Title
Dosage performance tests
(A) Disintegration test for sugar-coated
tablets
Objective
To test dosage performance of
sugar-coated tablets by disintegration.
Date of Experiment
4th December 2014
Introduction
Disintegration
is a process that will produce smaller fragments of drugs, which results in
drug releasing process from tablets. Tablet disintegration
testing is used as a quality-assurance measure. It is not a true predicter of
how well the dosage form will release its active ingredient in vivo. The United
States Pharmacopiea (USP) sets standards for tablet disintegration testing. The
apparatus is relatively simple. It consists of a basket rack holding six
plastic tubes open at the top and bottom. The bottom is covered with a 10 mesh
screen. The rack is immersed in a suitable liquid at 37˚C. It moves up and down
at a specified rate. One tablet is placed into each tube and the time to
disintegrate and fall through the screen is noted.
Disintegration is achieved when there is no tablet
fragments remained on the screen. However, the coating fragment may remain. If
any other residue remains, it may consist of a soft mass having no palpably
firm, unmoisted core.
Apparatus
Spatula, disintegration apparatus.
Materials/chemical
Oralmet, Redon, Ettrocin, Mefa, Uphamol
Experimental Methods
1. The
disintegration apparatus is set up according to its operation manual.
2. The
medium for disintegration is water and the temperature is ensured at 37°+2°C.
3. The
time for this test is set to 60 minutes.
4. The
disintegration apparatus consists of 6 tubes, each tube is then introduced with
a tablet using spatula.
5. A
disc is added into each tube to avoid the tablets to floating out from the
tubes when it is raised and lowered down.
6. The
operation is started.
7. After
60 minutes, the tablets is checked in each tube.
8. Tablets
comply with the test if all 6 tablets disintegrate in 60 minutes. The test is
repeated using 6 new tablets but replacing the disintegration medium(water)
with 0.1M hydrochloric acid if there is any tablet that does not disintegrate.
Tablets comply with the test if all 6 tablets disintegrate in the acidic
medium.
(B) Dissolution test for tablets
Objective
To test the dosage performance of tablet by dissolution.
Introduction
Dissolution test is carried out using the specially
designed apparatus according to the experimental parameters. Dissolution
testing is the most important way to study the release of a drug from a solid
dosage form under in vitro conditions. It will affect the bioavailability of a
drug from a solid preparation. Like the disintegration test, the
dissolution test does not prove that the dosage form will release the drug in
vivo in a specific manner but it is one step closer to the absorption process.
Again the USP sets standards for the dissolution but often those suggested
procedures are modified by the manufacturer to meet the specific needs of the
product. This test is most often performed on products that have known
absorption problems or known poor solubility. It is also performed on sustained
or delayed release products such as enteric coated products.
This test requires
the solution to be tested for concentration of active ingredient over the time.
A dissolution profile is then constructed (Time vs Amount Dissolved) and this
is compared to the reference compound or standard for the dosage form in being
dissolved.
Apparatus
water bath, motor to regulate the basket speed,
cylindrical vessel, basket at temperature of 37±0.5̊C
Materials
Ibuprofen tablet, buffer solution, dissolution
medium
Procedures
1) Each of the dissolution vessels is filled up with
the buffer solution to 900ml mark. The temperature is set to 37̊ C.
2) The temperature of the dissolution medium is
checked. It is ensured at
37±0.5̊C.
3) One Ibuprofen tablet is placed into each dry basket
assembly.
4) The stirring speed is set to 150rpm. The basket
assembly is lowered into position in the vessel and the operation is started.
5) After 30 minutes, 10ml sample of the dissolution medium is
withdrawn
from each vessel for analysis and
the solution is filtered by using suitable filter. Sampling should be done from
a point half-way between the surface of the dissolution medium and the top of
the rotating basket, and not less than 10mm from the wall of the vessel. The
volume of aliquot withdrawn for analysis is replaced with an equal volume of
same dissolution medium.
6) A standard solution of ibuprofen is prepared by
diluting 10.0mg of ibuprofen reference standard to 50ml with dissolution
medium.
7) 2.0ml of sample solution and 2.0ml of standard solution
to 25ml is diluted with dissolution medium in separate volumetric flask.
8) The absorption of both solutions is measured in a
1cm cell at wavelength of 221nm.
9) The percentage amount of ibuprofen dissolved is
calculated using the following formula
At/As x W/100 x 2/25 x P x 900x 25/2 x 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) From the results obtained, the tablets are
determined whether it comply with
the requirements of the United State Pharmacopoiea.
USP limits: Not less than 75% of the stated amount of C13H1802
dissolved
in 30 minutes
Results
(A) Disintegration
test for sugar-coated tablets
All tablets are
disintegrated after 60 minutes
(B) Dissolution
test for tablets
Results
Solution
of Ibuprofen
|
Absorption
in 1cm cell at a wavelength of 221nm
|
Standard
|
0.758
|
Sample
|
0.481
|
Calculation
The
percentage amount of ibuprofen dissolved can be calculated using the following
formula:
At/As
x W/50 x 2/25 x P x 900x 25/2 x 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
After
30 minutes
The
percentage amount of ibuprofen dissolved
= 0.481 x 10 x 2 x 0.98
x 900
x 25 x 100
0.758
50 25 2 200
=55.97%
Discussion
In order for a drug to be absorbed from a solid dosage form after oral administration,
it must first dissolve in solution, followed by the break-up of the tablet; a
process known as disintegration. The higher the rate of disintegration, the
faster the drugs can be absorbed.
The disintegration test is a measure of the time required
under a given set of conditions for a group of tablets to disintegrate into particles which will pass through a mesh
screen. Generally, the test is used as a quality assurance tool for
conventional dosage forms. Disintegration process is achieved when no tablet
fragments remain on the screen. In this experiment, all tablets are
disintegrated in the water after 60 minutes. The limitation of this test is
that it does not mimic the condition of GIT. As such, there is no guarantee of
clinical efficacy. It is not applicable to tablets that must comply with
dissolution test.
Dissolution is the process by which a solid solute enters a
solution. In pharmaceutical industry, it may be defined as the amount of drug
substance that dissolves in solution per unit time under standardized
conditions of liquid/solid interface, temperature and solvent composition.
Dissolution is one of the most important quality control
tests performed on pharmaceutical dosage forms and is now used to predict bioavailability. In some cases, it
replaces clinical studies to determine bioequivalence. Dissolution behaviour of
drugs
has a significant effect on their pharmacological activity. Solid dosage forms may or may not disintegrate when they interact with
gastrointestinal fluid following oral administration depending on their design.
According to USP limits, it must not
less than 75% of the stated amount of C13H1802 dissolved
in 30 minutes. From the results obtained, the amount of ibuprofen dissolved is
less than 100%. The inaccuracy of results shows that the tablet does not pass
the dissolution test. This may happen due to some errors that occur during
experiment.
Conclusion
