TfR-T12 TFA, a transferrin receptor (TfR)-binding peptide capable of crossing the blood-brain barrier (BBB), exhibits nanomolar (nM) binding affinity [1] [2].

TfR-T12, a synthetic peptide discovered through phage display, selectively binds to an alternative site on the transferrin receptor (TfR) distinct from transferrin's binding site. Once bound, it facilitates the internalization of the complex into cells expressing TfR [1]. Additionally, TfR-T12 can be covalently attached to a pegylated lipid, specifically 3-(N-succinimidyloxyglutaryl)aminopropyl-polyethyleneglycol(2000)-carbamyl distearoyl phosphatidylethanolamine (NHS-PEG2000-DSPE). This conjugation enables its use in the development of multifunctional lipid vesicles [2].