» Adenine contains not less than 98.0 percent and not more than 102.0 percent of C5H5N5, calculated on the dried basis.
Packaging and storage Preserve in well-closed containers.
Identification, Infrared Absorption 197K.
Loss on drying 731 Dry it at 110 for 4 hours: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.1%.
Heavy metals, Method II 231: 0.001%.
pH 7.0 Phosphate buffer Dissolve 4.54 g of monobasic potassium phosphate in water to make 500 mL of solution. Dissolve 4.73 g of anhydrous dibasic sodium phosphate in water to make 500 mL of solution. Mix 38.9 mL of the monobasic potassium phosphate solution with 61.1 mL of the dibasic sodium phosphate solution. Adjust, if necessary, by the dropwise addition of the dibasic sodium phosphate solution to a pH of 7.0.
Standard preparations Dissolve a suitable quantity of USP Adenine RS, accurately weighed, in hot water, cool, and dilute quantitatively with water to obtain a solution having a known concentration of about 0.19 mg per mL. Pipet 5-mL portions into three 100-mL volumetric flasks, dilute with 0.10 N hydrochloric acid, 0.010 N sodium hydroxide, and pH 7.0 Phosphate buffer, respectively, to volume, and mix.
Test preparations Proceed as directed for Standard preparations, using the specimen in place of the Reference Standard.
Procedure Obtain the UV absorption spectra of the Test preparations and the Standard preparations concomitantly, in 1-cm cells, covering the range between 220 nm and 320 nm, using water as the blank. The respective absorptivities, calculated on the dried basis, at the wavelengths of maximum absorbance, for each pair of corresponding solutions do not differ by more than 2.0%.
Nitrogen content, Method II 461 Not less than 50.2% and not more than 53.4% is found, calculated on the dried basis.
0.1 N Perchloric acid Standardize 0.1 N perchloric acid VS as follows. Transfer about 300 mg of potassium biphthalate, accurately weighed, to a 150-mL beaker, and dissolve in 80 mL of a mixture of 100 mL of glacial acetic acid and 300 mL of acetic anhydride, by stirring. Titrate with the perchloric acid solution, determining the endpoint potentiometrically. Each 20.42 mg of potassium biphthalate is equivalent to 1 mL of 0.1 N perchloric acid.
Procedure Transfer about 200 mg of Adenine, accurately weighed, to a 150-mL beaker, and dissolve in 80 mL of a mixture of 100 mL of glacial acetic acid and 300 mL of acetic anhydride, by stirring. Titrate with 0.1 N Perchloric acid, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N Perchloric acid is equivalent to 13.514 mg of C5H5N5.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 1432Pharmacopeial Forum: Volume No. 27(3) Page 2504
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.