Practical physiological chemistry; a book designed for use in courses in practical physiological chemistry in schools of medicine and of science . the prod-uct after each addition by bringing it into contact with a drop of lead acetateon a filter paper. To the boiUng fluid add acetic acid (in the case of the extractof pigs spleen and other solutions containing guanine the acetic acid should bereplaced by dilute sulphuric) until the insoluble copper sulphide collects and filterthe hot fluid as quickly as possible. C. Treatment of the Filtrate from Pigs Spleen.—When the filtrate from thecopper s
Practical physiological chemistry; a book designed for use in courses in practical physiological chemistry in schools of medicine and of science . the prod-uct after each addition by bringing it into contact with a drop of lead acetateon a filter paper. To the boiUng fluid add acetic acid (in the case of the extractof pigs spleen and other solutions containing guanine the acetic acid should bereplaced by dilute sulphuric) until the insoluble copper sulphide collects and filterthe hot fluid as quickly as possible. C. Treatment of the Filtrate from Pigs Spleen.—When the filtrate from thecopper sulphide is cold make strongly alkaUne with ammonia and precipitate thepurine compounds with a sUght excess of ammoniacal silver nitrate. Filter, washthoroughly with cold water. Pierce the paper, wash the precipitate into a flaskwith boihng water and decompose the silver precipitate with hydrochloric enough acid has been added the silver chloride will settle as a heavy case-ous precipitate leaving clear interstitial fluid. Filter and heat the filtrate toboiling. Treat with an excess of ammonia (enough to make about 1-2 per cent).. Fig. 39.—Guanine Chloride.(Reproduced from crystals furnished by Professor Walter Jones.) Allow to cool and filter off the guanine which precipitates. Wash the guaninewith I per cent ammonia and then suspend it in a Uttle hot water and add a fewdrops of 20 per cent sulphuric acid to dissolve it. At the boihng point add a Uttleanimal charcoal, boil and filter. Make strongly alkaline with ammonia. Snowwhite guanine is precipitated. Dissolve the precipitate in 20 volumes of boiling 5 per cent hydrochloric acid. Upon cooUng beautiful needle-shaped crystals ofguanine chloride separate. (See Fig. 39.) Evaporate the filtrate from the guanine to dryness on the water-bath to expelammonia. Moisten with hydrochloric acid and again evaporate. Treat theresidue with warm water. Does it dissolve almost completely indicating theabsence of xanthine and ur
Size: 1581px × 1581px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectbiochem, bookyear1916
