health, disease diagnosis, and sports science.