Experiment 4:
Dosage performance tests
Disintegration test for sugar-coated
tablets
Apparatus and Materials:
- 6 different types of film-coated tablets
- Basket-rack assembly containing 6 open-ended transparent tubes, held in a vertical position
- Discs (when specified)
- A beaker (1 litre) to contain the immersion fluid
- Mechanical device to control up-down movement (28-32 cpm)
- Device to control temperature (36-38°C)
Procedure:
1. The apparatus for the disintegration test is set
up according to its operation manual.
2. The temperature of the disintegration medium
which is water is ensured to maintain at 37 ±
2°C.
3. The time for operating the apparatus is set to
60 minutes. One tablet is introduced into each
tube and
the disk is added into each tube and the operation is started.
4. The tablet is checked in each tube at the end of
the operation.
5. Tablets are complied with the test if all 6 tablets
disintegrate in 60 minutes.
6. The test is repeated by using 6 new tablets if
there is any tablet that does not disintegrate in
the disintegration medium. The water is replaced
with 0.1M hydrochloric acid. Tablets are
complied with the test if all 6 tablets
disintegrate in the acidic medium.
Results:
|
Tablets
|
Disintegration test with water
|
|
1
|
Pass
|
|
2
|
Pass
|
|
3
|
Pass
|
|
4
|
Pass
|
|
5
|
Pass
|
|
6
|
Pass
|
Discussion:
The
disintegration test for the 6 tablets is succeeded. This is because the tablets
do not take more than 1 hour to disintegrate completely in the disintegration
medium which is the water which means there is no residue of the tablet except
fragments of undissolved coating which remains on the screen of the test
apparatus or, if any other residue remains, it consists of a soft mass having
no palpably firm, unmoistened core. A tablet with a good disintegration
property can attain the good absorption of the active ingredient.
Normally, the disintegration test is used
a simple test which helps in the preformulation stage to the formulator. To
identify the efficacy of the drug release, the
disintegration time can be modified for a rapid effect or for sustained release. The optimisation of manufacturing
variables, such as compressional force and dwell time can also be found out
through the disintegration test. Besides, this test is also a simple in-process
control tool to ensure uniformity from batch to batch and among different
tablets and the quality control of tablets. Hence, a good orally administered
drug can be produced to achieve its bioavailability.
However, there is some limitation
of the disintegration test. Disintegration test
cannot be relied upon for the assurance of bioavailability. Although the coated tablets dissolve in the
disintegration medium which is the water having pH7, the pH condition of the
gastrointestinal tract is not exactly pH7, for an example , the pH of the
stomach is pH2 to pH3. So, it does not have guarantee of clinical efficacy. If
the drugs do not disintegrate completely in the gastrointestinal tract, the
absorption of the active ingredient will also be affected. Therefore,
dissolution test is needed to be carried out to ensure the clinical efficacy of
the tablets.
Conclusion:
6 tablets
disintegrate completely in disintegration medium and this show that the
disintegration test is succeeded.
Reference:
Dissolution test for tablets
Apparatus and Materials:
- Dissolution vesse
- Buffer solution
- Dissolution mediu
- One Ibuprofen tablet
- Dry basket assembly
- Filter
- Volumetric flask
Procedure:
1. Each of the dissolution vessel is filled up with
the buffer solution to 900 ml mark and the
temperature
is set to 37°C.
2. The temperature of the dissolution medium
checked to ensure that it is maintained at 37 ±
0.5°C.
3. One Ibuprofen Tablet is placed into each dry
basket assembly.
4. The stirring speed is set to 150 rpm and the
basket assembly is lowered into position in the
vessel
and then the operation is started.
5. 10ml samples of the dissolution medium is
withdrawn from each vessel after 30 minutes for
analysis and the solution is filtered by using
suitable filter.
6. Sampling is done from a point half-way between
the surface of the dissolution medium and
the top
of the rotating basket, and not less than 10 mm from the wall of the vessel. The
volume
of aliquot withdrawn for analysis is replaced with an equal volume of same
dissolution
medium.
