Tetrapeptide-21 Solution

A matrix peptide ready to pour

Tetrapeptide-21 is the GEKG sequence, a short peptide studied for its role in skin's support network and used in creams sold for a firmer, denser look. This liquid delivers it pre-dissolved in glycerin, butylene glycol and propanediol, so it can be metered straight into a batch without weighing tiny amounts of powder. It is part of our peptide solutions catalog.

INCI

Glycerin, Butylene Glycol, Water, Propanediol, Tetrapeptide-21, Ethylhexylglycerin, Benzoic Acid. The supplier lists the CAS as a mixture. The glycol-rich base also adds a humectant effect to the finished product.

Formulating guidance

Add it to the water phase or to a cooled emulsion below 40 °C. Keep the finished pH between roughly 4.5 and 7 and avoid strong oxidizers and long heating. It stays clear in gels and essences.

Product ideas and pairings

Firming serums, neck creams, eye contour gels and night creams are the usual homes. For a layered peptide serum it sits well next to Tripeptide-1 Solution and Palmitoyl Tripeptide-38 Solution, each added in turn with a clarity check. Keep claims on look and feel.

Packs and storage

Available in 0.28 oz (8 g), 1 oz (30 g), 2 oz (60 g) and 4 oz (120 g) bottles. Store closed, cool and away from light; refrigerate after opening.