Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu Hair Loss Researchers: Study Design Comparison

Journal of Cosmetic Dermatology (2018) Randomized, vehicle-controlled, N=60 2% topical cream, twice daily 12 weeks Hair density (hairs/cm²) +31.2 hairs/cm² vs +3.1 control p<0.001 Gold-standard design with objective phototrichogram measurements. Results clinic

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  • Journal of Cosmetic Dermatology (2018)
  • Randomized, vehicle-controlled, N=60
  • 2% topical cream, twice daily
  • 12 weeks
  • Hair density (hairs/cm²)
  • +31.2 hairs/cm² vs +3.1 control
  • p<0.001
  • Gold-standard design with objective phototrichogram measurements. Results clinically meaningful
  • International Journal of Molecular Sciences (2019)
  • In vitro dermal papilla cell culture
  • 1–50 μM in culture medium
  • 72 hours
  • Cell proliferation (MTT assay)
  • 160% increase at 10 μM vs untreated
  • p<0.01
  • Mechanistic validation showing follicular cell response, but in vitro results don't predict clinical efficacy
  • Seoul National University (2020)
  • Liposomal stability study
  • 1% in liposomes vs aqueous solution
  • 6 months storage at 25°C
  • Peptide activity retention (HPLC)
  • 89% vs 31% remaining activity
  • Not applicable (stability study)
  • Critical formulation data. Demonstrates why delivery system determines real-world outcomes
  • Yonsei University (2021)
  • Microneedling + GHK-Cu penetration study
  • 2% topical, post-needling vs intact skin
  • Single application, 24h measurement
  • Dermal peptide concentration (LC-MS)
  • 340% increase with microneedling
  • p<0.005
  • Shows penetration enhancement is real but timing-dependent. Clinical translation requires protocol precision