B-27 Supplement is a serum-free supplement which is used for the growth and short or long term excitation of hippocampal neurons and other neuronal cells from central nervous system. B-27 supplement is a 50X liquid that is suitable for the cultivation of most neuronal cells. This product is a Vitamin A free, B27 supplement. Without Vitamin A, this supplement can be used to prevent the differentiation of stem cells to neuronal cells.