The essentials of chemical physiology for the use of students / by W.D. Halliburton.

  • Halliburton, W. D. (William Dobinson), 1860-1931.
Date:
1919
Catalogue details

Licence: In copyright

Credit: The essentials of chemical physiology for the use of students / by W.D. Halliburton. Source: Wellcome Collection.

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    The best reducing agent to employ in the foregoing tests is sodium hydrosulphite (see p. 135), except in the case of methsemoglobin ; here warming with ammonium sulphide is the best. (b) Dry: boil with glacial acetic acid and a crystal of sodium chloride on a glass slide under a cover glass. When cold, haemin crystals are seen. (c) Try guaiacum test and Adler’s test (p. 135). (d) If the blood is old and dry, and its haemoglobin converted into haematin : i. Try haemin test. ii. Try guaiacum test and Adler’s test. iii. Dissolve it in potash : add reducing agent, and examine for spectrum of reduced haematin. 11. If bile is suspected : (a) Try Gmelin’s test for bile pigments (see p. 108); also Cole’s test (p. 212). (A) Try Pettenkofer’s and also Hay’s tests for bile salts (see p. 108). 12. Miscellaneous substances. (a) Mucin. Precipitated by acetic acid or by alcohol. The precipitate is soluble in lime water. By collecting the precipitate and boiling it with 25 per-cent, sulphuric acid a reducing sugar-like substance is obtained. Mucin gives the protein colour tests. (A) Nucleo-protein. Precipitated by acetic acid or by alcohol. The precipitate is often viscous. It is soluble in dilute alkalis such as 1 per-cent, sodium carbonate. This solution causes intravascular clotting. If the pre¬ cipitate is collected and subjected to gastric digestion, an insoluble deposit of nuclein is left, which is rich in phosphorus. Nucleo-protein gives the protein colour tests. (c) Gelatin. This also gives some of the protein colour tests, but not those of Millon or Adamkiewicz. It is not coagulated, but dissolved in hot water. The solution gelatinises when cold. (d) Urea. Very soluble in water. The solution effervesces when sodium hypobromite or fuming nitric acid is added. Concentrate a fresh portion, add nitric acid, and examine for crystals of urea nitrate. Solid urea heated in a dry test-tube gives off'ammonia, and the residue is called biuret, which gives a rose-red colour with copper sulphate and caustic potash. (e) Uric acid. Very insoluble in water; soluble in potash, and precipi¬ tated from this solution in crystals by hydrochloric acid. Uric acid crystals from human urine are deeply pigmented red. Try murexide, Folin’s and Schiff’s tests (see p. 196). (/) Cholesterol. Characteristic Hat crystalline plates. For various colour tests see pp. 108, 109. 13. Urine. Normal constituents. (a) Chlorides. Acidulate with nitric acid; add silver nitrate; white precipitate. (/>) Sulphates. Acidulate with nitric acid or hydrochloric acid: add barium chloride; white precipitate. (c) Phosphates. Acidulate frith nitric acid; add ammonium molybdate;