METRONIDAZOLE BENZOATE SOP
1.0 OBJECTIVE:
To
lay down a procedure of analytical report for the active raw material of the Metronidazole Benzoate from the
Pharmacopoeial specifications.
2.0 SCOPE:
This
SOP shall be applicable in Q.C laboratory.
3.0 RESPONSIBILITY:
3.1
Q.C Analysts.
4.0 ACCOUNTABILITY:
4.1
Q.C Manager.
5.0 PROCEDURE:
5.1 Characters:
5.1.1
Appearance:
5.1.1.1
White or slightly yellowish.
5.1.1.2
Crystalline powder
or flakes.
5.1.2
Solubility:
5.1.2.1
Material and equipment:
5.1.2.1.1
Glassware (4 test
tubes, 1 spatula, 1 pipette).
5.1.2.1.2
Acetone.
5.1.2.1.3
Alcohol.
5.1.2.1.4
Purified water.
5.1.2.1.5
Methylene
chloride.
5.1.2.2
Sample:
5.1.2.2.1
Small quantity.
5.1.2.3
Method:
5.1.2.3.1
Take 4 test tubes
and add small quantity of sample for testing solubility according to B.P
specifications.
5.1.2.3.2
Add purified water
in test tube 1 and observe.
5.1.2.3.3
Add Methylene
chloride in test tube 2 and observe.
5.1.2.3.4
Add acetone in
test tube 3 and observe.
5.1.2.3.5
Add alcohol in
test tube 4 and observe.
5.1.2.4
Observations:
5.1.2.4.1
The sample in test
tube 1 containing with purified water is practically insoluble.
5.1.2.4.2
The sample in test
tube 2 containing with methylene chloride is freely soluble.
5.1.2.4.3
The sample in test
tube 3 containing with acetone is soluble.
5.1.2.4.4
The sample in test
tube 4 containing with alcohol is slightly soluble.
5.2 Identification
tests:
5.2.1
Melting
point determination:
5.2.1.1
Material and equipment:
5.2.1.1.1
Glassware
(according to requirement).
5.2.1.1.2
Melting point
apparatus.
5.2.1.1.3
Capillary tubes.
5.2.1.1.4
Purified water.
5.2.1.2
Sample:
5.2.1.2.1
Sufficient
quantity of sample.
5.2.1.3
Method:
5.2.1.3.1
Introduce the sufficient
quantity of sample into a capillary tube.
5.2.1.3.2
Set the apparatus
and immerse the capillary tube into the apparatus such that the closed end is
near the centre of the bulb of thermometer.
5.2.1.3.3
Switch on the
melting point apparatus.
5.2.1.3.4
Operate the melting
point apparatus according to the SOP
5.2.1.3.5
Raise the
temperature of the apparatus.
5.2.1.3.6
Record the
temperature at which the last particle passes into the liquid phase.
5.2.1.3.7
Record
measurements in annexure-1.
5.2.1.4
Observations:
5.2.1.4.1
The melting point
is 99oC-102oC.
5.2.2
UV/VIS
absorption Spectrophotometry:
5.2.2.1
Material and equipm4ent:
5.2.2.1.1
UV/VIS
Spectrophotometer.
5.2.2.1.2
Glassware
(according to requirement).
5.2.2.1.3
103g/L solution of
hydrochloric acid R.
5.2.2.2
Sample:
5.2.2.2.1
0.100g.
5.2.2.3
Method:
5.2.2.3.1
Test
solution:
5.2.2.3.1.1 Take
a beaker of 100.0ml and add 0.100g of sample in it.
5.2.2.3.1.2 Add
in it 103g/L solution of hydrochloric acid R.
5.2.2.3.1.3 Dissolve
it by using magnetic stirrer i.e. SOP
5.2.2.3.1.4 And
dilute it to 100.0ml with the same acid.
5.2.2.3.1.5 Take
1.0ml of this solution in 100.0ml of beaker.
5.2.2.3.1.6 And
dilute it to 100.0ml with 103g/L solution of hydrochloric acid R.
5.2.2.3.2
Spectral
range:
5.2.2.3.2.1 220-350nm.
5.2.2.3.3
Absorption
maximum:
5.2.2.3.3.1 At
232nm and 275nm.
