R9
Nona-arginine
RRRRRRRRR Amino Acids · MW: 1423.8
Amino Acids
RRRRRRRRR
Molecular Weight
1423.8
Half-life
minutes; often prolonged by cargo conjugation
Research Score
4.3
Studies
87
Storage
Store lyophilized at -20°C, reconstituted at 2-8°C
What is R9?
R9 is a homopolyarginine CPP made of nine D- or L-arginine residues, most commonly used in the L-form for delivery research. It is a standard benchmark peptide for intracellular uptake of cargo across many cell types.
Key Benefits & Mechanisms
simple synthesis
strong cationic uptake
useful benchmark carrier
Research Summary
Polyarginine peptides are among the most reproduced CPPs for delivering proteins, peptides, siRNA, and nanoparticles, with uptake driven by arginine-rich interactions with cell membranes.
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