Lipsomal C is a form of C that is encapsulated - sometimes with non Genetically-Modified-Organisms soy lechithin (& soy lecithin does not hurt the thyroid like regular soy) - so that, unlike regular oral C, it does not get lost in the GI tract but can get through to the liver where it is needed.
You can make your own liposomal C, lot of info on that on the net & on Youtube in particular. Easy & cheap & it has worked great for me, though I drink the whole 1 1/2 cup formula every day.