Figure 2. Comparison of NucleoBond Xtra kits' yields and speed to those of competitor products. Plasmid DNA was isolated following each manufacturer's protocol using the maximum culture volume with high plasmid content. The yield of plasmid DNA was determined after DNA precipitation. NucleoBond Xtra and competitor kits including a desalting tool were compared in Panel A, left side (midi) and Panel A, right side (maxi), while kits without a desalting tool (requiring centrifugation for DNA precipitation) were compared in Panel B, left side (midi) and Panel B, right side (maxi). Note that the yields of plasmid DNA are slightly lower for kits including the desalting tool than for kits without the desalting tool, due to the residual DNA remaining on the tool.

Figure 3. Comparison of transfection efficiencies using plasmid DNA purified with NucleoBond Xtra Maxi and a competitor product. A 6-kb high-copy plasmid expressing gephyrin fused to an EGFP reporter was transfected into HEK293 cells after purification with NucleoBond Xtra Maxi (Panel A) or Product Q (Panel B). Plasmid purification from E. coli DH5α was performed according to each manufacturers' instructions using the maximum culture volume with high plasmid content. NucleoBond Xtra Maxi yielded 1,222 μg of plasmid with an A_260/280 of 1.84. Product Q yielded 557 μg of plasmid with an A_260/280 of 1.86. HEK293 cells in 12-well plates (2.5 x 10⁴ cells/well) were transfected for 48 hr with 0.1–0.25 μg/well of plasmid DNA using FuGENE HD/6 (Roche, 1.5 μl/well). Data kindly provided by Prof. Dr. Guenter Schwarz, Institute of Biochemistry, University of Cologne, Germany.

Figure 4. Transfection of primary rat hippocampal neurons using plasmid DNA purified with NucleoBond Xtra EF. A 9-kb high-copy plasmid expressing neuroligin fused to a GFP reporter was transfected into primary rat hippocampal neurons after purification with NucleoBond Xtra EF. Plasmid purification from E. coli XL1-Blue was performed according to the manufacturer's instructions. Primary rat hippocampal neurons were cultured in vitro for six days and transfected with 1 µg of plasmid DNA per well using calcium phosphate. The neurons were visualized by fluorescence microscopy 48 hr post-transfection. Data kindly provided by Dr. Nina Wittenmayer, Ruprecht-Karls-University Heidelberg, Institute for Anatomy and Cell Biology, Dept. of Medical Cell Biology, Heidelberg, Germany.

Figure 5. Endotoxin-free DNA for transfection of primary rat hippocampal neurons. A 4.5-kb high-copy plasmid was transfected into primary rat hippocampal neurons after purification from E. coli DH5α with NucleoBond Xtra Maxi Plus EF. Primary rat hippocampal neurons were cultured in vitro for 14 days and transfected with 1 µg of plasmid DNA per well using NeuroMag transfection reagent (OZ Biosciences). The neurons were visualized by fluorescence microscopy 48 hr post-transfection. Data kindly provided by OZ Biosciences, Marseille, France.

Figure 6. Comparison of the NucleoBond Xtra and NucleoBond Xtra EF procedures.