Amobarbital sodium.pdf

EUROPEAN PHARMACOPOEIA 5.0
Amobarbital sodium
D. It gives the reaction of non-nitrogen substituted
barbiturates (2.3.1).
TESTS
Appearance of solution. Dissolve1.0ginamixtureof4ml
of dilute sodium hydroxide solution R and 6 ml of water R.
The solution is clear (2.2.1) and not more intensely coloured
than reference solution Y 6
(2.2.2, Method II).
Acidity or alkalinity. To1.0gadd50mlofwater R and boil
for 2 min. Allow to cool and filter. To 10 ml of the filtrate
add 0.15 ml of methyl red solution R and 0.1 ml of 0.01 M
sodium hydroxide. The solution is yellow. Add 0.2 ml of
0.01 M hydrochloric acid. Thesolutionisred.
Related substances. Examine by thin-layer chromatography
(2.2.27), using silica gel GF 254
R as the coating substance.
Test solution.Dissolve1.0gofthesubstancetobeexamined
in alcohol R and dilute to 100 ml with the same solvent.
Reference solution. Dilute 0.5 ml of the test solution to
100 ml with alcohol R.
Apply separately to the plate 20 µl of each solution. Develop
over a path of 15 cm using the lower layer from a mixture
of 5 volumes of concentrated ammonia R, 15 volumes of
alcohol R and 80 volumes of chloroform R. Examinethe
plate immediately in ultraviolet light at 254 nm. Any spot
in the chromatogram obtained with the test solution, apart
from the principal spot, is not more intense than the spot
in the chromatogram obtained with the reference solution.
Spray with diphenylcarbazone mercuric reagent R. Allow
the plate to dry in air and spray with freshly prepared
alcoholic potassium hydroxide solution R diluted 1 in 5 with
aldehyde-free alcohol R. Heatat100°Cto105°Cfor5min
and examine immediately. Any spot in the chromatogram
obtained with the test solution, apart from the principal
spot, is not more intense than the spot in the chromatogram
obtained with the reference solution (0.5 per cent).
Loss on drying (2.2.32). Not more than 0.5 per cent,
determined on 1.000 g by drying in an oven at 100 °C to
105 °C.
Sulphated ash (2.4.14). Not more than 0.1 per cent,
determined on 1.0 g.
ASSAY
Dissolve 0.100 g in 5 ml of pyridine R. Add 0.5 ml of
thymolphthalein solution R and 10 ml of silver nitrate
solution in pyridine R. Titratewith0.1 M ethanolic sodium
hydroxide until a pure blue colour is obtained. Carry out
a blank titration.
1mlof0.1 M ethanolic sodium hydroxide is equivalent to
11.31 mg of C 11
H 18
N 2
O 3
.
AMOBARBITAL SODIUM
Amobarbitalum natricum
01/2005:0166
C 11
H 17
N 2
NaO 3
M r
248.3
DEFINITION
Amobarbital sodium contains not less than 98.5 per cent and
not more than the equivalent of 102.0 per cent of sodium
derivative of 5-ethyl-5-(3-methylbutyl)pyrimidin-2,4,6(1H,3H,
5H)-trione, calculated with reference to the dried substance.
CHARACTERS
A white, granular powder, hygroscopic, very soluble in
carbon dioxide-free water (a small fraction may be insoluble),
freely soluble in alcohol.
IDENTIFICATION
First identification: A, B, E.
Secondidentification:A,C,D,E.
A. Acidify 10 ml of solution S (see Tests) with dilute
hydrochloric acid R and shake with 20 ml of ether R.
Separate the ether layer, wash with 10 ml of water R, dry
over anhydrous sodium sulphate R and filter. Evaporate
thefiltratetodrynessanddrytheresidueat100°C
to 105 °C (test residue). Repeat the operations using
0.1 g of amobarbital sodium CRS (reference residue).
Determine the melting point (2.2.14) of the test residue.
Mix equal parts of the test residue and the reference
residueanddeterminethemeltingpointofthemixture.
