Impact of staining on cell acoustic properties.

Cell staining techniques are essential for cell visualization and bioanalysis, providing valuable insights into cellular structure, function, and behavior. Despite their significance, the impact of staining processes, such as dye penetration, adsorption, or hydrogen bonding, on the physical properties of cells remains largely unexplored. Acoustic methods have proven effective in noninvasively probing various cell properties. In this study, we examine how different staining methods affect the acoustic properties of live DU145, MCF-7, Jurkat, and BV2 cell lines by comparing their acoustic impedance with and without staining. Our results show that calcein staining reduces the acoustic impedance of MCF-7 cells by 2.7%, whereas no noticeable changes are observed in other cases. This reduction, unique to MCF-7 cells, is most consistent with a modest increase in cell compressibility, potentially reflecting subtle alterations in membrane or cytoplasmic mechanics during dye and low-percent DMSO exposure.