Transfection of H9 is efficient and the resulting cells have a high viability. (a) Comparison of the Neon and Shuttle® Systems. Both systems can result in the efficient transfection of hESC. While the Neon system had a higher transfection efficiency, it also had increased variability between multiple transfections (36.2 ± 10.3% vs. 21.2 ± 0.8%). b) Transfected H9, phase contrast image (left panel) and GFP fluorescent image (right panel). (c) Quantification of Viability and Efficiency. FACS analysis demonstrates that after electroporation 73.5 ± 3.2% of the cells remain viable (compared to the 91.6 ± 2.7% viable in control reactions; P < 0.001) and that the transfection efficiency is 74.2 ± 1.4% (P < 0.001). (d) Viability and Transfection Efficiency in High Through-put Formats. All 96 wells of a shuttle plate were electroporated and the viability and efficiency of the first and last columns were compared. FACS analysis demonstrates that there is no change in viability between the first and last columns (61.8 ± 0.04% vs. 61.9 ± 0.03%, P > 0.05), however there is a small but significant decrease in transfection efficiency (41.0 ± 1.2% vs. 36.5 ± 1.3%, P < 0.05).