Journal: Science Advances

Article Title: Space-time acoustofluidic tweezers for dynamic and selective manipulation of microparticles

doi: 10.1126/sciadv.aee2983

Figure Lengend Snippet: ( A ) Working principle of STAT. (i) Two orthogonal standing SAW fields with slightly detuned frequencies, ω x and ω y , pattern PACPs (red) and NACPs (blue) in distinct pressure regions; inset: photo of the STAT chip. (ii) Pressure-field evolution over one detuning cycle (0 to 2π/Δω), showing dynamic shifts of pressure nodes and antinodes induced by the frequency difference Δω. (iii) Schematic of the dynamic, static, and drag forces acting on PACPs and NACPs. ( B ) (i) High-throughput, low-frequency, shear-like oscillation of PACPs under the dynamic force field distribution. (ii) Time-lapse images over one oscillation cycle with 10-μm polystyrene beads in water. ( C ) (i) High-throughput, low-frequency, longitudinal-like oscillation of NACPs within patterned PACPs. Time-lapse images over one oscillation cycle with PDMS clusters within an arrayed pattern of 10 μm polystyrene beads. (ii) Experimental demonstration of selective navigation of a PDMS cluster through a locally stationary polystyrene-bead lattice. ( D ) Schematics and experiments showing that STAT enables (i) gentle oscillation of biological cells and (ii) controllable transport of NACPs while maintaining cells in a patterned lattice. In (B) to (D), the polystyrene beads, PDMS clusters, and K562 cells are highlighted in red, blue, and light green, respectively. Oscillation was captured at ω x /2π = 20.094 MHz and ω y /2π = 20.094 MHz − 1 Hz, corresponding to Δω = 1 × 2π Hz, when P x > P y . In (C) and (D), black and green arrows represent transport and oscillation directions, respectively. Scale bars, 45 μm.

Article Snippet: K562 suspension cells and B16-F10 adherent melanoma cells were cultured in RPMI 1640 [American Type Culture Collection (ATCC), 30-2001] and Dulbecco’s modified Eagle’s medium (ATCC, 30-2002), respectively.

Techniques: High Throughput Screening Assay, Shear, Gentle

Journal: Science Advances

Article Title: Space-time acoustofluidic tweezers for dynamic and selective manipulation of microparticles

doi: 10.1126/sciadv.aee2983

Figure Lengend Snippet: ( A ) Images of K562 cells, showing a half-cycle oscillation with ζ x and ζ y denoting oscillation displacements in x and y . ( B ) Measured cell oscillation displacements as functions of frequency detuning Δω. Green bars show ζ x , while blue bars indicate ζ y . ( C ) Measured cell oscillation displacements as functions of driving voltage amplitudes V x when V y = 11 V pp and V y when V x = 11 V pp . ( D ) Schematics illustrating how tuning Δ P and Δω controls the transport of a PDMS cluster between a lattice pattern of K562 cells, showing gentle oscillations around stable pressure nodes. ( E ) Time-elapse images of tuning Δω and Δ P to selectively manipulate a PDMS cluster through an effectively stationary K562 cell pattern.

Article Snippet: K562 suspension cells and B16-F10 adherent melanoma cells were cultured in RPMI 1640 [American Type Culture Collection (ATCC), 30-2001] and Dulbecco’s modified Eagle’s medium (ATCC, 30-2002), respectively.

Techniques: Gentle

Journal: Nature Communications

Article Title: Single-cell laser emitting cytometry for label-free nucleolus fingerprinting

doi: 10.1038/s41467-024-51574-5

Figure Lengend Snippet: a Experiment setup of the scanning-based SLEC. The cells were sandwiched within a mirror-formed FP cavity. The upper mirror was spin-coated with a dye-doped PS layer, functioning as the gain medium. By adjusting the pump energy, lasing emissions can be achieved only within the nucleolus regions. b Laser threshold and emitting spectrum in regions with and without nucleolus. c Co-localization of the laser emission image with phase contrast image and fluorescence image from nucleolus dye. A549 cells were cultured on the lower mirror as an illustrative example. Scale bar: 5 μm. d Enlarged comparison among phase contrast image, laser emission image and fluorescence image. Scale bar: 5 μm. The lasing emission image indicated distinct subareas attributed to the nucleolus’ inhomogeneity of the refractive index (red arrows indicated). e Configuration of the scanning-based SLEC for tissue sections. f Configuration of the flow-based SLEC for suspended cells. Phase contrast image of a live K562 cell (20X objective), the nucleolus laser emission hyperspectral image and its spectrum. Scale bar: 5 μm. Each nucleolus corresponds to its unique laser peak.

