N2 Supplement is a serum-free, chemically defined 100X supplement based on Bottenstein’s N2 formulation(1). It is recommended for the growth and expression of neuroblastomas and for the survival and expression of post-mitotic neurons in primary cultures from both the peripheral nervous system (PNS) and the central nervous system (CNS). It can be used as a substitute for the N-1 Bottenstein formulation. N-2 medium appears to be selective for neuronal cell lines and does not support the growth of nonneuronal cell lines.