Electricity, employed in the form of continuous electrolytic currents passing through a solution of venom, destroys the toxicity of the latter, because under these conditions there is always formed, at the expense of the salts accompanying the venom, a sufficient quantity of chlorinated products (hypochlorites, chlorates, &c.), and a small amount of ozone, the oxidizing action of which is extremely powerful.
With alternating currents of high frequency, Phisalix, repeating the experiments that Arsonval and Charrin had performed upon diphtheria toxin, thought that he had succeeded in attenuating venom to the point of transforming it into vaccine.[11] But it has been shown by Marmier that this attenuation was simply the result of thermic actions. When, by means of a suitable arrangement, any rise of temperature was carefully avoided, no modification of toxicity was obtained.[12]
The influence of light, which has no effect upon venom preserved in a dry state, is, on the contrary, very marked upon venom in solution. Solutions of venom that are destined for physiological experiments should therefore not be employed without controls, if they be several days old. Apart from the fact that, if care be not taken to render them aseptic, they very soon become contaminated with the germs of all kinds of microbes, it is found that they gradually lose a large part of their activity, especially when they remain in contact with the air. By filtering them through a Chamberland candle and keeping them in the dark, in a refrigerator, in perfectly closed phials, they may be kept unimpaired for several months.
The addition of glycerine in equal parts to a concentrated solution of venom is also an excellent means of preservation.
Phisalix has shown that the emanations from radium attenuate and then destroy the virulence of Cobra- and also of Viper-venom.
“Dry Viper-venom, dissolved in aqua chloroformi in the proportion of 1 in 1,000, is put up in four tubes, three of which are irradiated, the first for six hours, the second for twenty hours, and the third for thirty-six hours. Three guinea-pigs, of equal weight, are inoculated with equal quantities of the irradiated venom; a control receives the non-irradiated venom. The latter dies in ten hours; the animal inoculated from the first tube dies in twelve hours; the one inoculated from the second tube in twenty hours, and the third proves resistant without any symptom of poisoning. A second inoculation produces a transitory lowering of the animal’s temperature by half a degree. At the end of four days it dies after inoculation with a lethal dose.”
The nature of the solvent exerts a great influence upon the action of the emanations from radium: if the same experiment be performed with venom dissolved in a 50 per cent. mixture of glycerine and water, the attenuation is merely relative after six hours.