Detection of Asthma Inhaler Use via Terahertz Spectroscopy.

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Pharmacology

Background:

• Inhaled medications are widely used for respiratory conditions but also as performance-enhancing drugs.
• Current detection methods for inhaled substances have limitations, including lag times and complexity.
• Monitoring the procurement and use of inhaled medications is challenging due to diverse acquisition channels.

Purpose of the Study:

• To introduce Terahertz (THz) spectroscopy as a novel method for detecting inhaled medications.
• To assess the feasibility of detecting propellants in exhaled breath as a proxy for inhaled medication use.
• To demonstrate the potential for a point-of-care device for real-time monitoring.

Main Methods:

• Application of Terahertz (THz) spectroscopy to analyze exhaled breath samples from human subjects.
• Quantification of the propellant HFA-134a in breath after the use of a pressure-mediated inhaler.
• Simulations to evaluate the detection of next-generation propellants like HFA-152a.

Main Results:

• Successfully detected and quantified the propellant HFA-134a in human breath up to 30 minutes post-inhalation.
• Demonstrated that THz spectroscopy can identify HFA-134a, a common propellant in asthma inhalers.
• Simulations confirmed the capability to detect next-generation propellants (HFA-152a) with the same THz approach.

Conclusions:

• Terahertz spectroscopy offers a viable, non-invasive method for detecting inhaled medication use via propellants in exhaled breath.
• A single point-of-care THz sensor can identify the use of pressure-mediated inhalers (pMDIs) without hardware modification.
• This technology has implications for monitoring medication adherence and detecting performance-enhancing drug use in sports.