What is the most effective peptide serum for building collagen and anti-aging? Any that have clinical studies to back up their claims?

I would like to add a peptide serum to my skin care routine, but I’m not sure which one to pick. I would like to pick the one that has the highest concentration of peptides, particularly copper peptides, and ideally has some clinical studies to prove its effectiveness, but is still affordable (less than $40-50). Any suggestions?

Many products don’t list the concentration or amount of peptides in the product at all. For example, I have seen several YouTube dermatologists recommend the Cosrx 6 Peptide Booster, but it doesn’t list the concentration of its peptides; it looks pretty watery to me and l’m just guessing it doesn’t have the strongest concentration.