Article Snippet: The Caco-2 cells and suspension K562 cells from ATCC were cultured in RPMI 1640 with 10% FBS and 100 U mL −1 penicillin/streptomycin.

Techniques: Fluorescence, Cell Culture, Comparison, Refractive Index

Journal: Nature Communications

Article Title: Single-cell laser emitting cytometry for label-free nucleolus fingerprinting

doi: 10.1038/s41467-024-51574-5

Figure Lengend Snippet: a Configuration of the SLEC chip mounted on the microscope system and the schematic of the flow cytometry. Scale bar: 20 μm. b Four main parameters extracted from the nucleolus laser spectrum. c Phase contrast images of the suspension cells K562 and the Caco−2 cells in the suspension state. Scale bar: 20 μm. d Nucleolus laser spectral fingerprints in laser peak number, average laser peak intensity, laser peak intensity variance, and low intensity (<3e3) percentage. (A549: n = 1121, K562: n = 1182, Caco−2: n = 1276, C2C12: n = 1227). e t-SNE visualization of the laser spectral data of nucleolus. Source data are provided as a Source Data file.

Article Snippet: The Caco-2 cells and suspension K562 cells from ATCC were cultured in RPMI 1640 with 10% FBS and 100 U mL −1 penicillin/streptomycin.

Techniques: Microscopy, Flow Cytometry, Suspension

Journal: Analytical Chemistry

Article Title: Increasing Fluid Viscosity Ensures Consistent Single-Cell Encapsulation

doi: 10.1021/acs.analchem.3c05243

Figure Lengend Snippet: Cell flow dynamics and encapsulation in phosphate-buffered saline. The lymphoblast (K562) cells suspended in 1× PBS buffer are being continuously injected into a microfluidics device, and cells passing through the observation chamber on a microfluidics device are counted every 20 s. (A) Time trace of cells traversing the observation chamber in 1× PBS buffer (ρ sol = 1.00 g/mL). The inset displays the same data but with the Y -axis (cell count) in a log scale. The cell flow dynamics exhibited three characteristic stages (I, II, III) that markedly differed in droplet occupancies by single cells, 0.01 > λ > 1. (B) Digital photographs of droplets collected at different time points during the experiment. The cells are highlighted in red.

Article Snippet: K562 suspension lymphoblast cells (ATCC) and 9e10 semiadherent mouse hybridoma cells (ATCC) were cultured in RPMI 1640 and IMDM mediums, respectively, both supplemented with 10% (v/v) FBS and 1× PS.

Techniques: Encapsulation, Saline, Injection, Cell Counting

Journal: Analytical Chemistry

Article Title: Increasing Fluid Viscosity Ensures Consistent Single-Cell Encapsulation

doi: 10.1021/acs.analchem.3c05243

Figure Lengend Snippet: Cell flow dynamics in density-adjusted and viscosity-adjusted buffers. The time traces of lymphoblast (K562) cells are being continuously injected into the microfluidics device in density-adjusted and viscosity-adjusted buffers. (A) Cell flow dynamics in a density-adjusted buffer (ρ sol = 1.053 g/mL) composed of 1× PBS and 20% Optiprep. The inset displays the same data but with the Y -axis (cell count) in a log scale. (B) Cell flow dynamics in PBS buffer having different density values. (C) Cell flow dynamics in a viscosity-adjusted buffer (μ sol = 75 cPs) composed of 1× PBS and 15% dextran. The inset displays the same data but with the Y -axis (cell count) in a log scale. (D) Infusion of different types of cells in a viscosity-adjusted buffer. Solid symbols represent cell loading in 1× PBS supplemented with 15% dextran, and open symbols represent cell loading in 1× PBS supplemented with 0.05% xanthan gum. (E) Droplet occupancy over time in the presence of 15% dextran (MW 500k). (F) Droplet occupancy over time in the presence of 0.05% xanthan (MW 2000k). Scale bars: 100 μm.

Article Snippet: K562 suspension lymphoblast cells (ATCC) and 9e10 semiadherent mouse hybridoma cells (ATCC) were cultured in RPMI 1640 and IMDM mediums, respectively, both supplemented with 10% (v/v) FBS and 1× PS.

Techniques: Viscosity, Injection, Cell Counting