Relative Toxicity of Antiseptics on Bacteria and Tissues in Cultures. ∗

Abstract

Lambert, 1 Lambert and Meyer, 2 and German 3 believe that an ideal antiseptic is one which kills the bacteria without harming the tissue cells and they have accordingly devised methods of comparing the toxic effects of antiseptics upon bacteria and tissue cells in vitro.

Lambert after exposing fragments of connective tissue for several minutes to a saline suspension of Staphylococcus aureus transferred them into various concentrations of mercuric chloride, potassium mercuric iodide, potassium cyanide, Dakin's solution, iodine, phenol, tricresol, argyrol, hydrogen peroxide, glycerol, or alcohol. After one hour the fragments were transferred to physiological salt solution where they remained from a few minutes to half an hour until explanted. Although most of the antiseptics killed the tissue cells at concentrations that did not kill the bacteria, a good growth of cells was observed after exposure for one hour to a 1:2,000 iodine solution, a strength sufficient to sterilize the tissue completely in most instances.

Lambert and Meyer placed rabbit spleen fragments in a Staphylococcus aureus suspension for one minute, and then for 20 minutes in various concentrations of alcohol, iodine, mercuric chloride, mercurochrome, acriflavin, protargol, albargin, gentian violet, neo-salvarsan, or hexylresorcinol. The fragments were then washed twice in salt solution. The best results were obtained with iodine, mercuric chloride, and neosalvarsan. It is possible that in these cultures the cells may have come from the center of the explant where they were partially protected. In a second series they added the antiseptics directly to the culture medium. In these cultures higher dilutions were used, and neosalvarsan alone was less toxic for cells than bacteria, i. e. inhibiting bacteria in dilutions of 1:10,000 to 1:10,10 while cells were only slightly damaged by these dilutions. They concluded that iodine and mercuric chloride are nearer the ideal than some of the newer preparations.