5.2.2.3.4
Operate the UV/VIS
spectrophotometer according to the SOP.
5.2.2.3.5
Measure the absorption
maximum at given spectral range.
5.2.2.3.6
Measure the
absorbance of the resulting solution at the maximum wavelength 232nm and 275nm.
5.2.2.3.7
Note down values
of absorbance in annexure-2.
5.2.2.3.8
Calculate the
specific absorbances at the absorption maximum by using formula:
1cmA1% = __a__
b.c
5.2.2.4
Observations:
5.2.2.4.1
Specific
absorbance at absorption maximum at 232nm:
5.2.2.4.1.1 525
to 575nm.
5.2.3
Primary
aromatic amines test:
5.2.3.1
Material and equipment:
5.2.3.1.1
Glassware (1 test
tube, 1 pipette, 1 spatula).
5.2.3.1.2
Water bath.
5.2.3.1.3
10.0mg of zinc
chloride.
5.2.3.1.4
1.0ml of purified
water.
5.2.3.1.5
0.3ml of
hydrochloric acid R.
5.2.3.1.6
0.2ml of sodium
nitrite solution R.
5.2.3.1.7
1.0ml of
β-naphthol solution R.
5.2.3.2
Sample:
5.2.3.2.1
10.0mg.
5.2.3.3
Method:
5.2.3.3.1
Take a test tube
add in it 10.0mg of sample, 10.0mg of zinc chloride R, 1.0ml of purified water
R and 0.3ml of hydrochloric acid R. Dissolve it.
5.2.3.3.2
Heat it on water
bath for 5 minutes. And after that cool it.
5.2.3.3.3
Acidify the
solution with dilute hydrochloric acid R and add 0.2ml of sodium nitrite
solution R.
5.2.3.3.4
After 1 minute to
2 minute, add 1.0ml of β-naphthol solution R.
5.2.3.3.5
Observe the
changes.
5.2.3.4
Observations:
5.2.3.4.1
An intense orange
or red colour and usually a ppt of the same colour are produced.
5.3 Loss
on drying:
5.3.1
Material and equipment:
5.3.1.1
Glassware
(according to requirement).
5.3.1.2
Analytical weighing
balance.
5.3.1.3
Oven.
5.3.2
Sample:
5.3.2.1
1.0g.
5.3.3
Method:
5.3.3.1
Weigh 1.0g of the
test sample.
5.3.3.2
Set the oven
apparatus. Operate it according to the SOP.
5.3.3.3
Place the sample
into the tray and dry it.
5.3.3.4
Set the
temperature of oven at 80oC for at least 3hours.
5.3.3.5
And wait till the
sample loses its moisture.
5.3.3.6
After 3hours weigh
the sample again by using analytical weighing balance i.e. the final weight.
5.3.3.7
Note down readings
on given Annexure-3.
5.3.4
Observation:
5.3.4.1
Maximum 0.5%.
5.4 Assay:
5.4.1
Apparatus:
5.4.1.1
Glassware
(according to requirement).
5.4.1.2
Potentiometer.
5.4.1.3
Magnetic stirrer.
5.4.2
Material
and reagents:
5.4.2.1
50.0ml of anhydrous
acetic acid R.
5.4.2.2
0.1M Perchloric
acid.
5.4.2.3
Crystal violet
solution (as an indicator).
5.4.3
Sample:
5.4.3.1
0.250g.
5.4.4
Method
of analysis:
5.4.4.1 Take
a 50.0ml of beaker and add 0.250g of sample in it.
5.4.4.2 Add
50.0ml of anhydrous acetic acid R in it and dissolve by using magnetic stirrer
i.e. SOP.
5.4.4.3 Fill
the right hand side burette with titrant 0.1M Perchloric acid.
5.4.4.4 Carry
out a Potentiometric titration using crystal violet solution as an indicator.
5.4.4.5 Operate
potentiometer according to SOP.
5.4.4.6 To
neutralize analyte add titrant fixed volume (1ml, 0.5ml or 0.1ml) from burette
every time note the reading of change in potential difference (millivolts) for
each addition in given annexure-4.
5.4.4.7 Plot
a graph, volume used v/s millivolts.
5.4.4.8 Find
out the END POINT.
5.4.4.9 Peak
of graph indicates END POINT i.e. the point at which maximum millivolts. Note
down volume used at that point.
