Viral Packaging


If I want to make my own viral particles, which format should I purchase?
Sigma offers ready-to-use viral particles (200 µl at 1 x 106 TU/ml) to eliminate these steps for you. However, if you choose to make your own viral particles, we recommend the purified plasmid format for packaging protocols that require less than 1µg of plasmid DNA (i.e. typical protocols for 60 mm dishes utilize 1µg of transfer vector and yield 4-5 ml of viral particles). For large scale production of viral particles, we recommend the bacterial glycerol stocks. The bacterial format allows for propagation of the shRNA transfer vector and facilitates larger scale DNA purification required for scaled up packaging co-transfections.

Do you offer custom viral production services for larger volumes of viral particles?
If you need more than 200 µl of lentiviral particles (currently provided), we can discuss custom production on a larger scale. Another solution may be to purchase the bacterial stocks or plasmid DNA and perform the packaging steps in your facility. Please contact your local sales representative or e-mail us at

Which packaging systems are compatible with pLKO.1 shRNA vectors?
The MISSION TRC shRNAs are cloned into the pLKO.1 transfer vector that is compatible with standard 2 plasmid (packaging vector with rev gene and envelope vector) or 3 plasmid (packaging vector without rev gene, envelope vector, and rev expression vector) packaging systems.

Do you offer any cells for packaging?
No, we do not currently offer packaging cells. We recommend the commonly available engineered cell line HEK 293T. It is imperative that the cells you use be healthy, never grown to confluency, etc. for the best viral titers.

Contact Us
For questions about the library, pricing and quotes or other concerns, please e-mail us at:

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