What it is
sh-Polypeptide-121 is a synthetic human-identical polypeptide produced through recombinant biotechnology, where the sh prefix indicates a synthetic version of a human protein sequence. In cosmetics it is used as a skin-conditioning ingredient in serums, creams, and similar products. It is a supporting peptide ingredient and does not function as a UV filter.
Safety & warnings
Bioengineered polypeptides of this type are generally well tolerated at the low levels used in cosmetics. Irritation or sensitization is uncommon but possible, and the raw material may contain stabilizers or preservatives that contribute to reactions.
Origin & sourcing
Synthetic; manufactured by recombinant biotechnology (typically microbial fermentation) to produce a peptide matching a human protein sequence rather than being extracted from human tissue.
Questions everyone asks
What is sh-Polypeptide-121?
It is a synthetic, bioengineered polypeptide used as a skin-conditioning ingredient. The sh prefix means it is a synthetic version of a human protein sequence made by biotechnology.
Is it a sunscreen active?
No. It is a supporting skin-conditioning peptide and provides no UV protection on its own.