Sinofection is a superior cationic polymer-based transfection reagent. It has been successfully applied to transfection at various scales over a broad range of cell lines. Compared with the leading transfection reagents on the market, Sinofection yields higher protein expression level and exhibits lower cytotoxicity. It is an ideal choice for recombinant protein production for both transient and stable transfection. Its extensive compatibility with serum, cell type, scale, and storage temperature offers you ease and assurance for research and production.
Transfection with Sinofection has been proved to provide higher levels of protein expression in several cell lines than leading competitor’s products. For large-scale production of recombinant proteins, Sinofection is the best choice to achieve the optimum yield. In addition, Sinofection also exhibits high transfection efficiency to ensure successful transfections.
Fig. 1 Protein expression levels by transient transfection using Sinofection and other competitors were compared in 9 cell lines, 6 of which showed superior results transfected by Sinofection (A~F). Protein expression level was determined by ELISA assay. The transfection by competitor transfection reagents followed the manufacturers’ protocols.
Hundreds of recombinant antibodies and proteins have been successfully expressed by transient or stable transfection with Sinofection at various scales, from 0.1mL in a 96-well plate to 50L in a bioreactor. Utilizing Sinofection for all scales of transfection application will save the cost of research and production to a great extent.
1、Transfection protocol (35-mm dish):
(1) Preparation of cells
(2) Preparation of Sinofection&DNA complexes
Dilute DNA with appropriate diluents, such as PBS, NaCl solution, glucose solution, DMEM, medium with or without serum, whichever is isotonic, to a concentration of 20 μg/mL (optimization recommended) and a total volume of 250 μL.
Dilute Sinofection of appropriate amount in 250 μL of medium.
Combine the diluted DNA with the diluted Sinofection (total volume = 500 μL). Mix gently and incubate for 20 minutes at room temperature (solution may appear cloudy).
Add the 500 μL complexes drop-wise to cells and medium. Gently rock the dishes or wells to ensure even distribution.
Incubate cells at 37°C in a CO2 incubator for 18-48 hours (normally high expression is achieved after 72 hours) prior to protein expression assay.
2、Transfection protocol (flask)：
Transfecting Cells for Protein ExpressionThis protocol is typically used to transfect DNA into 293 EBNA or CHO cells cultured in flasks. Use sterile DNA or filter-sterilize DNA before use (re-quantify your DNA after filtration).
All amounts are on a per flask basis for 30 mL cultures in a 125 mL shake flask; for other formats, see Table 2. Scaling up or Down Transfections.
Table 2. Scaling up or down transfections with Sinofection. Note: the actual conditions should be optimized by experiments.
Sinofection demonstrates very low cytotoxicity which is tested and verified by in-house WST-8 assay for each lot. The WST-8 assay is based on the colorimetric reduction of water soluble tetrazolium (WST) by mitochondrial dehydrogenase
The absorbance of formazan dye solution is in direct proportion to the number of viable cells. Compared with the prevalent WST-1 method, the sensitivity of WST-8 assay is higher meanwhile the solubility and stability of formazan dye is better.
Fig. 3. Microscopy comparison of HeLa cells and DG44 cells transfected with L2K and Sinofection respectively. Transfections were performed following the manufacturer’s recommendations.
Fig. 4. Cytotoxicity comparison of Sinofection and L2K for 4 cell lines. Transfections were performed following the manufacturer’s recommendations.