The weight of the substance insoluble in the above solvents should be noted and reported. Analyze, qualitatively, the ash for inorganic constituents. ORGANIC CONSTITUENTS. * Treatment of the powdered drug with various solvents. III.-Five grammes of the finely powdered drug treat with chloroform in a continuous extraction apparatus for say six or eight hours. Evaporate the tincture and weigh the extract. (a) Treat the residue with water. Evaporate the aqueous washings on a water-bath to dryness, then heat to 100° C. in an air-bath. The loss may be calculated and recorded as volatile oil. (See "Summary," below.) (b) The extract is then treated with a small quantity of petroleum spirit and filtered. The filtrate is evaporated and the residue weighed. This product may be recorded as fixed oil. Describe the physical properties of this fixed oil. State whether it is easily saponified or not. The color reactions with the acids may also be stated. Reactions with other known oils may be studied in Maisch's "Materia Medica," p. 493, fifth edition, or Dragendorff's "Plant Analysis," pp. 101-105. (c) After treatment with petroleum spirit the filter and residue are macerated in 80 per cent. alcohol for about fourteen hours. Estimate the total extractive and record the same. Filter the solution and evaporate to a small bulk, which pour into a large volume of water slightly acidulated. If a resin precipitates collect it on counterbalanced filters, dry, and weigh. Examine the resin for solubility, etc. (See tests for Podophyllin and other resins of the U. S. P.) For further practical details in the various steps refer to Lyon's "Pharmaceutical Assaying," Dragendorff's "Plant Analysis," and Prescott's "Organic Analysis." (d) The chloroformic residue which now remains should be weighed. The physical properties (color, odor, taste, etc.) should be reported. IV. Dry the powder (dregs) which has been treated with chloroform and subject the same to the action of 80 per cent. alcohol for fourteen hours. Estimate the total extractive and report the same. (See "Summary," below.) (a) Evaporate the alcoholic extract on a water-bath to a small bulk. Pour into a large volume of water; collect, dry, weigh, and report upon any precipitated resin. (b) To the filtrate from (a) add a solution of neutral acetate of lead. Collect the precipitate, and on a tared filter wash repeatedly with small quantities of water, dry and weigh. Remove the precipitate from the filter, and burn in a porcelain crucible with a little nitrate of ammonium. The precipitate itself is next incinerated, and the whole finally ignited until the weight is constant. Deduct the weight of the residue from the weight of the precipitate, and the remainder may be noted as vegetable acids, etc., precipitated by lead. (See Dragendorff, pp. 39, 49, 69, 80. Also Fresenius, “Quantitative Analysis," American edition, 1881, p. 229 b.) (c) To an aliquot portion of the filtrate from (b) add a solution of subacetate of lead, filter and remove lead from solution by hydrochloric acid and hydrogen sulphide. The clear liquid is then neutralized and made up to a definite volume. This may be then examined for sugar by the wellknown Fehling's solution. This will give the quantity of sugar dissolved by alcohol. (d) Weigh and examine the undetermined extractive by using the remaining part of the filtrate from (b). This may contain alkaloid, coloring matter, etc. V.-Dry the residue (dregs) remaining after treatment with chloroform and alcohol, macerate for twelve hours in water; filter through paper; make up to definite volume, and exam ine a portion for the amount of extractive. The amount of extractive is computed and recorded. (a) 25 cc. of the solution is placed in a test tube and 50 cc. of absolute alcohol added; let stand in a cool place for twentyfour hours, allowing the gum to precipitate. This is collected on counterbalanced filters and weighed. The weight of same recorded. (See Summary below.) (b) The remaining extractive of this solution should then be estimated, and its weight recorded. It may contain albuminoid matter precipitated by tannic acid. VI. The residue (dregs) insoluble in chloroform, alcohol and water, is then treated with 500 cc. of water, to which 5 cc. of sulphuric acid (1.84 sp. gr.) has been added and boiled on a wire gauze support for six hours; fresh portions of water are added to keep the volume to about 500 cc. The extractive matter of this solution is examined and the weight recorded. (a) The acid of the solution is neutralized with potassium hydrate and the liquid brought to the boiling point. A precipitate may fall. Note its color and other physical characteristics. Filter off the precipitate; dry and weigh. (b) The clear solution from (a) is estimated for sugar. The result of which multiplied by 0.9 gives the amount of starch and allied substances. Estimate the weight of these constituents, and report same. VII. The remainder of the drug (residue) treat with 500 cc. of a two per cent. solution of sodium hydrate, boil for two hours on a wire gauze support, keeping the solution to the 500 cc. mark. The total extractive weigh. This contains "cutose," coloring matter, albuminoid matter, decomposition products, etc. VIII. The residue from VII. is washed first with water, then with alcohol, then with ether. Finally dried and weighed, then ignited, the difference being cellulose. The amount record. IX.-The nitrogen in the drug may be estimated by the Kjeldahl method (see Proc. of the sixth annual convention of the Association of Official Agricultural Chemists, 1889, p. 218). The amount of albumen corresponding to the amount of nitrogen may then be computed. (See also Dragendorff, p. 79.) SUMMARY. In reporting a summary of the analysis, the following may be a guide: Solubilities of Ash......... Inorganic Constituents. Volatile Oil, III. (a). Fixed Oil, III. (b) Resin, III. (c); IV. (a). Waxy (?) matter, III. (d).. Organic Acids and Allies, IV. (b)......................... Glucose, IV. (c)..................................... Extractive (containing alkaloid [?]), IV. (d)..... Colored Extractive and Albuminoids, V. (d). Inert Coloring Matter, VI. (a)................. Starch and Allied Substances, VI. (b) ..... ........ ASSAY PROCESSES. The student is advised to practically study the assay processes of the U. S. P., 1890, given under Opium, Cinchona and Ext. Nux Vomica. A brief synopsis of the latter may be stated as follows: A definite quantity of the dried extract is treated with a mixture of Alcohol and of Ammonia Water (sp. g. .960). The mixture agitated with different portions of chloroform in a separator and the chloroformic layers drawn off, mixed and evaporated. The chloroformic residue is dis solved in n H2SO; the solution titrated with KOH, using n 100 Brazil wood as indicator. From figures obtained in the titration, by simple calculation the percentage of total alkaloids can be obtained. (See U. S. P., 1890, p. 154.) THE INORGANIC COMPOUNDS. How may the elements be classified for pharmaceutical study? The inorganic elements and official compounds may be classified as follows: (Compounds to be classed under the metallic or basic elements.) The Inorganic bases. ALKALIES: Potassium; Sodium; Lithium; Ammonium. ALKALINE EARTHS: Barium; Calcium; Magnesium; Strontium. ARSENIC GROUP: Arsenic; Antimony; Bismuth. UNGROUPED: Zinc; Lead; Silver; Gold; Platinum; (Copper and Mercury); (Iron; Manganese and Chromium); Aluminum; Cerium. Non-metallic Elements. HALOGENS: Chlorin; Bromin; Iodin. UNGROUPED: Hydrogen; Nitrogen; Oxygen; Sulfur; Phosphorus; Carbon; Boron; Silicon. The Inorganic Acids. Hydrochloric; Hydrobromic; Nitric; Nitro-hydrochloric; Sulfuric; Sulfurous; Phosphoric; Boric; Arsenious; Chromic. What are the characteristics of the alkalies. The metals of this group are all soft, fusible and volatile; they decompose water, forming hydrates which are caustic. |