Maximizing transfection efficiency: The importance of plasmid DNA quality

In this application note, Zymo Research emphasizes the significant impact of plasmid DNA quality on transfection success. Four key points are highlighted:

• The DNA should be predominantly supercoiled and free of genomic DNA and RNA, as circular plasmids are more efficiently taken up by cells, while contamination confuses quantification.
• The DNA should be highly concentrated and devoid of phenol, salts, and protein to prevent dilution of transfection reagents, skewed absorbance readings, and inhibition of DNA-lipid complex formation.
• It is crucial to ensure the DNA is free of endotoxins, as these impurities reduce transfection efficiency and harm sensitive cells.
• Confirming the correct sequence of the plasmid is vital for achieving experimental objectives and serves as a good assessment of its purity and suitability for transfections. Maintaining a good absorbance spectrum is essential for optimal results.