The difference between the melting points (which are
about 157 °C) is not greater than 2 °C.
B. Examine by infrared absorption spectrophotometry
(2.2.24), comparing the spectrum obtained with the
reference residue prepared from amobarbital sodium CRS
with that obtained with the test residue (see identification
test A).
C. Examine by thin-layer chromatography (2.2.27), using
silica gel GF 254
R as the coating substance.
Test solution. Dissolve 0.1 g of the substance to be
examined in alcohol R anddiluteto100mlwiththesame
solvent.
Reference solution. Dissolve 0.1 g of amobarbital
sodium CRS in alcohol R and dilute to 100 ml with the
same solvent.
Apply separately to the plate 10 µl of each solution.
Develop over a path of 18 cm using the lower layer of
a mixture of 5 volumes of concentrated ammonia R,
15 volumes of alcohol R and 80 volumes of chloroform R.
Examine immediately in ultraviolet light at 254 nm. The
principal spot in the chromatogram obtained with the test
solution is similar in position and size to the principal
spot in the chromatogram obtained with the reference
solution.
D. It gives the reaction of non-nitrogen substituted
barbiturates (2.3.1).
E. It gives reaction (a) of sodium (2.3.1).
TESTS
Solution S. Dissolve5.0ginalcohol (50 per cent V/V) R
and dilute to 50 ml with the same solvent.
Appearance of solution. Solution S is clear (2.2.1) andnot
more intensely coloured than reference solution Y 7
(2.2.2,
Method II).
pH (2.2.3). Dissolve 5.0 g in carbon dioxide-free water R
and dilute to 50 ml with the same solvent. Disregard any
slight residue. The pH of the solution is not more than 11.0.
Related substances. Examine by thin-layer chromatography
(2.2.27), using silica gel GF 254
R as the coating substance.
Test solution.Dissolve1.0gofthesubstancetobeexamined
in alcohol R and dilute to 100 ml with the same solvent.
GeneralNotices(1)applytoallmonographsandothertexts 989

Amoxicillin sodium EUROPEAN PHARMACOPOEIA 5.0
Reference solution. Dilute 0.5 ml of the test solution to
100 ml with alcohol R.
Apply separately to the plate 20 µl of each solution. Develop
over a path of 15 cm using the lower layer of a mixture
of 5 volumes of concentrated ammonia R, 15volumes
of alcohol R and 80 volumes of chloroform R. Examine
the plate immediately in ultravioletlightat254nm.Spray
with diphenylcarbazone mercuric reagent R. Allowthe
plate to dry in air and spray with freshly prepared alcoholic
potassium hydroxide solution R diluted 1 in 5 with
aldehyde-free alcohol R. Heatat100°Cto105°Cfor5min
and examine immediately. When examined in ultraviolet
light and after spraying, any spot in the chromatogram
obtained with the test solution, apart from the principal
spot, is not more intense than the spot in the chromatogram
obtained with the reference solution (0.5 per cent). Disregard
any spot at the starting-point.
Loss on drying (2.2.32). Not more than 3.0 per cent,
determinedon0.50gbydryinginanovenat130°C.
ASSAY
Dissolve 0.200 g in 5 ml of ethanol R. Add0.5mlof
thymolphthalein solution R and 10 ml of silver nitrate
solution in pyridine R. Titratewith0.1 M ethanolic sodium
hydroxide until a pure blue colour is obtained. Carry out
a blank titration.
1mlof0.1 M ethanolic sodium hydroxide is equivalent to
24.83 mg of C 11
H 17
N 2
NaO 3
.
STORAGE
Storeinanairtightcontainer.
AMOXICILLIN SODIUM
Amoxicillinum natricum
01/2005:0577
corrected
C 16
H 18
N 3
NaO 5
S M r
387.4
DEFINITION
Amoxicillin sodium contains not less than 89.0 per
cent and not more than the equivalent of 102.0 per
cent of sodium (2S,5R,6R)-6-[[(2R)-2-amino-2-(4-
hydroxyphenyl)acetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-
azabicyclo[3.2.0]heptane-2-carboxylate, calculated with
reference to the anhydrous substance.
