Time-domain photoacoustic waveform analysis for glucose measurement

Area of Science:

• Biomedical Optics
• Spectroscopy
• Chemical Sensing

Background:

• Photoacoustic (PA) effect arises from light-ultrasound interactions, with waveforms containing rich sample information beyond optical absorption.
• Conventional PA spectroscopy primarily uses optical absorption, neglecting inherent mechanical and thermal properties within the PA waveform.
• These underutilized properties correlate with target composition but are not exploited in current methods.

Purpose of the Study:

• To propose and demonstrate time-domain photoacoustic waveform spectroscopy (tPAWS) for chemical component quantification.
• To leverage multiple inherent variables within the PA waveform for enhanced feature extraction.
• To improve sensitivity and accuracy in chemical measurements compared to existing techniques.

Main Methods:

• Developed time-domain photoacoustic waveform spectroscopy (tPAWS) for chemical analysis.
• Utilized multiple inherent variables from the PA waveform excited by a single laser wavelength.
• Applied tPAWS for glucose measurement in human blood serum (HBS).

Main Results:

• tPAWS demonstrated superior sensitivity and accuracy for glucose measurement in HBS.
• Achieved significant enhancements compared to conventional amplitude-based PA measurement.
• Outperformed near-infrared (NIR) spectroscopy in sensitivity and accuracy.

Conclusions:

• tPAWS offers a novel, physics-inspired sensing method for chemical analysis.
• The technique avoids the need for multiple wavelengths and complex instrumentation.
• tPAWS shows potential to complement or surpass current spectroscopic methods for chemical quantification.