We've had researchers ordering this for mitochondrial studies who then switch to cosmetic formulation work, and they all seem to settle on the 500mg vials for easier handling—basically, the smaller size avoids waste when you're only running a few assays at a time.
It's a with a molecular weight of 663.43 g/mol, and the purity is >99% by HPLC, which matters because even trace impurities can shift in cell work, and CAS is 53-84-9 if you need to cross-check with your lab's inventory system.
Most buyers go with the 1000mg for topical formulations since you're dissolving it in water anyway, but it's not suited for oral supplementation without additonal buffering (check your local regulations on that), and teh shelf life is 24 months stored cool and dry, though we usually have stock and can ship within a week or so.
500mg or 1000mg vials, MOQ is typically 10 units, and we include a COA with every batch.