First, dilute cells with phosphate buffered saline (PBS), or saline solution, with around 500 milliliters of solution for every 25,000 cells. Next, prepare the centrifuge by inserting, sealing and clamping slides, with the slides facing out, not in.
Next, load cells and spin them at speed level 10 for four minutes, or level 13 for six minutes for smaller cells. After withdrawing the saline solution from each slide, add an equal amount of 4 percent pulverized fuel ash (PFA), a preservative, to preserve the cells. Next, repeat the spin cycle.
Next, wash each slide with saline solution twice. Use a special pen called a "pap pen" to make squares around the cells. Finally, keep cells moist with more saline solution and let sit in a humidity chamber at 4 degrees Celsius until you need them.