If you are also attempting to go for the Tonic collector achievement then it is really imporant that you manage your ADAM resources.
Try not to purchase Health, Eve or Plasmid upgrades until later on in the game or preferably until you have this achievement. Unless you are playing on Hard then you won't need to anyway.
To earn this achievement you must purchase All 16 slots which will cost a total of 1360 Adam.
If you rescue EVERY little Sister in the game you will earn a max of 3080 ADAM if you harvest you will earn 3360.
If you are upgrading your plasmids focus only on 1 or 2 rather than upgrading them all or you will run out of Adam. I would recommend not upgrading any plasmids until later in the game as sometimes there cost reduces. eg Electro Bolt 2 cost 120 Adam in Arcadia but when I reached Hephaestus it was down to just 20 Adam and all of the other Plasmids were massively discounted. So hold off and invest wisely.