However, those products were too concentrated and alkaline for use on wounds, as they strongly irritated healthy tissues.Almost a century later Carrel and Dakin observed that few doctors at the time practiced asepsis, and moreover there were no studies of the effectiveness of various antiseptics for wounds. They set out to look for a substance that did not irritate skin, yet had sufficient bactericidal power. Dakin tested more than 200 substances, measuring their action on tissues and bacteria. He found chloramines to be the best, for being stable, non-toxic, and not very irritating, yet powerful bactericides, presumably due to their release of hypochlorous acid. However, the difficulty of procuring them led him to choose "hypochlorite of soda" as a practical alternative.Between the two World Wars, the preparation was often called "Carrel–Dakin solution," even though Dakin did the bulk of the research work that led to its formulation. The name of Carrel was dropped after World War II, presumably due to his active involvement in eugenics movements and the advocacy of elimination of "inferior" humans.Since penicillin became established as an antibiotic in 1943, use of Dakins solution and other topical antiseptics for wound treatment has declined, and their use is frowned upon in modern medical care. However, the solution continues to be used (as of 2013) due to its broad activity against aerobic and anaerobic organisms, including fungi and antibiotic-resistant organisms, its very low cost, and its wide availability. In emergency situations, it can be produced on the field from liquid bleach and sodium bicarbonate.
Formulation
Dakins original solution contained sodium hypochlorite (0.4% to 0.5%), prepared by treating calcium hypochlorite with sodium carbonate ("washing soda"). The solution left after removal of the insoluble calcium carbonate still contained some soda. Boric acid (4%) was then added as a buffering agent to maintain a pH of between 9 and 10. Dakin found that alkalinity outside this range was too irritating. The solution, while unstable, remains effective for at least a week, if made to the correct pH.Other formulations have been developed over time. In 1916, Marcel Daufresne substituted sodium bicarbonate for Dakins boric acid as buffering agent. This formulation is the basis of current commercial products.The concentration chosen by Dakin (0.5%) was the maximum highest concentration found tolerable to the skin. It is the concentration recommended by the U.S. Center for Disease Control (CDC) as a household disinfectant. In one study, bactericidal effects of sodium hypochlorite solution were observed at concentrations as low as 0.025%, without any tissue toxicity in vivo or in vitro. It recommended that concentration be adopted as a "modified Dakins solution" for wound dressing. See also
Chlorine-releasing compound
Hydrogen peroxide
Povidone-iodine
Phenol ("carbolic acid")
Eusol


== References ==