The literature on the concentration and purification of diphtherial toxin and toxoid, as reviewed by Smith (1932), and Leonard and Holm (1933), shows a long list of agents that have been used for these purposes. Both publications agreed that the best yields as well as superior immunizing values were obtained with toxoids precipitated with alum.
Roux and Yersin (1889) used aluminum salts to precipitate toxin from solution. However, the enhanced antigenicity of alum toxoid was first demonstrated by Glenny, Pope, Waddington and Wallace (1926), who showed that unwashed and undissolved alum-precipitated diphtherial toxoid was superior to crude toxoid in the immunization of guinea-pigs and rabbits.
Glenny and Barr (1931), and Wells, Graham and Havens (1932), found that the optimal amount of alum required for complete precipitation, with the least amount of extraneous material in the precipitate, differed with the various types of media used in the production of the toxin.
A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the University of Pennsylvania.