Handbook for the bio-chemical laboratory / By John A. Mandel.

  • Mandel, John Alfred, 1865-1929.
Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: Handbook for the bio-chemical laboratory / By John A. Mandel. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

    67/120 (page 55)
    with 1 to 2 c.c. concentrated alcoholic solution of acid-free zinc chloride. After a few days yellow crystals of creatinin zinc chloride separate out ; these are filtered off, washed with alcohol, dissolved in hot water and decomposed by boiling for about half an hour with an excess of freshly precipitated lead oxide or lead carbonate. Filter while hot, decolorize the filtrate by boiling with animal charcoal, filter again, evaporate to dryness, and extract the residue by strong alcohol in the cold, which removes the creatinin. Creatin remains behind undissolved. 3. Precipitate -§- to 1 litre of urine with phospho-tungstic acid and hydrochloric acid, filter, and treat the precipitate with caustic baryta. Filter, and remove the excess of baryta by means of carbon dioxide, and filter again. Evaporate the filtrate to dryness, extract the residue with strong alcohol and evaporate the alcohol, when the creatinin will be obtained impure. It may be purified as above described. Properties.—Creatinin crystallizes in long, colorless, highly refractive, monoclinic prisms, which do not become white with loss of water when heated to 100° C. It dissolves in 11.5 parts cold water and 100 parts cold alcohol, though it is more soluble in hot liquids. It is nearly insoluble in ether. Creatinin combines with HC1 and certain metallic salts, form- ing crystalline compounds. Creatinin acts as a reducing agent, reducing Fehling's and Trommer's solutions; also reducing mercuric oxide to metallic mercury, and yielding oxalic acid and methyl guanidin. Xanthin Bases. Xanthln, C&H4N402. Hypoxanthin, C.IO^O. ' 5 4 4 Adenin, C5H6N6. Guanin, C5H5N50. Preparation.—250 grms. finely chopped beef liver is placed