We're actually speaking about a tenth of a millionth of a liter of compound, but we can dilute that compound several thousand times in its own volume of water and then test it against a whole range of nasty stuff, like cancer cells or bacteria.
Una décima de millonésima de litro, diluimos el compuesto unas miles de veces, en su propio volumen de agua y lo probamos contra muchas cosas malas, como células cancerígenas o bacterias.