7. A standard solution of ibuprofen is prepared by
diluting 10.0 mg of ibuprofen reference
standard
to 50 ml with dissolution medium.
7. 2.0 ml of sample solution and 2.0 ml of standard
solution to 25 ml are diluted with
dissolution
medium in separate volumetric flasks.
8. The absorption of both solutions in a 1 cm cell
at a wavelength of 221 nm is measured.
9. The percentage amount of ibuprofen dissolved is
calculated by using the following formula:
At/As × W/50 × 2/25 × P × 900 × 25/2 ×
100/200
Where At = absorbance of sample solution
As
= absorbance of the standard solution
W
= weight of ibuprofen reference standard used.
P
= purity of ibuprofen reference standard.
10. The tablets are determined from the results
obtained whether they are complied with the
requirements
of the United States Pharmacopoeia.
USP limits: Not less than 75% of the stated amount
of C13H18O2 dissolved in 30 minutes.
Results:
At= 0.176
As= 0.057
W= 0.010g
P= 98/100
Calculation:
Percentage of the amount of ibuprofen dissolved
= At/As × W/50 × 2/25 × P × 900 × 25/2 × 100/200
= 0.176/0.057 × 0.01/50 × 2/25 × 98/100 × 900 ×
25/2 × 100/200
=0.2723%
Hence, the result show that the ibuprofen
tablet is not complied with the USP requirements.
Discussion :
Dissolution test is used to measure
the amount of active ingredient that has dissolved in a volume of dissolution
medium at the prescribed time, using an apparatus specially designed according
to the experimental parameters. From this experiment, the reading of absorbance of sample solution is 0.176
and absorbance of the standard solution is 0.057. After the calculation, the
percentage of the amount of the ibuprofen tablet dissolved is 0.2723%. It can
conclude that the ibuprofen tablet selected for this experiment is no complied
with the United States Pharmacoepia requirement which is less than 75% of the
stated amount of C13H18O2 dissolved in 30 minutes. The result is incorrect as
there is some errors occurred when carrying out the experiment.
The first error is the sampling is not done according to the instruction
which is taken from a point half-way between the surface of the dissolution
medium and the top of the rotating basket, and not less than 10 mm from the
wall of the vessel. This will affect the measurement of the absorbance of the
sample solution in the cell by the spectrophotometer. An accurate calculation of the percentage of the ibuprofen cannot be
obtained due to the incorrect spectrophotometer reading of the absorbance of sample solution. Hence, the
instruction must be followed strictly when carrying out the experiment to
obtain the accurate reading of the result.
Besides, there is some parallax error occurred in this experiment. When
carrying out the dilution and measurement of the solution, the eyes are not
placed in a position which is perpendicular to the calibration mark of the
volumetric flask and measuring cylinder. This will affect the concentration of
the sample and standard solution. The result of obtaining an accurate spectrophotometer reading will
also be affected. To overcome this situation, the one who handle this job
should always be reminded to place the eye position correctly when doing the
measurement using measuring cylinder or dilution using volumetric flask. A
white paper can also place behind the instruments to get a clearer vision to do
the measurement and dilution.
The dissolution
testing apparatus will also affect the result of the experiment. It may has excessive peculiarity of the agitator device or the velocity
of the rotating element is too high. This will create the external vibration
that may bring in energy into the system hence affecting flow patterns. This
may affect the tablet which does not dissolve thoroughly in the dissolution
medium. To solve this problem, the apparatus must be checked properly before
conducting the dissolution test.
Conclusion:
The reading of absorbance of sample solution is 0.176
and absorbance of the standard solution is 0.057. The percentage of the amount
of the ibuprofen tablet dissolved is 0.2723% which is not complied with the
United States Pharmacoepia requirement, stating that the percentage should not less
than 75% of the stated amount of C13H18O2 dissolved in 30 minutes. The result
is inappropriate.
References:
No comments:
Post a Comment