Fig. 4

Biocompatibility of the elastomer microfluidic chips. a, b. All experiments used chips as in Additional file 4C. a. Fission yeast cells were injected in a lectin-coated microchip, and medium was perfused (20 μL/min) at 32 °C. After 2 h, images were acquired over > 5 h to calculate generation times and cell sizes at division. Results from a newly cut elastomer chip were compared to those obtained with re-used chips (> 10 times) and in control batch cultures. For each parameter in the first two columns (flask and chip), the average of 3 independent experiments is shown with the standard error. Size at division: n ≥ 50. Generation time in chips: n > 20. Data for individual chips (last three columns) are shown with their standard deviations. Old: re-used chips. b. DIC images of cells grown in the chips in a at the indicated times. Scale bars = 10 μm. c. HeLa cells were injected in a chip or in a standard culture dish at similar densities and grown for 28 h at 37 °C. A constant flow of medium (5 μL/min) was applied in the chip after cells were allowed to adhere to the glass (~ 3 h after injection, T = 0). At T = 0, 5.4 and 8.2% of cells were in mitosis (rounded or in duplets prior to cytokinesis) in flask and in chip, respectively (n ≥ 100). At T = 28 h, 2.8 and 7.5% of cells were in mitosis in flask and in chip, respectively (n ≥ 100). The chip used the perfusion channel as in Additional file 4C but no temperature channel (see Methods): to simplify this proof-of-concept assay, sample temperature was maintained by a high precision hot plate. For this, chip and tubings were pre-incubated overnight with 2 mg/mL BSA at 4 °C and washed with medium prior to cell injection. Bright-field images. Scale bars = 100 μm