THEOPHYLLINE METHOD OF ANALYSIS SOP
1.0 OBJECTIVE:
To
lay down a procedure for the active raw material of the Theophylline from the
Pharmacopoeial specifications.
2.0 SCOPE:
This
SOP shall be applicable in Q.C laboratory.
3.0 RESPONSIBILITY:
3.1
Q.C Analyst.
4.0 ACCOUNTABILITY:
4.1
Q.C Manager.
5.0 PROCEDURE:
5.1 Characters:
5.1.1
Appearance:
5.1.1.1
White or almost
white.
5.1.1.2
Crystalline
powder.
5.1.2
Solubility:
5.1.2.1
Material and equipment:
5.1.2.1.1
Glassware (5 test
tubes, 1 spatula, 1 pipette).
5.1.2.1.2
Ethanol (96%).
5.1.2.1.3
Mineral acids
(e.g. dilute HCl, dilute H2SO4, HNO3).
5.1.2.1.4
Solutions of
alkali hydroxide (e.g. NaOH, KOH).
5.1.2.1.5
Ammonia.
5.1.2.1.6
Purified water.
5.1.2.2
Sample:
5.1.2.2.1
Small quantity.
5.1.2.3
Method:
5.1.2.3.1
Take 5 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 ethanol (96%)
in test tube 2 and observe.
5.1.2.3.4
Add solution of
alkali hydroxide in test tube 3 and observe.
5.1.2.3.5
Add ammonia in
test tube 4 and observe.
5.1.2.3.6
Add dilute mineral
acid in test tube 5 and observe.
5.1.2.4
Observations:
5.1.2.4.1
The sample in test
tube 1 containing with purified water is slightly soluble.
5.1.2.4.2
The sample in test
tube 2 containing with ethanol (96%) is sparingly soluble.
5.1.2.4.3
The sample in test
tube 3, 4 & 5 containing with solution of alkali hydroxide, ammonia &
dilute mineral acid is dissolved.
5.2 Identification
tests:
5.2.1
Determination
of melting point:
5.2.1.1
Material and equipment:
5.2.1.1.1
Glassware (test
tubes, spatula).
5.2.1.1.2
Melting point
apparatus.
5.2.1.1.3
Capillary tubes.
5.2.1.2
Sample:
5.2.1.2.1
Sufficient
quantity of sample.
5.2.1.3
Method:
5.2.1.3.1
Take sample dry it
first in oven at 100-105oC, operate the oven according to SOP
5.2.1.3.2
Introduce the
sufficient quantity of sample into a capillary tube.
5.2.1.3.3
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.
5.2.1.3.4
Switch on the
melting point apparatus.
5.2.1.3.5
Operate the
melting point apparatus according to the SOP.
5.2.1.3.6
Raise the
temperature of the apparatus.
5.2.1.3.7
Record the
temperature at which the last particle passes into the liquid phase.
5.2.1.3.8
Record
measurements in annexure-1.
5.2.1.4
Observations:
5.2.1.4.1
The melting point
of theophylline is about 270oC to 274oC.
5.2.2
5.2.2.1
Material and equipment:
5.2.2.1.1
Glassware (1 test
tube, 1 pipette).
5.2.2.1.2
Water-bath.
5.2.2.1.3
1.0ml of 360g/L
solution of potassium hydroxide.
5.2.2.1.4
1.0ml of
diazotized sulfanilic acid solution.
5.2.2.2
Sample:
5.2.2.2.1
10.0mg.
5.2.2.3
Method:
5.2.2.3.1
Take a test tube
and add 10.0mg of sample in it and also add 1.0ml of 360g/L solution of
potassium hydroxide with the help of pipette.
5.2.2.3.2
Heat it in water
bath at 90oC for 3min.
5.2.2.3.3
Then add 1.0ml of
diazotized sulfanilic acid solution
5.2.2.3.4
Observe the
changes.
5.2.2.3.5
Carry out the
blank test too and observe its changes too.
5.2.2.4
Observations:
5.2.2.4.1
A red colour
slowly develops.
5.2.3
Loss
on drying:
5.2.3.1
Material and equipment:
5.2.3.1.1
Glassware
(according to requirement).
5.2.3.1.2
Analytical
weighing balance.
5.2.3.1.3
Oven.
5.2.3.2
Sample:
5.2.3.2.1
1.0g.
5.2.3.3
Method:
5.2.3.3.1
Weigh 1.0g of the
test sample.
5.2.3.3.2
Set the oven
apparatus. Operate it according to the SOP.
5.2.3.3.3
Place the sample
into the tray and dry it.
5.2.3.3.4
Set the
temperature of oven at 105oC for at least 45min.
5.2.3.3.5
And wait till the
sample loses its moisture.
5.2.3.3.6
After 45min weigh
the sample again by using analytical weighing balance i.e. the final weight.
5.2.3.3.7
Note down readings
on given Annexure-2.
5.2.3.4
Observation:
5.2.3.4.1
Maximum 0.5%.
5.2.4
Xanthine
test:
5.2.4.1
Material and equipment:
5.2.4.1.1
Glassware (1 test
tube, 1 pipette).
5.2.4.1.2
0.1ml of strong
hydrogen peroxide solution.
5.2.4.1.3
0.3ml of dilute
hydrochloric acid.
5.2.4.1.4
0.1ml of dilute
ammonia R2.
5.2.4.1.5
Water-bath.
5.2.4.2
Sample:
5.2.4.2.1
A few milligrams
of ppt obtained from point 5.2.1.
5.2.4.3
Method:
5.2.4.3.1
Take a test tube
and add few milligrams of ppt in it.
5.2.4.3.2
Add 0.1ml of
strong hydrogen peroxide solution and 0.3ml of dilute hydrochloric acid.
