SODIUM CYCLAMATE Natrii cyclamas

EUROPEAN PHARMACOPOEIA 5.0 Sodium dihydrogen phosphate dihydrate
Sulphamic acid. Examine by thin-layer chromatography
(2.2.27), using a TLC silica gel G plate R.
Test solution (a). Use solution S.
Test solution (b). Dilute 1 ml of test solution (a) to 10 ml
with water R.
Reference solution (a). Dissolve 0.10 g of sodium
cyclamate CRS in water R and dilute to 10 ml with the same
solvent.
Reference solution (b). Dissolve10mgofsulphamic acid R
in water R anddiluteto100mlwiththesamesolvent.
Apply to the plate 2 µl of each solution. Develop over a path
of 12 cm using a mixture of 10 volumes of concentrated
ammonia R, 10 volumes of water R, 20 volumes of ethyl
acetate R and 70 volumes of propanol R. Drytheplateina
currentofwarmair,heatat105°Cfor5minandspraythe
hot plate with strong sodium hypochlorite solution R diluted
to a concentration of 5 g/l of active chlorine. Place the plate
in a current of cold air until an area of coating below the
points of application gives at most a faint blue colour with
adropofpotassium iodide and starch solution R; avoid
prolonged exposure to cold air. Spray with potassium iodide
and starch solution R and examine the chromatograms
within 5 min. Any spot corresponding to sulphamic acid
in the chromatogram obtained with test solution (a) is not
more intense than the spot in the chromatogram obtained
with reference solution (b) (0.1 per cent).
Aniline, cyclohexylamine and dicyclohexylamine. Not
more than 1 ppm of aniline, not more than 10 ppm
of cyclohexylamine and not more than 1 ppm of
dicyclohexylamine determined by gas chromatography
(2.2.28) usingtetradecane R as the internal standard.
Internal standard solution. Dissolve 2 µl of tetradecane R
in methylene chloride R anddiluteto100mlwiththesame
solvent.
Test solution. Dissolve 2.00 g of the substance to be
examined in 20 ml of water R and add 0.5 ml of strong
sodium hydroxide solution R and shake with 30 ml of
toluene R. Shake 20 ml of the upper layer with 4 ml of a
mixture of equal volumes of dilute acetic acid R and water R.
Separate the lower layer and add 0.5 ml of strong sodium
hydroxide solution R and 0.5 ml of the internal standard
solution. Shake and use the lower layer for chromatography
immediately after separation.
Reference solution. Dissolve10.0mg(about12µl)
of cyclohexylamine R, 1.0mg(about1.1µl)of
dicyclohexylamine R and 1.0 mg (about 1 µl) of aniline R
in water R and dilute to 1000 ml with the same solvent.
Dilute 10.0 ml of this solution to 100.0 ml with water R
(solution A). To 20.0 ml of solution A, add 0.5 ml of strong
sodium hydroxide solution R and extract with 30 ml of
toluene R. Shake 20 ml of the upper layer with 4 ml of a
mixture of equal volumes of dilute acetic acid R and water R.
Separate the lower layer and add 0.5 ml of strong sodium
hydroxide solution R and 0.5 ml of the internal standard
solution. Shake and use the lower layer for chromatography
immediately after separation.
The chromatographic procedure may be carried out using:
— a fused silica column 25 m long and 0.32 mm in internal
diameter coated with poly(dimethyl)(diphenyl)siloxane R
(0.51 µm),
— helium for chromatography R as the carrier gas at a flow
rate of 1.8 ml/min,
— a flame-ionisation detector,
— asplitventataflowrateof20ml/min,
withthefollowingtemperatureprogramme:
Time
(min)
Temperature
(°C)
Rate
(°C/min)
Comment
Column 0-1 85 isothermal
1-9 85→150 8 linear gradient
9-13 150 isothermal
Injection port 250
Detector 270
Inject 1.5 µl of each solution. When the chromatograms are
recorded in the conditions prescribed, the retention times
relative to cyclohexylamine (about 2.3 min) are the
following: aniline about 1.4, tetradecane about 4.3 and
dicyclohexylamine about 4.5.
Sulphates (2.4.13). Dilute 1.5 ml of solution S to 15 ml with
distilled water R. The solution complies with the limit test
for sulphates (0.1 per cent).
Heavy metals (2.4.8). 12 ml of solution S complies with limit
test A for heavy metals (10 ppm). Prepare the standard using
lead standard solution (1 ppm Pb) R.
Loss on drying (2.2.32). Not more than 1.0 per cent,
determined on 1.000 g in an oven at 100 °C to 105 °C for 4 h.
ASSAY
Dissolve without heating 0.150 g in 60 ml of anhydrous
acetic acid R.Titratewith0.1Mperchloric acid,determining
the end-point potentiometrically (2.2.20).
1mlof0.1 M perchloric acid is equivalent to 20.12 mg of
C6H12NNaO3S. IMPURITIES
A. sulphamic acid,
B. aniline (phenylamine),
C. cyclohexanamine,
D. N-cyclohexylcyclohexanamine.
01/2005:0194
SODIUM DIHYDROGEN PHOSPHATE
DIHYDRATE
Natrii dihydrogenophosphas dihydricus
NaH2PO4,2H2O Mr 156.0
DEFINITION
Sodium dihydrogen phosphate dihydrate contains not less
than 98.0 per cent and not more than the equivalent of
100.5 per cent of NaH2PO4, calculated with reference to the
dried substance.
GeneralNotices(1)applytoallmonographsandothertexts 2431