Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu Complexion Protocol: Application Methods Comparison

Direct topical (dropper to cleansed skin) Stratum corneum + upper dermis (0.1–0.3mm) 90 seconds post-refrigeration removal Daily (AM or PM) Highest bioavailability for at-home use. Minimises oxidation exposure Mixed into serum base (pre-formulated) Variable. D

This source-based comparison does not add ratings or recommend a winner.

  • Direct topical (dropper to cleansed skin)
  • Stratum corneum + upper dermis (0.1–0.3mm)
  • 90 seconds post-refrigeration removal
  • Daily (AM or PM)
  • Highest bioavailability for at-home use. Minimises oxidation exposure
  • Mixed into serum base (pre-formulated)
  • Variable. Depends on carrier pH and viscosity
  • 7–14 days if stored at 4°C
  • Daily
  • Convenient but sacrifices freshness. Copper chelation declines in mixed formulations
  • Microneedling pre-treatment
  • Deep dermis (0.5–1.5mm with 0.5mm needle depth)
  • Same 90-second rule applies
  • Weekly maximum
  • Maximal penetration but requires sterile technique. Infection risk if protocol breached
  • Occlusive patch delivery
  • Sustained dermal contact (4–8 hours)
  • Requires anhydrous formulation to prevent degradation
  • 2–3x weekly
  • Extends contact time but risks oxidation in non-refrigerated environment