Liposome-Delivered GHK-Cu Peptide Inhibits Nearly Half of Skin-Degrading Elastase Activity

Liposomes were prepared using the thin-film hydration method combined with freeze-thaw cycles and extrusion. Both anionic and cationic formulations were tested with varying lipid content, composition, and GHK-Cu concentrations. Physicochemical properties (size, stability, bilayer fluidity) and peptide encapsulation efficiency were characterized. In vitro enzyme inhibition assays measured tyrosinase and elastase activity.

GHK-Cu is one of the most studied cosmetic peptides, with evidence for stimulating collagen production, wound healing, and anti-aging effects. However, its effectiveness depends on reaching the right skin layers. This study demonstrates that liposome encapsulation can deliver GHK-Cu while preserving its biological activity, and the strong elastase inhibition (49%) provides a specific mechanism for its anti-aging effects — protecting the elastin network that keeps skin firm and resilient.

Peptide delivery is one of the major challenges in both pharmaceutical and cosmetic applications. Liposomes offer a solution by protecting peptides from degradation while enhancing skin penetration. This study contributes to the growing field of peptide-loaded nanocarriers for skincare, demonstrating that carefully designed delivery systems can maintain peptide bioactivity. As consumer demand for science-backed cosmetic peptides grows, delivery technology will be a key differentiator.

This is entirely an in vitro formulation study — no skin penetration tests, cell culture viability assays, or clinical testing was performed. The 31.7% encapsulation efficiency means most of the GHK-Cu is not captured by the liposomes. The liposome stability over time during storage was not fully characterized. The elastase and tyrosinase assays are simplified models that may not fully represent skin biology. No comparison to free (unencapsulated) GHK-Cu was described in the abstract.