DNAdelTM Gold Carrier Particles Optimized for Plasmid Delivery
The variability in DNA immobilization to particles, inherent in the current particle-mediated delivery protocols, has been highlighted many times in the literature.
However, there have been no reports of particle optimization with regard to increasing the amount of DNA bound to the particle surface, or to improving the amount
of the bound DNA released from the particle surface after intracellular delivery.
Using novel nanofabricated gold core carrier particles Seashell Technology has demonstrated an increase in both the overall number of transfected cells and transgene
expression levels following ballistic particle delivery.
The DNAdelTM gold carrier particles are supplied in three different sizes; 550 nm, 1000 nm and 1600 nm average diameter.
S550d, S1000d, S1600d
Improved Transfection Levels
Seashell Technology's S1100d gold carrier particles were coated with gWiz GFP expression plasmid using optimized protocols and delivered into Neuro2a cells using the Helios® gene gun. The GFP expression levels in the Neuro2A cells were compared to GFP expression in cells that had been treated with identical size gold carrier particles prepared using traditional precipitation methods. Image analysis of individually transfected cells allows for direct quantification of expression levels on a per cell basis. Representative data are shown in Figure 1. In this example, there is a greater than 4-fold increase in the total number of expressing cells and greater than 7-fold increase in the total amount of GFP expression in the cell population. The increase in expression level on an individual cell basis is highlighted by assessing the number of cells expressing at 10-fold over baseline detection. Using the Seashell particles there are more than 12 times as many cells expressing GFP at this high level than in the cell population transfected using the standard protocol.
Figure 1: GFP expression levels in Neuro2A cells following ballistic delivery using (A) Seashell DNAdelTM gold carrier particles (S1100d), or (B) the standard protocol. Equivalent amount of gold is delivered to each cell population. Quantitative image analysis was used both to count the total number of GFP expressing cells and the GFP expression level of each cell. In Panel (C) the number of cells expressing GFP at discrete levels above the baseline of GFP fluorescence detection is shown.
Improvements in overall transfection level using Seashell Technology gold carrier particles have been obtained in HeLa human epithelial carcinoma, Vero African Green Monkey kidney epithelial, A549 human lung carcinoma and MDA-MB-231 human epithelial adenocarcinoma cells.
This work was supported by NIH research grant 2R44EB001624-02A1.
This product is for research use only and is not intended for diagnostic use or to treat, cure or prevent any disease. The product is not available for resale. The safety of this material has not been determined and we recommend that this product and components are handled only by persons trained in laboratory techniques and are used in accordance with good laboratory practice. As all chemicals should be considered as potentially hazardous it is advisable when handling chemical reagents to wear suitable protective clothing. The BiolisticTM process is covered by patents owned by Dupont, Inc. and purchase of these products does not convey a license under these patents.