After transfection of mPSCs, aspirate the media from the six-well plate. Then add 200 microliters of trypsin into each well. Swirl and incubate for 30 seconds at 37 degrees Celsius.
Tap the side of the plate and add 200 microliters of ice cold FACS buffer. Using a P200 pipette, mix the contents of each well to dislodge cells and make single cell solutions. Transfer 200 microliters from each well to the appropriate well on the 96-well plate Centrifuge the plate at 300 G for five minutes.
After centrifugation, resuspend the pellets in 150 microliters of FACS buffer before running the sample on a flow cytometer. Compared to reverse transfections, forward transections showed a significantly lower proportion of cells positive for the marker. Interestingly, forward Transfect did not deliver a significantly lower amount of DNA on average to the population of cells.
In reverse transections, incubation time significantly influenced the percentage of reporter positive cells. However, the average reporter expression in positive cells was not affected by incubation time. For both poly and co-transfection, a forward transfection significantly decreased the number of cells present at the chosen endpoint compared to reverse transfections.
In the case of reverse poly-transections, higher transfection efficiency and a broader dynamic range of well-represented DNA ratios were observed.