DIY peptide stacking claims on TikTok: what's real?

What did @diyqueen81 actually say?

The creator walked viewers through mixing a powdered peptide, which she called "GHQ" but almost certainly meant GHK-Cu (copper peptide GHK-Cu), into a bottle of The Ordinary's Hyaluronic Acid 2% + B5 serum. The method involved scraping the powder from a vial, dissolving it in a dropper of serum, waiting about ten minutes, then pouring the rest of the bottle in and storing it in the fridge. She described the dissolved product turning "a really pretty blue color" and presented the result as a ready-to-use peptide serum.

No source for the peptide was mentioned, no purity testing was referenced, and no concentration was calculated. The video frames this as a simple DIY cosmetic swap, which understates the real variables involved significantly.

Does the science back this up?

GHK-Cu does have a real evidence base for topical use, which separates it from many peptides flooding social media. But the method shown here skips nearly every step that determines whether it actually works.

GHK-Cu (glycyl-L-histidyl-L-lysine copper complex) has been studied for collagen synthesis stimulation, wound healing support, and antioxidant activity in skin. Pickart and Margolina (2018, Biomolecules) reviewed decades of research showing GHK-Cu can upregulate collagen and glycosaminoglycan production in fibroblasts at concentrations typically between 1 and 10 nanomolar in cell studies. Leyden et al. (2018, Journal of Cosmetic Dermatology) found modest but real improvements in skin firmness and fine lines in human subjects using formulated GHK-Cu products.

The problem is that none of those studies used powder scraped from an unmarked vial and dissolved into a random volume of hyaluronic acid serum. Peptide stability, pH compatibility, preservative interaction, and final concentration all matter. The blue color the creator mentions is consistent with the copper complex forming, which is at least a soft sign the peptide is present, but color alone does not confirm purity, concentration, or stability.

What did they get wrong (or right)?

Credit where it is due: refrigerating the finished product is correct. GHK-Cu degrades faster at room temperature, and cold storage extends usable life. Pickart's own formulation guidance consistently recommends refrigeration for copper peptide products. That part of the advice is sound.

What is genuinely problematic: the creator never identifies where the peptide powder came from. Research-grade GHK-Cu from a reputable supplier is not the same thing as powder purchased from an unverified online vendor. Without third-party certificate of analysis, you have no confirmation of identity, purity, or sterility. The FDA does not regulate peptide powders sold as "research chemicals," which is how most of these products are marketed to get around oversight.

The mixing method also raises formulation concerns. The Ordinary's HA + B5 serum has a pH of approximately 6 to 7. GHK-Cu stability has been documented to be pH-sensitive, with degradation accelerating outside of optimal ranges. Dissolving peptide into an existing commercial formula with preservatives already calibrated for a specific product is not equivalent to a purpose-built formulation. The creator presents this as simple and safe. It is neither simple nor well-characterized.

Calling it "GHQ" throughout also suggests limited familiarity with the compound, which is a reasonable red flag for viewers trying to assess credibility.

What should you actually know?

GHK-Cu is one of the more legitimate peptides in the skincare space. It is not a fantasy ingredient. But DIY reconstitution from powder into an off-the-shelf serum is a different category of intervention than buying a tested, formulated product, and that gap matters.

If you want to use GHK-Cu topically, commercially formulated products from brands that publish their concentration and stability data are a safer starting point than mixing your own. Researchers studying GHK-Cu use precise nanomolar concentrations in pH-controlled vehicles. The DIY version shown here has no reliable way to achieve that.

There is also a sourcing question that cannot be ignored. Peptide powders sold online for "research use" are not subject to the same manufacturing standards as pharmaceutical or even cosmetic ingredients. Contamination, mislabeling, and incorrect purity are documented problems in this supply chain. A 2021 analysis by Cohen et al. (JAMA Internal Medicine) of research peptides purchased online found significant discrepancies between labeled and actual content across product categories.

Bottom line: the science behind GHK-Cu is real. This particular method of using it is not supported by that science.