What do you mean by sticky?
Do you mean they are sticky to touch or do they stick when you use them?
If its just sticky to the touch, then just clean them ie. cd cleaning fluid or furniture polish sprayed on a cloth, and then put your finger in the cloth and clean each key (or use keyboard wipes)
If its sticking when you use them, then don't go spraying any more liquid onto/into the keyboard. They might come ok after repeated use.