Siegman S, Truong NF, Segura T. (2015). Encapsulation of PEGylated low-molecular-weight PEI polyplexes in hyaluronic acid hydrogels reduces aggregation. Acta Biomater. in Press, doi:10.1016/j.actbio.2015.09.020
Baranyi, L. et al. Rapid Generation of Stable Cell Lines Expressing High Levels of Erythropoietin, Factor VIII, and an Antihuman CD20 Antibody Using Lentiviral Vectors. Human Gene Therapy Methods 24, 214–227 (2013). doi:10.1089/hgtb.2013.002
Wulhfard, S., Baldi, L., Hacker, D. L. & Wurm, F. Valproic acid enhances recombinant mRNA and protein levels in transiently transfected Chinese hamster ovary cells. Journal of Biotechnology 148 , 128–132 (2010). doi:10.1016/j.jbiotec.2010.05.003
Thomas M, Lu JJ, Ge Q, Zhang C, Chen J, Klibanov AM. (2005). Full deacylation of polyethylenimine dramatically boosts its gene delivery efficiency and specificity to mouse lung. Proc Natl Acad Sci U S A. 102(16):5679-84.
Durocher, Y., Perret, S. & Kamen, A. High-level and high-throughput recombinant protein production by transient transfection of suspension-growing human 293-EBNA1 cells. Nucleic acids research 30 , E9 (2002). doi:10.1093/nar/30.2.e9
Store at room temperature
Transfection Reagent Preparation and Storage Recommendations
These guidelines are our recommendations based off research, testing, and customer feedback. There are alternative methods available, but we suggest following these recommendations for easy adoption and consistently high performance. These methods are adapted from Cold Spring Harbor Protocols, an excellent secondary resource for transient transfection literature.
Reagent Preparation (1 mg/mL)
Materials:
1.1g PEI 25K (kingmornCatalog# KE1075).
2.1L Milli-Q® water, water for injection (WFI), or comparable biological-grade water
3.12 M Hydrochloric Acid (HCl)
4.10 M Sodium Hydroxide (NaOH)
5.Disposable 0.1-0.2um PES vacuum sterile-filter.
6.Sterile HDPE or polypropylene storage vials for reagent aliquots.
Equipment
1.1L glass beaker
2.1L glass graduated cylinder
3.Calibrated pH meter
4.2 x disposable 1mL plastic pipettes
5.Stir plate
6.PTFE coated stir bar
7.Vacuum pump
Method:
1.Dispense 1g of PEI 25K into beaker and suspend in 900 mL of water.
2.Add stir bar and set stirring to produce a small vortex.
3.Add hydrochloric acid dropwise until pH is < 2.0.
4.Cover top of beaker and stir for up to 3 hours until powder fully dissolves.
5.Add sodium hydroxide dropwise until pH is 6.9-7.1.
6.Transfer solution to graduated cylinder and add water until the total volume is 1L.
7.Sterile-filter through vacuum membrane.
8.Aliquot as desired and store at -20℃.
Reagent Storage
Frozen aliquots can be stored at -20℃ for up to one year. Aliquots can be thawed and kept at 4℃ for up to two weeks, but should never be re-frozen.
References
1. Polyethylenimine (PEI), linear (1 mg/mL). Cold Spring Harbor Protocols 2008, pdb.rec11323– pdb.rec11323 (2008). doi:10.1101/pdb.rec11323