PSP is just protein hydrolysate, nothing like a growth factor and Biopelle probably calls their peptides growth factors. It’s marketing, no more! I did work with several real growth factors in in vitro assays using cancer cell lines and fresh human blood and we also sell growth factors, growth hormones, and similar proteins (on prescription only) at the pharmacy. These are all very expensive and very unstable. Putting those into a cream or serum will have them fully degraded/inactivated before the bottle is fully packed. And even if, they do not penetrate skin and topical application does only deplete your money purse.
@Pharma - I think the hope is that they will break down before getting to the consumer. That way they are not producing illegal drugs but still get the marketing story benefit of the ingredients. Pretty standard cosmetic marketing.
EGF is a 6 kDa protein. It will never cross the epidermis to reach the basal proliferative layer.
Scammers, probably; or a very careful marketing campaign to avoid making drug claims (which means that it doesn’t work, because if it would, then it will be a drug).
Even what some snake oil purveyors say, that it initiates a cascade of signaling within the epidermis, is just a smoke screen. Signalling and protein synthesis is required in the corneocytes to produce that cascade before you reach the keratinocytes.
Small problem… the corneocytes have lost all their genetic information and cellular machinery that allows a cell to produce protein, enzymes, and initiate metabolic processes, so that can’t happen.
EGF (for research and pharma purposes) is ship as lyophilisate at -20°C. Once diluted with water/culture medium, it will be active for a few days the most. If you buy a liquid with EGF and it comes at room temp, it will be toast long before it even got to the delivery service.
There are some proteins which can be kept in the fridge for a few weeks or even months but these require stabilisation through precipitation or crystallisation in speciality buffers (such as insulin, one of the rare +/- stable exception).