Sure, but might end up on a slippery slope if you let any random person say "hey hospital, please treat me with that experimental drug; I give my informed consent and will pay you $100k for that".
That's why we usually put the burden of proof on the person conducting the experiment that there actually was informed consent. And you don't give informed consent by stating "I give informed consent", but by demonstrating that you understand the (potential) consequences, and then consenting to what you have demonstrated to understand.
