The biomechanical properties of populations of diseased cells are shown to have differences from healthy populations of cells, yet the overlap of these biomechanical properties can limit their use in disease cell enrichment and detection. We report a new microfluidic cell enrichment technology that continuously fractionates cells through differences in biomechanical properties, resulting in highly pure cellular subpopulations. Cell fractionation is achieved in a microfluidic channel with an array of diagonal ridges that are designed to segregate biomechanically distinct cells to different locations in the channel. Due to the imposition of elastic and viscous forces during cellular compression, which are a function of cell biomechanical properties including size and viscoelasticity, larger, stiffer and less viscous cells migrate parallel to the diagonal ridges and exhibit positive lateral displacement. On the other hand, smaller, softer and more viscous cells migrate perpendicular to the diagonal ridges due to circulatory flow induced by the ridges and result in negative lateral displacement. Multiple outlets are then utilized to collect cells with finer gradation of differences in cell biomechanical properties. The result is that cell fractionation dramatically improves cell separation efficiency compared to binary outputs and enables the measurement of subtle biomechanical differences within a single cell type. As a proof-of-concept demonstration, we mix two different leukemia cell lines (K562 and HL60) and utilize cell fractionation to achieve over 45-fold enhancement of cell populations, with high-purity cellular enrichment (90–99 %) of each cell line. In addition, we demonstrate cell fractionation of a single cell type (K562 cells) into subpopulations and characterize the variations of biomechanical properties of the separated cells with atomic force microscopy. These results will be beneficial to obtaining label-free separation of cellular mixtures or to better investigate the origins of biomechanical differences in a single cell type.
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Bongiorno T et al (2014) Mechanical stiffness as an improved single-cell indicator of osteoblastic human mesenchymal stem cell differentiation. J Biomech 47:2197–2204. doi:10.1016/j.jbiomech.2013.11.017
Bow H et al (2011) A microfabricated deformability-based flow cytometer with application to malaria. Lab Chip 11:1065–1073. doi:10.1039/c0lc00472c
Brown MJ, Hallam JA, Colucci-Guyon E, Shaw S (2001) Rigidity of circulating lymphocytes is primarily conferred by vimentin intermediate filaments. J Immunol 166:6640–6646
Chen J, Li J, Sun Y (2012) Microfluidic approaches for cancer cell detection, characterization, and separation. Lab Chip 12:1753–1767. doi:10.1039/c2lc21273k
Cho SH, Chen CH, Tsai FS, Godin JM, Lo YH (2010) Human mammalian cell sorting using a highly integrated micro-fabricated fluorescence-activated cell sorter (mu FACS). Lab Chip 10:1567–1573. doi:10.1039/c000136h
Choi S, Song S, Choi C, Park JK (2007) Continuous blood cell separation by hydrophoretic filtration. Lab Chip 7:1532–1538. doi:10.1039/b705203k
Choi SY, Karp JM, Karnik R (2012) Cell sorting by deterministic cell rolling. Lab Chip 12:1427–1430. doi:10.1039/c2lc21225k
Cross SE, Jin YS, Rao J, Gimzewski JK (2007) Nanomechanical analysis of cells from cancer patients. Nat Nanotechnol 2:780–783. doi:10.1038/nnano.2007.388
Dahl KN, Ribeiro AJS, Lammerding J (2008) Nuclear shape, mechanics, and mechanotransduction. Circ Res 102:1307–1318. doi:10.1161/circresaha.108.173989
Darling EM, Zauscher S, Block JA, Guilak F (2007) A thin-layer model for viscoelastic, stress-relaxation testing of cells using atomic force microscopy: do cell properties reflect metastatic potential? Biophys J 92:1784–1791. doi:10.1529/biophysj.106.083097
Franke T, Braunmuller S, Schmid L, Wixforth A, Weitz DA (2010) Surface acoustic wave actuated cell sorting (SAWACS). Lab Chip 10:789–794. doi:10.1039/b915522h
Glenister FK, Coppel RL, Cowman AF, Mohandas N, Cooke BM (2002) Contribution of parasite proteins to altered mechanical properties of malaria-infected red blood cells. Blood 99:1060–1063. doi:10.1182/blood.V99.3.1060
Gossett DR et al (2012) Hydrodynamic stretching of single cells for large population mechanical phenotyping. Proc Natl Acad Sci USA 109:7630–7635. doi:10.1073/pnas.1200107109
