742 CHEMISTRY OF TOXIN AND ANTITOXIN 



stance which corresponds to it in spatial dimensions. In the biological process adsorbent and 

 adsorbed substance are causally connected in the manner of their formation, so that their 

 shape may very well be fitted to one another. In the laboratory it has not yet been possible 

 to produce an adsorbed substance from an adsorbent which, in consequence of the mode of 

 formation, has a particular spatial arrangement and is preferentially adsorbed.' 



The adsorption reactions have been useful in the purification of toxin and anti- 

 toxin. Rakusin and Flieher^ were able to remove 44 per cent of the unessential pro- 

 teins from antitoxic diphtheria plasma by the use of dry aluminium oxide. In this 

 case the antitoxin was not adsorbed but was in the filtrate. Botulinum toxin, on the 

 other hand, was adsorbed by this reagent, and by this means Sommer, Sommer, and 

 Meyer^ were able to obtain a highly potent toxin. That adsorption reactions of 

 immune bodies with inorganic colloids or other immune bodies are not always smooth- 

 ly reversible has been explained on the ground that denaturation, involving chemical 

 changes in the protein molecule, takes place when it is discharged by contact with a 

 colloid bearing an opposite charge.'' 



Calmette and Massol^ were the first to measure the antitoxic value of a serum by 

 the precipitate which is formed when the serum and its homologous toxin are mixed. 

 While this in vitro method of standardization, as perfected by Ramon,** Glenny, and 

 others and later by Bayne- Jones,' has been of very great practical value, it is not yet 

 definitely established that the fiocculation is produced exclusively by the toxin and 

 antitoxin.^ 



THE CATAPHORESIS OF TOXIN AND ANTITOXIN SOLUTIONS 



In 1907 Field and Teague"* published results of experiments which indicated 

 that toxin and antitoxin migrated to the cathode whether the reaction of the toxin 

 and the antitoxin solution was alkaline or acidic. They concluded that toxin and 

 antitoxin were, therefore, not amphoteric proteins, and that the neutralization of 

 toxin by antitoxin was not a chemical reaction since both bore the same charge. 

 Field and Teague used 2 per cent agar arcs as bridges connecting the toxin or anti- 

 toxin solutions with the distilled water into which platinum-coil electrodes were 

 dipped. After no volts direct current had been applied for from four to six hours, 

 the agar was pushed out of the glass supporting arcs and the toxin or antitoxin was 

 extracted from the agar with water. 



Bechhold'" in discussing the work of these authors could find no fault with their 

 experiment, but criticized at length their deductions. His own attempt to determine 



' Freundlich, H.: Colloid and Capillary Chemistry, p. 538. 1922. 



^Rakusin, M. A., and Flieher, G. D.: Ztschr.f. Immitnitdtsjorsch. u. exper. Therap., 3g, 193. 

 1924. 



3 Sommer, E. W., Sommer, H., and Meyer, K. F.: /. Infect. Dis., 39, 345. 1926. 



^ Samson, K.: Ztschr.f. d. ges. e.vper. Med., 49, 95. 1926. 



5 Calmette, A., and Massol, L.: Ann. de I'Inst. Pasteur, 23, 155. 1909. 



^ Ramon, G.: Compt. rend. Soc. de biol., 86, 711. 1922. 



' Bayne- Jones, S.: /. Immunol., g, 481. 1924. See also chap. Ivi, this volume. 



' Bronfenbrenner, J. J., and Reichert, P.: J. Exper. Med., 44, 553. 1926. 



' Field, C. W., and Teague, O.: ibid., 9, 86, 225. 1907. 



"Bechhold, H.: Mimchen. med. Wchnschr., 39, 192 1. 1907. 



