Bacteriophage Inactivation by Antiphage Serum Diluted in Distilled Water

Abstract

THE fraction ƒ of bacteriophages remaining active t minutes after having been mixed with antiphage serum may be expressed by the following relation¹: in which D represents the dilution of the serum. The rate constant k, therefore, is a measure of the potency of the serum. Usually, k is determined by diluting the serum and the suspension of virus particles in nutrient broth or buffered saline, in which media a good serum may, at 37° C, show a K-value of 500–1,000 per min. Hence, in order to reduce the fraction of surviving virus particles, ƒ, to less than 1 per cent within an hour, such a serum cannot be diluted by more than 10⁴.