This is where it gets interesting. The basic salt-saturated solution will cause the nicotine to separate at temperatures over 60C. So, just for fun take the temperature up to around 70C and you'll see the oil separate and rise to the top as a separate (very small)layer. This isn't pure nicotine, but includes all the alkaloids and some other contaminants. But it does give one a good idea what you're going to get.
Cool, filter out the solids, and extract twice with 30ml of naptha. Evaporate the naptha at room temperature and you have a small amount of relatively pure nicotine. There isn't enough here to do much with, so dissolve in acetone and save. Repeat the entire procedure saving the nicotine in acetone until you have enough to deal with. I use 4 of the full extractions to get enough nicotine to further purify