Comprehensive study on the characterization of lysed blood samples using dual-wavelength photoacoustics

Anemia is a global health concern, prompting the need for rapid, accurate, and noninvasive diagnostic tools. This has led to significant interest in the development of various optical tools, including photoacoustic (PA) spectroscopy for monitoring and quantification of clinically relevant blood parameters.

Estimating the blood lysis level (LL) and oxygenation ( ${\mathrm{SO}}_2$ ) is essential for the detection of various hemolytic conditions, including anemia. The PA spectroscopy is explored here for quantifying hemolytic blood samples.

In vitro PA measurements on human blood samples were validated through simulation studies involving discrete dipole approximation, Monte Carlo, and k-Wave methods. Blood hematocrit (H), LL, and ${\mathrm{SO}}_2$ levels are determined from simulated and experimental PA signals.

The wavelength pairs 700-905 and 700-1000 nm are found to be optimal for the estimation of H and ${\mathrm{SO}}_2$ with high accuracy ( $>90\%$ ). The correlation coefficient between the actual and evaluated LLs is calculated to be $\approx 0.90$ .

Results show that PA measurements with a suitable combination of optical wavelengths can be used for determining the important blood parameters accurately and simultaneously. Further investigation is needed to apply the developed method under an in vivo setting.