Acoustophoresis is an emerging technology allowing cell separation based on their physical properties via ultrasound. The compressibility and density of the cell and its surrounding medium
define an acoustic contrast factor (ACF), which governs the migration direction of the cell. Different cell types with distinct ACFs would be separable by acoustophoresis. This innovative method
has the advantages to be non-contact, label-free, and working in a controlled flow. Those features make it a promising solution for any bioproduction process requiring isolation and processing
of cells without the disadvantages of centrifugation or immunomagnetic separation. It has already been successfully used in various clinical applications: isolation of blood components,
circulating tumor cells, and exosome.

The Stromal Vascular Fraction (SVF) is an heterogenous cell population contained within adipose tissue and composed of Adipose tissue-derived Mesenchymal Stromal Cells (AD-MSCs),
endothelial cells, Leukocytes, and pericytes. Although being increasingly used in regenerative medicine for various clinical indications including orthopedic disorders, and wound healing, the
SVF therapy is not fully understood. The main mechanisms and the role of each cell type are not well defined yet.

Objective: In this study, we developed a method to measure the ACF of any cells. We measured the ACF of AD-MSCs and cell lines similar to the SVF.