摘要 |
Neomycin B or Neomycin C is separated from a mixture thereof by elution of a mixture of isomeric Neomycins B and C, adsorbed on a carboxylic acid ion exchange resin, with aqueous solutions of an alkaline pH of successively increasing concentration of alkali. A specified ion exchange resin is "Amberlite" IRC-50 (Registered Trade Mark) in the ammoniacal form and specified aqueous alkaline solutions are N/4 and N solutions of ammonium hydroxide. The separated Neomycins B and C may be further purified by successive precipitation from methanol or decolourisation by treatment with animal charcoal. |