STERILIZATION 29 



Such antiseptic value, freedom from irritation and a low toxicity tend to make it 

 valuable. Lysol and liquor cresolis compositus (U.S. P.) are preparations of 

 this chemical in a neutral soap, which when dissolved in water form a clear or 

 slightly opalescent liquid. Creolin is a similar preparation with a resin soap, 

 forming, however, a turbid emulsion with water. 



There are numerous other coal-tar disinfectants, which are more germicidal 

 than phenol. They are valuable deodorants by destroying the putrefactive 

 bacteria producing such odors. They are less toxic, not readily affected by 

 organic matter and much cheaper if we compare their relative cost and disin- 

 fectant coefficient with that of phenol. 



Formaldehyde is used principally as a gaseous disinfectant. A solution of 

 the gas in water (liquor formaldehydi, U.S. P.) when used as a liquid disinfectant 

 is inferior to phenol or any of the coal-tar products. 



lodoform in itself is a very weak antiseptic, but when applied to wounds, the 

 organic matter present effects the liberation of iodine, which results in bac- 

 tericidal action. 



When certain dyes were discovered to possess a specific staining effect for 

 bacteria, numerous attempts were made to use them as germicidal or antiseptic 

 agents. Drigalski and Conradi observed the inhibitory effect that crystal violet 

 possessed upon the growth of the cocci, while this is also considered when in- 

 troducing gentian violet in the preparation of Petroff's media. The antiseptic 

 value displayed by brilliant green, crystal violet, and malachite green can be 

 observed in the chart on the following page, as published by Browning, Henaway, 

 Gulbrausen and Thornton. Experiments thus far performed led many to be- 

 lieve that the dyes possess a very low toxicity and at the same time a high anti- 

 septic value. 



Flavine, a substance belonging to the latter class, has recently been exten- 

 sively exploited by the above four co-workers, at the Bland-Sutton Institute of 

 the Middlesex Hospital in England, their original work having been published 

 in the British Medical Journal (No. 2925, Jan. 20, 1917). Flavine is a substance 

 belonging to the acridine group, being chemically the chloride of diamino- 

 methyl acridinum. It is a stable chemical, the solutions of which are not al- 

 tered at boiling temperature. 



" Flavine has been found to possess extremely powerful bactericidal and 

 antiseptic properties, which are enhanced rather than diminished by admixture 

 with serum. In this respect, flavine differs from all other antiseptics in common 

 use. 



2. In the presence of serum, flavine is the most potent bactericide of all those 

 investigated for both staphylococcus and B. coli and it is easily efficient for the 

 enterococcus and for anaerobes, such as B. cedematis maligni. 



3. Flavine, in its relation to its bactericidal power, is very much less detri- 

 mental to the process of phagocytosis and less harmful to the tissues than 

 the other substances; hence much higher effective concentrations can be em- 

 ployed without damaging the tissues or interfering with the natural defensive 

 mechanisms. 



