Two-Step Acoustic Cell Separation Based on Cell Size and Acoustic Impedance─toward Isolation of Viable Circulating Tumor Cells
(2025) In Analytical Chemistry 97(4). p.2120-2126- Abstract
Isolation and characterization of circulating tumor cells (CTCs) present a noninvasive alternative to monitor disease progression in individual patients. However, the heterogeneous lineage specificity of CTCs makes it difficult to isolate and identify possible CTCs by a liquid biopsy. Better label-free methods for the isolation of viable CTCs are needed. Our solution is a combined approach that is inherently epitope independent. Cells are separated by size-sensitive acoustophoresis using an ultrasonic standing wave field, followed by size-insensitive, acoustic barrier-medium focusing, which enables the enrichment of viable cancer cells in blood. With standard acoustophoresis in homogeneous medium, lymphocytes and monocytes were... (More)
Isolation and characterization of circulating tumor cells (CTCs) present a noninvasive alternative to monitor disease progression in individual patients. However, the heterogeneous lineage specificity of CTCs makes it difficult to isolate and identify possible CTCs by a liquid biopsy. Better label-free methods for the isolation of viable CTCs are needed. Our solution is a combined approach that is inherently epitope independent. Cells are separated by size-sensitive acoustophoresis using an ultrasonic standing wave field, followed by size-insensitive, acoustic barrier-medium focusing, which enables the enrichment of viable cancer cells in blood. With standard acoustophoresis in homogeneous medium, lymphocytes and monocytes were efficiently removed, while removal of granulocytes from the target MCF7 breast cancer cells was not possible due to overlapping acoustic migration velocities for viable cells. Remaining granulocytes were removed by a second separation step with an acoustic impedance barrier-medium selectively blocking the transport of MCF7 cells to generate a clean cancer cell fraction. For two series of 500 mL samples containing 5 × 105 white blood cells, spiked with 2 × 104 or 1 × 103 MCF7 cells, the recovery of MCF7 cells was 77.3% with a 99.9% depletion of white blood cells in the final cancer cell fraction. The most abundant contaminating cell type was granulocytes (85.9% of remaining cells). Nearly all lymphocytes (99.996%) and monocytes (99.995%) were depleted. A two-step acoustic cell separation based on cell size and acoustic impedance is well suited to generate a purified cancer cell fraction as a preparatory step for downstream single-cell analysis.
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- author
- Magnusson, Cecilia LU ; Rezayati Charan, Mahdi LU and Augustsson, Per LU
- organization
-
- Clinical Chemistry, Malmö (research group)
- Acoustofluidics group (research group)
- LUCC: Lund University Cancer Centre
- NanoLund: Centre for Nanoscience
- LTH Profile Area: Engineering Health
- LTH Profile Area: Nanoscience and Semiconductor Technology
- LU Profile Area: Light and Materials
- MultiPark: Multidisciplinary research focused on Parkinson´s disease
- Division for Biomedical Engineering
- LTH Profile Area: Photon Science and Technology
- publishing date
- 2025
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Analytical Chemistry
- volume
- 97
- issue
- 4
- pages
- 7 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85215394891
- pmid:39818757
- ISSN
- 0003-2700
- DOI
- 10.1021/acs.analchem.4c04911
- language
- English
- LU publication?
- yes
- id
- c3b22ff2-acec-404e-9b11-98b461769c41
- date added to LUP
- 2025-04-01 15:25:14
- date last changed
- 2025-06-10 20:23:15
@article{c3b22ff2-acec-404e-9b11-98b461769c41, abstract = {{<p>Isolation and characterization of circulating tumor cells (CTCs) present a noninvasive alternative to monitor disease progression in individual patients. However, the heterogeneous lineage specificity of CTCs makes it difficult to isolate and identify possible CTCs by a liquid biopsy. Better label-free methods for the isolation of viable CTCs are needed. Our solution is a combined approach that is inherently epitope independent. Cells are separated by size-sensitive acoustophoresis using an ultrasonic standing wave field, followed by size-insensitive, acoustic barrier-medium focusing, which enables the enrichment of viable cancer cells in blood. With standard acoustophoresis in homogeneous medium, lymphocytes and monocytes were efficiently removed, while removal of granulocytes from the target MCF7 breast cancer cells was not possible due to overlapping acoustic migration velocities for viable cells. Remaining granulocytes were removed by a second separation step with an acoustic impedance barrier-medium selectively blocking the transport of MCF7 cells to generate a clean cancer cell fraction. For two series of 500 mL samples containing 5 × 10<sup>5</sup> white blood cells, spiked with 2 × 10<sup>4</sup> or 1 × 10<sup>3</sup> MCF7 cells, the recovery of MCF7 cells was 77.3% with a 99.9% depletion of white blood cells in the final cancer cell fraction. The most abundant contaminating cell type was granulocytes (85.9% of remaining cells). Nearly all lymphocytes (99.996%) and monocytes (99.995%) were depleted. A two-step acoustic cell separation based on cell size and acoustic impedance is well suited to generate a purified cancer cell fraction as a preparatory step for downstream single-cell analysis.</p>}}, author = {{Magnusson, Cecilia and Rezayati Charan, Mahdi and Augustsson, Per}}, issn = {{0003-2700}}, language = {{eng}}, number = {{4}}, pages = {{2120--2126}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Analytical Chemistry}}, title = {{Two-Step Acoustic Cell Separation Based on Cell Size and Acoustic Impedance─toward Isolation of Viable Circulating Tumor Cells}}, url = {{http://dx.doi.org/10.1021/acs.analchem.4c04911}}, doi = {{10.1021/acs.analchem.4c04911}}, volume = {{97}}, year = {{2025}}, }