The Physicochemical Characteristics and Purification of Slow-Reacting Substance of Anaphylaxis

A preparative high yield procedure for the purification of slow-reacting substance of anaphylaxis (SRS-A) was developed by gas chromatography, gas chromatography-mass spectrometry and high resolution mass spectrometry to determine the required steps and evaluate the final product. The purification procedure was based on consideration of: the stability of the ethanol extracted starting material; the efficiency of desalting by non-ionic chromatography; the removal of phospholipids by base hydrolysis; the extraction of contaminating hydrocarbons, steroids and lipids by silicic acid chromatography and the elimination of other contaminants on the basis of molecular size with Sephadex LH-20 gel filtration. The final product when analyzed by ultraviolet and infrared spectroscopy and high resolution mass spectrometry for the first time demonstrated significant differences between the active preparations and their controls. On a weight basis, this highly purified, acidic, low molecular weight chemical mediator was active at the nanogram level or less.