Guck J et al (2005) Optical deformability as an inherent cell marker for testing malignant transformation and metastatic competence. Biophys J 88:3689–3698. doi:10.1529/biophysj.104.045476
Hou HW, Bhagat AAS, Chong AGL, Mao P, Tan KSW, Han JY, Lim CT (2010) Deformability based cell margination—a simple microfluidic design for malaria-infected erythrocyte separation. Lab Chip 10:2605–2613. doi:10.1039/c003873c
Hur SC, Henderson-MacLennan NK, McCabe ERB, Di Carlo D (2011) Deformability-based cell classification and enrichment using inertial microfluidics. Lab Chip 11:912–920. doi:10.1039/c0lc00595a
Kim U, Soh HT (2009) Simultaneous sorting of multiple bacterial targets using integrated dielectrophoretic-magnetic activated cell sorter. Lab Chip 9:2313–2318. doi:10.1039/b903950c
Mao WB, Alexeev A (2011) Hydrodynamic sorting of microparticles by size in ridged microchannels. Phys Fluids 23. doi:10.1063/1.3590264
Otto O et al (2015) Real-time deformability cytometry: on-the-fly cell mechanical phenotyping. Nat Methods 12:199–202. doi:10.1038/nmeth.3281
Pamme N, Wilhelm C (2006) Continuous sorting of magnetic cells via on-chip free-flow magnetophoresis. Lab Chip 6:974–980. doi:10.1039/b604542a
Sawetzki T, Eggleton CD, Desai SA, Marr DWM (2013) Viscoelasticity as a biomarker for high-throughput flow cytometry. Biophys J 105:2281–2288. doi:10.1016/j.bpj.2013.10.003
Sethu P, Sin A, Toner M (2006) Microfluidic diffusive filter for apheresis (leukapheresis). Lab Chip 6:83–89. doi:10.1039/b512049g
Suresh S (2007) Biomechanics and biophysics of cancer cells. Acta Biomater 3:413–438. doi:10.1016/j.actbio.2007.04.002
Vahey MD, Voldman J (2008) An equilibrium method for continuous-flow cell sorting using dielectrophoresis. Anal Chem 80:3135–3143. doi:10.1021/ac7020568
Vona G et al (2000) Isolation by size of epithelial tumor cells—a new method for the immunomorphological and molecular characterization of circulating tumor cells. Am J Pathol 156:57–63. doi:10.1016/s0002-9440(10)64706-2
Wagner B, Tharmann R, Haase I, Fischer M, Bausch AR (2006) Cytoskeletal polymer networks: the molecular structure of cross-linkers determines macroscopic properties. Proc Natl Acad Sci USA 103:13974–13978. doi:10.1073/pnas.0510190103
Wang G, Mao WB, Byler R, Patel K, Henegar C, Alexeev A, Sulchek T (2013) Stiffness dependent separation of cells in a microfluidic device. PLoS One 8. doi:10.1371/journal.pone.0075901
Wang G, Crawford K, Turbyfield C, Lam W, Alexeev A, Sulchek T (2015) Microfluidic cellular enrichment and separation through differences in viscoelastic deformation. Lab Chip 15:532–540. doi:10.1039/c4lc01150c
Wen J, Arakawa T, Philo JS (1996) Size-exclusion chromatography with on-line light-scattering, absorbance, and refractive index detectors for studying proteins and their interactions. Anal Biochem 240:155–166. doi:10.1006/abio.1996.0345
Wolff A et al (2003) Integrating advanced functionality in a microfabricated high-throughput fluorescent-activated cell sorter. Lab Chip 3:22–27. doi:10.1039/b209333b
Xu WW, Mezencev R, Kim B, Wang LJ, McDonald J, Sulchek T (2012) Cell stiffness is a biomarker of the metastatic potential of ovarian cancer cells. PLoS One 7. doi:10.1371/journal.pone.0046609
Yamada M, Seki M (2005) Hydrodynamic filtration for on-chip particle concentration and classification utilizing microfluidics. Lab Chip 5:1233–1239. doi:10.1039/b509386d
Zhang WJ et al (2012) Microfluidics separation reveals the stem-cell-like deformability of tumor-initiating cells. Proc Natl Acad Sci USA 109:18707–18712. doi:10.1073/pnas.1209893109
This research was supported by NSF project number CBET-0932510, TI:GER program at Scheller College of Business at Georgia Tech, the Regenerative Engineering and Medicine Seed Grant, and the President’s Undergraduate Research Award (PURA) program at Georgia Tech. The authors would like to thank Dr. Wilbur Lam, Dr. Wenbin Mao, Dr. Hang Lu and Dr. Peter Hesketh for helpful discussions.
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Wang, G., Turbyfield, C., Crawford, K. et al. Cellular enrichment through microfluidic fractionation based on cell biomechanical properties. Microfluid Nanofluid 19, 987–993 (2015). https://doi.org/10.1007/s10404-015-1608-y
- K562 Cell
- HL60 Cell
- Biomechanical Property
- Cell Separation