(Arg)9 peptide – Cell-penetrating peptide

(Arg)9 is an cell-penetrating peptide made up of 9 arginine residues capable of traversing plasma membranes. It has been shown that Arg9 destabilize and disrupt the phospholipid bilayer allowing flow of ions across the membrane. (Arg)9 peptide plays an important role in efficient cellular uptake. The guanidinium group is a critical structural determinant for tight and rapid interactions with cell membrane. The cationic guanidinium group can form electrostatic interactions with anionic cell membranes components such as phospholipids and sulphated proteoglycans. This interaction can trigger the activation of specific intracellular signalling and cell internalization via various pathways. (Arg)9 peptide is used to deliver a variety of functionally active cargos such as peptides, small interfering RNA, oligonucleotides, plasmid DNA and liposomes into mammalian cells and plant cells with high translocation efficiency. (Arg)9 peptide can also be used to form chemical linkages with the cargo and act as a carrier peptide. It’s a Click (Arg)9.


Technical specification

(Arg)9 peptide buy Sequence : RRRRRRRRR
(Arg)9 peptide synthesis MW : 1 423.72 Da (C54H110N36O10)
(Arg)9 peptide price Purity : > 95%
Peptide Library synthesis service Counter-Ion : TFA Salts (see option TFA removal)
Peptide library synthesis Arg(9) peptide Delivery format : Freeze dried in propylene 2mL microtubes
buy synthesized peptides Other names : 143413-47-2, Arg(9) peptide, nona-D-arginine, nona-L-arginine, nonaarginine
peptide solubility guidelines Peptide Solubility Guideline
buy peptide price Bulk peptide quantities available


Peptide Product catalog 1 Size 1 Price 1 € HT Product catalog 2 Size 2 Price 2 € HT
(Arg)9 peptide SB019-1MG 1 mg 88 SB019-5*1MG 5×1 mg 308
FAM-(Arg)9 SB020-1MG 1 mg 198 SB020-5*1MG 5×1 mg 693
Alcyne-(Arg)9 SB021-1MG 1 mg 220 SB021-5*1MG 5×1 mg 770



1- Hu Y, Qiao C, Lv M, et al. BMC Res Notes. (2012)
(Arg)9 references Arg9 facilitates the translocation and downstream signal inhibition of an anti-HER2 single chain antibody



HER2 plays a critical role in the pathogenesis of many cancers and is linked to poor prognosis or cancer metastases. Monoclonal antibodies, such as Herceptin against HER2-overexpressing cancers, have showed satisfactory clinical therapeutic effect. However, they have difficulty to surmount obstacles to enter cells or blood–brain barrier.


In this study, a cell-penetrating peptide Arg9 was linked to the C-terminus of anti-HER2 single chain antibody (MIL5scFv). Flow cytometry, confocal microscopy and electron microscopy analysis all revealed that Arg9 peptide facilitated the penetration of MIL5scFv into HER2-negative cell line NIH3T3 and orientate in mitochondria. More interestingly, Western blot assay showed the potential enhanced bioactivity of MIL5scFv-Arg9 in HER2+ cell line SKOV3, indicating that Arg9 could help large molecules (e.g. antibody) to penetrate into cells and therefore enhance its anti-neoplastic function.


Our work represented an attractive by preliminary strategy to enhance the therapeutic effect of existing antibodies by entering cells easier, or more desirable, surmounting the physical barriers, especially in hard-to-reach cancers such as brain metastases cases.

2- He D, Yang H, Lin Q, Huang H. Int J Biochem Cell Biol. (2005)
(Arg)9 references Arg9-peptide Facilitates the Internalization of an anti-CEA Immunotoxin and Potentiates Its Specific Cytotoxicity to Target Cells


Arginines-containing membrane translocational signals (MTS), such as Tat(47-57) and VP22(267-300), and synthetic arginine-rich peptides have been reported to be efficient carriers for transporting various types of biomolecules into cytoplasmic and nuclear compartments of living cells. Among those arginines-containing MTS, a 9-mer arginine peptide (Arg9) was proved the most economical and efficient. We fused Arg9-peptide to an anti-CEA (Carcinoembryonic antigen) immunotoxin, PE35/CEA(Fv)/KDEL, at the position between the toxin moiety and the binding moiety. Strong binding and internalization of this fusion protein was observed in all detected cell lines, but little cytotoxicity to the cells that lack the CEA molecules on the cell surface was detected. However, the cytotoxicity besides the binding activity of the fusion protein to specific tumor cells expressing large amount of CEA molecules on the cell surface was improved markedly, indicating that the Arg9-peptide is capable of facilitating the receptor-mediated endocytosis of this immunotoxin, which leads to the increase of the specific cytotoxicity of this immunotoxin.