5.4.4.10 Perform
blank titration without using sample. Similarly, as sample titration performed. Record observations in annexure-4.
5.4.4.11 Calculate
volume used by substance by using formula:
Volume used by
substance = Blank titration - Sample titration.
5.4.4.12 Calculate
percentage purity of the sample by using formula:
%age purity = volume
used by substance x factor x 100
Weight of sample
5.4.5
Factor:
5.4.5.1 1ml
of 0.1M Perchloric acid is equivalent to 27.53mg of Metronidazole benzoate C13H13N3O4.
5.4.6
Limit:
5.4.6.1
98.5% to 101.0% (dried
substance).
6.0 REVISION LOG:
|
Revision No.
|
Effective Date
|
Reason
|
|
00
|
|
New SOP
|
7.0 REFERENCES:
7.1
The British
Pharmacopoeia. Vol II.,
Official Monograph / Metronidazole: 2015, pp. 281-282.
8.0 ANNEXURES:
Annexure 1: Observations
of Melting point apparatus.
Annexure 2: Observations
of UV/VIS spectrophotometer.
Annexure 3: Observations
of Percentage Loss of drying by using oven.
Annexure 4: Assay
observations and calculations (Potentiometric titration).
Annexure: 1
Observations
of Melting point apparatus
Sample
= _____________
Time
period = _____________
|
Sr.#
|
Initial (Ti)
(oC)
|
Final (Tf)
(oC)
|
Tf - Ti
(oC)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Average:
_____________
Result: _________________
Remarks:
_______________________________________________________________
Annexure: 2
Observations
and Calculations of UV/VIS spectrophotometer
|
UV/VIS spectrophotometer
Model:
_____________________________ Date: _________________
OBSERVATIONS:
CALCULATIONS:
1cmA1%
= __a__
b.c
Results:
_______________
Remarks:
______________________________________________________________
|
Annexure:
3
Observations
of percentage loss of drying by using Oven
|
Percentage
loss of drying by using Oven
Apparatus:
____________________
Temperature:
__________________
Weight
of Sample = _____________
Time
period = _____________
Pressure=
_________________
Average % Loss of Moisture: _____________
Remarks:
_______________________________________________________________
|
||||||||||||||||||||||||
Annexure: 4
Assay
observations and calculations (Potentiometric titration)
|
Potentiometric titration
Reference
electrode: ___________________
Indicator
electrode: ____________________
Speed
of magnetic stirrer: _______________
Titrant
used: __________________________
Indicator:
____________________________
Blank
titration:
Plot a graph, volume used v/s millivolts and find out peak
of graph i.e. END POINT of blank titration.
Sample
titration:
Plot a graph, volume used v/s millivolts and find out peak
of graph i.e. END POINT of sample titration:
Volume used by Blank titration: __________________
Volume used by Sample titration: _________________
Volume used by substance = Blank titration - Sample
titration.
mV used by Blank titration: __________________
mV used by Sample titration: _________________
mV used by substance = Blank
titration - Sample titration.
Volume
used by substance: _______________________
Voltmeter
(mV) used by substance: _________________
RESULT: ____________________________________________________________
|
9.0 ABBREVIATIONS:
|
Abbreviation
|
Expanded Form
|
|
SOP
|
Standard
operating procedure
|
|
&
|
And
|
|
No.
|
Number
|
|
Ltd.
|
Limited
|
|
Q.C
|
Quality
control
|
|
%
|
Percentage
|
|
B.P
|
British
pharmacopoeia
|
|
mg
|
Milligram
|
|
ml
|
Milliliter
|
|
g
|
Grams
|
|
M
|
Molar
|
|
Vol
|
Volume
|
|
QCA
|
Quality
control active ingredient
|
|
F
|
Format
|
|
v/s
|
Verses
|
|
Mv
|
Millivolts
|
|
oC
|
Degree
centigrade
|
|
R
|
Reagent
|
|
Ti
|
Initial
temperature
|
|
Tf
|
Final
temperature
|
|
Temp.
|
Temperature
|
|
λ
|
Lambda
|
|
UV/VIS
|
Ultraviolet/
visible
|
|
nm
|
Nanometer
|
|
h
|
Hours
|
|
A
|
Absorbance
|