5.2.4.3.3
Heat it on
water-bath until it completely dry and yellowish-red residue is obtained.
5.2.4.3.4
Add 0.1ml of
dilute ammonia R2.
5.2.4.3.5
Observe the
changes.
5.2.4.4
Observations:
5.2.4.4.1
The colour of the
residue changes to violet-red.
5.3 Assay:
5.3.1
Apparatus:
5.3.1.1
Glassware (according
to requirement).
5.3.1.2
Titration
apparatus.
5.3.1.3
Magnetic stirrer.
5.3.2
Material
and reagents:
5.3.2.1
20.0ml of 0.1M
silver nitrate.
5.3.2.2
1.0ml of
bromothymol blue solution R1 (as indicator).
5.3.2.3
0.1M sodium
hydroxide.
5.3.2.4
Purified water.
5.3.3
Sample:
5.3.3.1
0.150g.
5.3.4
Method
of analysis:
5.3.4.1 Sample
titration:
5.3.4.1.1
Take a flask and
add in it 0.150g of sample.
5.3.4.1.2
Dissolve it in 100.0ml
of purified water by using magnetic stirrer i.e. SOP.
5.3.4.1.3
Add 20.0ml of 0.1M
silver nitrate and shake.
5.3.4.1.4
Use 1.0ml of
bromothymol blue solution R1 as indicator.
5.3.4.1.5
Set titration
apparatus.
5.3.4.1.6
Titrate with 0.1M
sodium hydroxide, until colour is changed.
5.3.4.1.7
Note down the volume
used as shown in Annexure-3.
5.3.4.1.8
Take at least 3
readings and take average of it.
5.3.4.2 Blank
titration:
5.3.4.2.1
Take a flask and
add in it 100.0ml of purified water and add 20.0ml of 0.1M silver nitrate and
shake.
5.3.4.2.2
Use 1.0ml of
bromothymol blue solution R1 as indicator.
5.3.4.2.3
Set titration
apparatus.
5.3.4.2.4
Titrate with 0.1M
sodium hydroxide, until colour is changed.
5.3.4.2.5
Note down the
volume used as shown in Annexure-3.
5.3.4.2.6
Take at least 3
readings and take average of it.
5.3.4.3 Calculate
percentage purity.
5.3.4.4 Calculations:
5.3.4.4.1
After taking
average volume of both blank titration and sample titration. Calculate the
volume used by the examined substance by using formula:
Volume
used by substance = Blank titration - Sample titration.
5.3.4.4.2
For percentage
purity use formula:
%age
purity = volume used by substance x factor x 100
Weight of sample
5.3.4.4.3
Put values and
calculate %age purity.
5.3.5
Factor:
5.3.5.1 1ml
of 0.1M sodium hydroxide is equivalent to 18.02mg of theophylline C7H8N4O2.
5.3.6
Limit:
5.3.6.1 99.0%
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 /Theophylline: 2015, pp. 1010-1011.
7.2
The British
Pharmacopoeia. Vol V.,
Official Monograph /Qualitative Reactions and Tests: 2015, pp. 266-270.
8.0 ANNEXURES:
Annexure 1: Observations
of Melting point apparatus.
Annexure 2: Observations
of Percentage Loss of drying by using oven.
Annexure 3: Observations
and calculations of assay.
Annexure:
1
Observations
of Melting point apparatus
|
Melting point apparatus
Sample = _____________
Time period = _____________
Average: _____________
Result: _________________
Remarks:
____________________________________________________________
_____________________________________________________________________
|
Annexure: 2
Observations
of percentage loss of drying by using Oven
|
Percentage
loss of drying by using Oven
Weight
of Sample = _____________
Time
period = _____________
Pressure=
_________________
Average % Loss of Moisture: _____________
Remarks:
_______________________________________________________________
|
||||||||||||||||||||||||
Annexure:
3
Observations
and calculations of assay
Indicator:
___________________
Weight
of sample: ____________
Factor:
_____________
Titrant:
_____________________
Sample titration
|
Sr.#
|
Initial volume (vi)
(ml)
|
Final volume (vf)
(ml)
|
vf-vi
(ml)
|
|
1.
|
|
|
|
|
2.
|
|
|
|
|
3.
|
|
|
|
Average volume: _________________
Blank titration
|
Sr.#
|
Initial volume (vi)
(ml)
|
Final volume (vf)
(ml)
|
vf-vi
(ml)
|
|
1.
|
|
|
|
|
2.
|
|
|
|
|
3.
|
|
|
|
Average volume: _________________
Calculations:
Volume used by substance = Blank
titration – Sample titration.
%age purity = volume used by
substance x factor x 100
Weight of sample
Result:
____________________________________________________________________
9.0 ABBREVIATIONS:
|
Abbreviation
|
Expanded Form
|
|
SOP
|
Standard
operating procedure
|
|
&
|
And
|
|
No.
|
Number
|
|
Ltd.
|
Limited
|
|
QCA
|
Quality
control active ingredient
|
|
F
|
Format
|
|
Q.C
|
Quality
control
|
|
Vol
|
Volume
|
|
BP
|
British
Pharmacopoeia
|
|
g
|
Grams
|
|
ml
|
Milliliter
|
|
h
|
Hours
|
|
Min
|
Minutes
|
|
ppt
|
Precipitates
|
|
oC
|
Degree
centigrade
|
|
mg
|
Milligram
|
|
M
|
Molar
|
|
vi
|
Initial
volume
|
|
vf
|
Final
volume
|
|
%
|
Percentage
|
|
g/L
|
Grams
per liter
|
|
R
|
Reagent
|
|
Ti
|
Initial
temperature
|
|
Tf
|
Final
temperature
|
|
Temp.
|
Temperature
|