A Cost-Efficient Multiwavelength LED-Based System for Quantitative Photoacoustic Measurements

Area of Science:

• Biomedical Optics
• Photoacoustic Imaging
• Sensing Technology

Background:

• Photoacoustic (PA) sensing offers high sensitivity for deep tissue optical absorption.
• Conventional PA systems are often bulky, costly, and limited in wavelength availability due to laser requirements.

Purpose of the Study:

• To develop a compact, cost-efficient, multiwavelength photoacoustic sensing system.
• To enable quantitative measurements of biomolecules in turbid tissues.

Main Methods:

• Utilized two high-power LED sources (444 nm and 628 nm) and a single ultrasonic transducer (3.5 MHz).
• Investigated LED performance in pulsed mode and PA response dependence on concentration and energy fluence.
• Employed tissue-mimicking phantoms with optical absorption and scattering properties.

Main Results:

• Demonstrated quantitative measurements with absolute deviations between 0.4% and 12.3% for spectral unmixing of two absorbers.
• Validated the system's performance using phantoms with controlled optical properties.
• Achieved accurate estimations of absorber concentrations.

Conclusions:

• The developed LED-based PA system is a viable, cost-effective alternative to laser-based systems.
• This technology holds potential for in-vivo multiparametric biomarker measurements (e.g., hemoglobin oxygenation, melanin, lipids, glucose).
• Future upgrades could enhance diagnostic capabilities for various biomedical applications.