Penetrantin

Penetrantin is a term that appears infrequently in scientific literature and does not have a widely recognized, standalone definition. In many contexts it is used as a misspelling or informal variant of penetratin, a well-known cell-penetrating peptide (CPP).

Penetratin (also called the Antennapedia peptide) is derived from the Antennapedia homeobox protein of Drosophila melanogaster and is used to promote cellular uptake of diverse cargoes. A common variant uses the sequence RQIKIWFQNRRMKWKK, though multiple variants exist. Penetratin can facilitate entry of small molecules, peptides, nucleic acids, and nanoparticle formulations into a range of cell types, and is used in basic research and some preclinical delivery studies. The exact mechanism of uptake is not fully settled and likely involves a combination of direct translocation across the lipid bilayer and endocytic pathways, influenced by cargo properties and experimental conditions.

Production and applications: Penetratin is synthesized by standard solid-phase synthesis. It is used to improve intracellular delivery in vitro and, with appropriate cargoes and formulations, has been explored for in vivo applications. Researchers study its advantages and limitations, including variable efficiency, potential endosomal entrapment, off-target uptake, and possible cytotoxicity or immunogenic concerns.

Notes: If the term penetrantin is encountered outside penetratin contexts, check sources for intended meaning, as it may refer to a different substance or be a typographical error.