High-throughput cell and spheroid mechanics in virtual fluidic channels

• Published in: Nature communications 2020-05, Vol.11 (1), p.2190-2190, Article 2190
• Main Authors: Panhwar, Muzaffar H., Czerwinski, Fabian, Dabbiru, Venkata A. S., Komaragiri, Yesaswini, Fregin, Bob, Biedenweg, Doreen, Nestler, Peter, Pires, Ricardo H., Otto, Oliver
• Format: Article
• Language: English
• Subjects: 13/106; 13/31; 13/62; 49; 631/1647/2163; 631/1647/2204; 631/1647/277; 639/766/189; 639/766/747; Algorithms; Biological properties; Biological samples; Biophysics; Channels; Cleanrooms; Clusters; Design modifications; Dimethylpolysiloxanes - chemistry; Elastic Modulus - physiology; Equipment Design; Flow Cytometry; HEK293 Cells; HL-60 Cells; Humanities and Social Sciences; Humans; Hydrodynamics; Liquid-liquid interfaces; Lithography; Mechanical properties; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Microfluidics; Microfluidics - instrumentation; Microfluidics - methods; Models, Theoretical; Modulus of elasticity; multidisciplinary; Polyethylene Glycols - chemistry; Replicating; Rheological properties; Rheology; Science; Science (multidisciplinary); Spheroids, Cellular
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-15813-9

Microfluidics by soft lithography has proven to be of key importance for biophysics and life science research. While being based on replicating structures of a master mold using benchtop devices, design modifications are time consuming and require sophisticated cleanroom equipment. Here, we introduce virtual fluidic channels as a flexible and robust alternative to microfluidic devices made by soft lithography. Virtual channels are liquid-bound fluidic systems that can be created in glass cuvettes and tailored in three dimensions within seconds for rheological studies on a wide size range of biological samples. We demonstrate that the liquid-liquid interface imposes a hydrodynamic stress on confined samples, and the resulting strain can be used to calculate rheological parameters from simple linear models. In proof-of-principle experiments, we perform high-throughput rheology inside a flow cytometer cuvette and show the Young’s modulus of isolated cells exceeds the one of the corresponding tissue by one order of magnitude. High-throughput rheological measurements of cells and cell clusters by microfluidics is limited by fixed channel dimensions. Here the authors create virtual fluidic channels inside the cuvette of commercial flow cytometers to dynamically tune channel cross section to enable rheological measurements from cells and cell clusters.