glutathione fat soluble Tri-Fortify® Liposomal GHK Cu serum

Improving glutathione production by engineered Pichia pastoris: strain construction and optimal precursor feeding | Applied Microbiology and Biotechnology | Springer Nature Link

In short, most animal products only contain B12 because the animals were given supplements and so are not a more natural source of this vitamin than if you take a supplement yourself

GHK Cu serum

Color:Blue / Silver - Velvet

Standard concentration: 2–4% Application amount: 3–6 drops per area, fingertip application Frequency: Once or twice daily — morning and/or evening Timing: After cleansing, before moisturizer Amount by area: Face: 3–5 drops Neck/décolletage: 5–8 drops Scalp (hair growth): 8–10 drops massaged in, leave on Injectable vs topical — which one do you actually need