Trypsin ethylenediaminetetraacetic acid trypsin edta solution

For a cell imaging experiment, a highly invasive human prostate cancer cell (PC-3) line was used. PC-3 cells were purchased from ATCC (Manassas, VA, USA) and maintained in complete growth medium which consisted of ATCC formulated F12-K medium (Kaighn’s modification) supplemented with 10% v/v fetal bovine serum (FBS) and 100 U/mL penicillin/streptomycin. Cells were seeded at a density of 1.3 × 104 cells/cm² and cultured in 5% CO₂ at 37 °C. A trypsin-ethylenediaminetetraacetic acid (trypsin-EDTA) solution was purchased from Invitrogen (Invitrogen, Grand Island, NY, USA) and used for cell suspension. Hank’s balanced salt solution (HBSS) was purchased from Invitrogen (Grand Island, NY, USA) for maintaining cells during the cell experiment. After suspending the cell from the petri dish, HBSS was used to neutralize the trypsin-EDTA for the cell safety.

Human breast cancer cell lines, MDA-MB-231 and MCF-7, were purchased from ATCC (Manassas, VA, USA) and maintained in modified complete medium (RPMI, 10% fetal bovine serum, 10 mM HEPES, 2 mM L-glutamine, 1 mM sodium-pyruvate, 0.05 mM 2-mercaptoethanol, and 11 mM D-glucose). They were cultured in 5% CO ${}_2$ at 37 ${}^{\circ }$ C. The SBAT traps and deforms a single-cell in a suspended cell, so a trypsin-ethylenediaminetetraacetic acid (trypsin-EDTA) solution obtained from Invitrogen (Grand Island, NY, USA) was used to detach cultured cells from the bottom of the Petri dish. After the addition of trypsin-EDTA into the culture dish, the cells were incubated at 37 ${}^{\circ }$ C for 2 min. An equivalent volume of modified complete medium was added to neutralize the trypsin. Phosphate buffer solution (PBS) was purchased from Invitrogen (Grand Island, NY, USA) for washing cells before acoustic tweezer experiments. With the inverted microscope, we confirmed that the cell was slightly touching or floating on the Petri dish without morphological damage. During experiments, cells with blebs were excluded from the sample for measurements. The cell viability test also validated that there was no significant adverse effect on the cell’s condition during the experiment.