Can chromatography be used to test if sugar crystals are pure?
Gas chromatography for sure. Paper chromatography – maybe. It depends on the level of impurity you want to detect as paper (or thin layer chromatography – TLC – is not really very sensitive.) Liquid chromatography will, but it also depends on your detector as sugars don’t have chromophores and won’t respond to UV. If you want to use LC to test for sugar purity, you should use a light scattering or corona detector, and again, it depends on the levels of impurities you want to detect. If you want to merely perform an identification on the sugar, I would reccommend infrared spectroscopy. It’s easy, hardly any sample preparation, no method development, and you get results in seconds.
