How can I get Dr. Dupliscidus to give me the antidote?

Hint 1 of 7:

As long as he can deny the existence of the antidote, there's no way you can
get it.

Hint 2 of 7:

You're going to have to find evidence that the antidote exists.

Hint 3 of 7:

Search the lab.

Hint 4 of 7:

Look at the blackboards.

Hint 5 of 7:

They can slide.

Hint 6 of 7:

In particular, slide the board on the left-hand side of the set of boards on
the right.

Hint 7 of 7:

Look at it, and you'll see the formula for the antidote.