Objectives
·
Disintegration test :
To determine the time taken needed for tablet to
disintegrate and whether it disintegrates properly when placed in a liquid
medium under the experimental condition in this experiment.
·
Dissolution test :
To determine the amount of active ingredient(s) released
from a solid oral dosage form, using a known volume of dissolution medium
within a predetermined length of time.
Introduction
Dosage
performance test is a series of tests that is composed of the specification in
a United States Pharmacopeia (USP) dosage form monograph. An orally
administered, non-solution dosage form is usually satisfied by either a dissolution
or disintegration process. Disintegration test is only applicable
for uncoated tablets, sugar coated tablets, enteric-coated tablets,
soluble tablets, dispersible tablets, hard and soft capsules and lastly,
enteric capsules. Complete disintegration is defined
as that state in which any residue of the unit, except fragments of insoluble
coating or capsule shell, remaining on the screen of the test apparatus or
adhering to the lower surface of the disc, if used, is a soft mass having no
firm core. At the same time, dissolution testing is used
to provide critical in vitro drug release information for both quality control
purposes.
Materials
and Apparatus
Disintegration
Test
·
6 tablets
·
Disintegration medium - water
·
Beaker
·
Disintegration machine - Discs, mechanical device that
controls up-down movement, device that control temperature
Dissolution
Test
·
Ibuprofen tablets
·
Dissolution medium
·
Ibuprofen standard solution
·
Dissolution tester
·
Spectrophotometer
·
Filter funnel
·
10ml measuring cylinder
·
Dropper
·
50ml volumetric flasks
·
Weighing boat
·
Electronic balance
Procedures
Disintegration test for sugar-coated tablets
1. The
apparatus is set up for disintegration test according to its operation manual.
2. The
temperature of the disintegration medium is ensured to be at 37 ± 2°C.
3. The
time is set to 60 minutes. Then, one tablet is introduced in to each tube and
the disk is added into each one. Operation is started.
4. The
tablet in each tube is checked at the end of the operation.
5. New
tablets are used to replace the tablets that did not disintegrate and 0.1M
hydrochloric acid is used instead of water.
Dissolution test for tablets
1.
Dissolution vessel is filled with the buffer solution to 900
ml mark. The temperature is set to 37°C.
2.
The temperature of the
dissolution medium is ensured to be 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. The basket
assembly is lowered into position in the vessel and the operation is started.
5.
10 ml samples of the dissolution medium is withdrew using
syringes after 30 minutes and the solution is filtered using suitable filter.
6.
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 is
diluted to 25 ml with dissolution medium in separate 25 mL of volumetric
flasks.
8.
The absorption of both solutions was measured in a 1
cm cell at a wavelength of 221 nm.
9.
The percentage
of amount of ibuprofen dissolved was
calculated using the following formula:
|
At/As × W/50× P × 900 × 2/25 × 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.
Result
Disintegration Test
|
Paralgin Tablets
|
Disintegration test with water
|
Time needed to fully disintegrate
|
|
6
|
Pass
|
1.96 minutes
|
Dissolution Test
Absorbance
of sample solution: 0.683
Absorbance
of standard solution: 2.016
Percentage
amount of ibuprofen dissolved = At/As ×
W/50× P × 900 × × 100/200
=
0.683/2.016 x 10/50 x 0.98 x 900 x 2/25 x0.5 =
9.56%
Discussion
For disintegration test, a paralgin tablet
needs 1.96 minutes to disintegrate fully. Since the tablet disintegrates not
more than one hour in water medium, hence the result has met the standard
result of the experiment. However, in human body, many parameters such as pH
and motility of GI tract and many others should be considered if the experiment
was meant to really imitate the environment in the body. Despite that, this
test is still usable and effective in pre-formulation stage so as to filter and
obtain the drug candidates.
In this experiment, there are a few
precautions that one should keep in mind. Firstly, when the formulation has
reached the time limit set, squish it to enable the content to be in contact
with the water. If the first batch of tablet did not meet the requirement, then
the test needs to be repeated by using 0.1M HCl to replace water. Lastly, it
must be ensured that the water in the beaker is heated up sufficiently.
As for dissolution test, the reading
of spectrophotometer for standard solution and sample solution are 2.016 and 0.683
respectively. According to calculation, the percentage amount of ibuprofen
dissolved is 9.56%. To be able to comply with the British Pharmacopoeia, the
percentage amount of tablet dissolved must at least be 75%. Hence, the tablet
does not comply with it.
This
may be due to the errors which occurred during the experiment. Firstly, the
temperature of the dissolution medium might not be maintained at 37 degree
Celcius. Next, when the sample solution is
transferred into the volumetric flask, it is not filtered by using the filter. Hence, there
will be some small undissolved ibuprofen tablet fragments in it. This in turn
results in wrong reading of absorbance. Another error might be the expiration
of tablet. Expired tablet may have altered physicochemical properties and
causing different result. Parallax error may also occur when measuring the
solution in measuring cylinder and other apparatus. Precaution steps should be
taken to avoid these errors so that accurate result can be obtained.
Conclusion
As
the paralgin tablet has disintegrated within one hour in the water medium, this
shows that the tablet has met the standard result for this experiment. For the
dissolution test, the ibuprofen tablet did not achieve the standard result as
less than 75 % only had dissolved.
