Try this handy little recipe. It's not as strong as the commercially available preparations and will allow the workers to live long enough to feed the eggs so that the colony is destroyed and the problem is taken care of.1 qt. water (1.1litre)
1 cup sugar (250 ml.)
1 tblspn Boric Acid (5 ml.)
Boric Acid is available at drug stores and can also be use for first- aid. Use this liquid to soak a cotton-ball placed in a small (yogurt) container with holes to allow the ants in.
Check daily to make sure it is wet enough and doesn't dry out. The ants will take a week or so to disappear.
If they do re-appear, some eggs could have hatched and simply repeat a second time