CHARACTERS
A white or almost white powder, very hygroscopic, very
soluble in water, sparingly soluble in ethanol, very slightly
soluble in acetone.
IDENTIFICATION
First identification: A, D.
Second identification: B, C, D.
A. Dissolve 0.250 g in 5 ml of water R, add0.5mlofdilute
acetic acid R, swirlandallowtostandfor10mininiced
water. Filter the crystals and wash with 2 ml to 3 ml
of a mixture of 1 volume of water R and 9 volumes of
acetone R, then dry in an oven at 60 °C for 30 min.
Examine by infrared absorption spectrophotometry
(2.2.24), comparing with the spectrum obtained with
amoxicillin trihydrate CRS.
B.Examinebythin-layerchromatography(2.2.27), using a
TLC silanised silica gel plate R.
Test solution. Dissolve25mgofthesubstancetobe
examined in 10 ml of sodium hydrogen carbonate
solution R.
Reference solution (a). Dissolve25mgofamoxicillin
trihydrate CRS in 10 ml of sodium hydrogen carbonate
solution R.
Reference solution (b). Dissolve25mgofamoxicillin
trihydrate CRS and 25 mg of ampicillin trihydrate CRS
in 10 ml of sodium hydrogen carbonate solution R.
Apply to the plate 1 µl of each solution. Develop over a
path of 15 cm using a mixture of 10 volumes of acetone R
and 90 volumes of a 154 g/l solution of ammonium
acetate R, the pH of which has been adjusted to 5.0 with
glacial acetic acid R. Allow the plate to dry in air and
expose it to iodine vapour until the spots appear. Examine
in daylight. The principal spot in the chromatogram
obtained with the test solution is similar in position,
colour and size to the principal spot in the chromatogram
obtained with reference solution (a). The test is not
valid unless the chromatogram obtained with reference
solution (b) shows 2 clearly separated spots.
C. Place about 2 mg in a test-tube about 150 mm long and
15 mm in diameter. Moisten with 0.05 ml of water R and
add 2 ml of sulphuric acid-formaldehyde reagent R.
Mix the contents of the tube by swirling; the solution is
practically colourless. Place the test-tube in a water-bath
for 1 min; a dark yellow colour develops.
D. It gives reaction (a) of sodium (2.3.1).
TESTS
Appearance of solution. Dissolve1.0ginwater R and
dilute to 10.0 ml with the same solvent. Immediately after
dissolution, the solution is not more opalescent than
reference suspension II (2.2.1). The solution may show an
initial, but transient, pink colour. After 5 min, the absorbance
measured at 430 nm (2.2.25) is not greater than 0.20.
pH (2.2.3). Dissolve 2.0 g in carbon dioxide-free water R
and dilute to 20 ml with the same solvent. The pH of the
solution is 8.0 to 10.0.
Specific optical rotation (2.2.7).Dissolve62.5mgina4g/l
solution of potassium hydrogen phthalate R and dilute to
25.0 ml with the same solution. The specific optical rotation
is+240to+290,calculatedwithreferencetotheanhydrous
substance.
Related substances. Examinebyliquidchromatography
(2.2.29) as described under Assay. Inject 50 µl of reference
solution (d) and elute isocratically until elution of the
amoxicillin peak. Inject 50 µl of test solution (b) and start
the elution isocratically. Immediately after elution of the
amoxicillin peak start the following linear gradient. If the
mobile phase composition has been adjusted to achieve the
required resolution, the adjusted composition will apply at
time zero in the gradient.
Time
(min)
Mobile phase A
(per cent V/V)
Mobile phase B
(per cent V/V)
Comment
0-25 92 → 0 8 → 100 linear gradient
25 - 40 0 100 isocratic
40 - 55 92 8 re-equilibration
990 See the information section on general monographs (cover pages)