See phases for gas chromatography in the Chromatographic Reagents
section under Chromatography 621.
Gadolinium (Gd III) Acetate Hydrate,
White, crystalline, hygroscopic powder. Irritant. Use a suitable grade.
White crystals or crystalline powder. Stable in air. One g dissolves in 30 mL of water to yield a clear, colorless solution. Store in cool to room temperature in a dry area.
White, crystalline powder. Practically insoluble in water, in chloroform, and in ether; slightly soluble in pyridine and in diluted alcohol. Melts at about 250
, with decomposition.
Specific rotation 781:
, determined in a solution of pyridine containing 10 mg per mL, with the use of a mercury light at 546.1 nm; between +21
, determined in a solution of equal parts of chloroform and methanol containing 5 mg per mL, with the use of sodium light.
Dissolve 10 mg each of USP Digitoxin RS
, previously dried, USP Digoxin RS
, previously dried, and gitoxin, respectively, in separate 5-mL portions of a mixture of 2 parts of chloroform and 1 part of methanol, and dilute each with additional solvent mixture to 10 mL. Then proceed as directed in the Identification test
. The chromatogram of gitoxin shows one fluorescent spot, located between the digoxin and digitoxin spots.
Fine threads of glass.
Boil 1 g for 30 minutes with 30 mL of diluted hydrochloric acid, and filter. Evaporate the filtrate, and dry the residue at 105
to constant weight: the residue weighs not more than 5 mg (0.5%).
Boil 2 g with a mixture of 25 mL each of diluted nitric acid and water for 5 minutes, and filter. Evaporate one-half of the filtrate to dryness, dissolve the residue in 10 mL of water to which 3 drops of hydrochloric acid have been added, filter if necessary, and add an equal volume of hydrogen sulfide TS
to the filtrate: no darkening is produced.
D-Gluconic Acid, 50 Percent in Water,
Pale yellow liquid.
Dilute about 200 mg of the solution, accurately weighed, with 30 mL of water. Titrate with 0.1 N sodium hydroxide VS, determining the endpoint potentiometrically. Perform a blank determination and make any necessary correction. Each mL of 0.1 N sodium hydroxide is equivalent to 19.62 mg of C6H12O7. Not less than 49.0% is found.
Use a suitable grade. A white, crystalline powder, with a sweet taste. Freely soluble in water; sparingly soluble in alcohol.
Use a suitable grade.
]Use a suitable grade.
]White powder or white powder with a faint yellow cast. Use a suitable grade.
]White, crystalline powder. Use a suitable grade.
Use ACS reagent grade Glycerol.
White crystalline powder or chunks.
Inject an appropriate volume (silanized) into a gas chromatograph (see Chromatography 621
) equipped with a flame-ionization detector, helium being used as the carrier gas. The following conditions have been found suitable: a 0.25-mm × 30-m capillary column coated with a 1-µm layer of phase G2. The injection port temperature is maintained at 250
; the detector temperature is maintained at 300
; the column temperature is maintained at 100
and programmed to rise 10
per minute to 250
. The area of the C2
peak is not less than 98.5% of the total peak area.
Use ACS reagent grade.
Change to read:
Colorless to yellowish, refractive liquid. USP29
Soluble in about 65 parts of water; soluble in sodium hydroxide solution; miscible with alcohol, with chloroform, with ether, and with glacial acetic acid.
When examined by gasliquid chromatography, it shows a purity of not less than 98%. The following conditions have been found suitable for assaying it: a 3-mm × 1.8-m stainless steel column containing liquid phase G16 on 60- to 80-mesh support S1A. Helium is the carrier gas, the injection port temperature is maintained at 180
, the column temperature is maintained at 200
, and the flame-ionization detector is maintained at 280
. The retention time is about 8 minutes.
White crystalline powder. Freely soluble in water and in alcohol.
Dissolve about 400 mg, accurately weighed, in 5 mL of water. Add 5 mL of glacial acetic acid, 50 mL of methanol, and 1 drop of eosin Y TS
, and titrate with 0.1 N silver nitrate VS. Each mL of 0.1 N silver nitrate is equivalent to 3.545 mg of Cl. Not less than 36.1% and not more than 37.1%, calculated on the anhydrous basis, is found.
]White powder or colorless crystals. Use a suitable grade.
White, crystalline powder. Melts above 250
, with decomposition. Slightly soluble in water and in alcohol; soluble in acidulated water and in sodium hydroxide TS
. Its solutions are not precipitated by iodine TS or by mercuric-potassium iodide TS, but form a precipitate with trinitrophenol TS.
Residue on ignition (Reagent test):
negligible, from 100 mg.
Loss on drying 731
Dry it at 105
to constant weight: it loses not more than 10.0% of its weight.