I'm assuming the solvent is water. You're right that it's not specified in the abstract. "In vitro" means "in glass", but the actual meaning is in any non-livin

I'm assuming the solvent is water. You're right that it's not specified in the abstract. "In vitro" means "in glass", but the actual meaning is in any non-living container, no matter what it's made from, e.g. in a petri dish. If it's in a living organism it's "in vivo".