Advancing Raman spectroscopy of erythrocytes with 3D-printed acoustofluidic devices

Abstract

Acoustofluidics is a technique that utilizes the forces produced by ultrasonic waves and fluid flows to manipulate cells or nano-/microparticles within microfluidic systems. In this study, we demonstrate the feasibility of performing the Raman analysis of living human erythrocytes (Erys) within a 3D-printed acoustofluidic device designed as a half-wavelength multilayer resonator. Experiments show that a stable and orderly Ery aggregate can be formed in the pressure nodal plane at the resonator's mid-height. This has a significant potential for improving the applicability of Raman spectroscopy in single Ery analysis, as evidenced by the acquisition of the spectrum of healthy and pre-heated Erys without substrate interference. Moreover, principal component analysis applied on the obtained spectra confirms the correct Ery group identification. Our study demonstrates that 3D-printed acoustofluidic devices can improve the accuracy and sensitivity of Raman spectroscopy in blood investigations, with potential clinical applications for noninvasive disease diagnosis and treatment monitoring.