TITLE
Assessment
of Quality of Tablets and Capsules
AIM
1. To examine the
shape, colour, diameter, thickness and/or other physical characteristics.
2. To measure the
uniformity of diameter, thickness and hardness of tablets.
3. To determine
the tablet friability.
4. To determine
the uniformity of weight of tablets and capsules.
5. To discover the
content of ibuprofen (assay).
DATE OF EXPERIMENT
21st November 2016
INTRODUCTION
Tablets and capsules are the example of the oral dosage form
used. Like all other dosage forms, they are
subjected to those pharmacopoeial standards dealing to the “added substances”
respecting their toxicity, interference with analytical methods and more. There
are certain procedures that is applied specifically to tablets and capsules and
they are designed to ensure that a tablet or a capsule exerts its full
pharmacological actions. Furthermore, they also to determine the uniformity of
the physical properties of the official tablet or capsule. These standards are
found in the British Pharmacopoeia and United Pharmacopoeia and they include,
uniformity of diameter, uniformity of weight (mass), content of active
ingredient, uniformity of content, friability, disintegration and dissolution.
There are a number of quality control procedures that is widely applied but are
not defined by the pharmacopoeias such as the thickness, and hardness.
In this assessment, there are five
experiments conducted:
1.
Examining the
characteristics of tablets and capsules.
2.
Testing the uniformity
of diameter, thickness and hardness.
3.
Testing the tablet
friability
4.
Testing the uniformity
of weight of tablets and capsules.
5.
Content of ibuprofen
(assay)
Experiment 1: Physical Appearance
Procedures:
1)
One tablet and capsule were
selected randomly from the provided samples. The shape, colour, diameter,
thickness and other physical characteristics were examined and determined for
the samples chosen.
Results:
Characteristics
|
Tablet
|
Capsule
|
Shape
|
Oval
|
Cylindrical
with hemispherical ends
|
Colour
|
Pink
|
Red
and Black
|
Diameter
|
1.8
cm
|
0.6
cm
|
Thickness
|
0.5
cm
|
-
|
Other physical
characteristics
|
Brand
– APP
Weight
– 250 mg
|
Brand
– AMPILLIN
Weight
– 250 mg
Length
– 1.7 cm
|
Experiment 2: Uniformity of diameter,
thickness and hardness
Procedures:
1.
10 tablets are selected
and carried out tests for uniformity of diameter, thickness and hardness using
the Tablet Testing Instrument (PHARMATEST PTB 311)
2.
The deviation of
individual unit from the mean diameter should not exceed ±5% for tablets with
diameter of less than 12.5 and ±3% for diameter of 12.5mm or more.
Results:
Tablet
|
Thickness
(mm)
|
Diameter
(mm)
|
Hardness
(N)
|
Deviation
of diameter (%)
|
1
|
5.45
|
13.16
|
113.80
|
0.228
|
2
|
5.48
|
13.11
|
150.01
|
-0.152
|
3
|
5.50
|
13.11
|
150.01
|
-0.152
|
4
|
5.47
|
13.12
|
137.08
|
-0.076
|
5
|
5.42
|
13.12
|
122.30
|
-0.076
|
6
|
5.45
|
13.11
|
143.55
|
-0.152
|
7
|
5.33
|
13.17
|
138.19
|
0.305
|
8
|
5.47
|
13.14
|
203.78
|
0.076
|
9
|
5.44
|
13.13
|
175.32
|
0.000
|
10
|
5.48
|
13.12
|
118.98
|
-0.076
|
Mean:
|
5.45
|
13.13
|
145.30
|
Formula for deviation =
x100%
x100%
The tablets are
manufactured by compression of the powder with force. So the thickness of
tablet depends on the amount of force applied during the compression to produce
the tablet. When larger force is applied, the tablet will be more compact and
thinner. A compact tablet will takes a longer time to dissolve and
disintegrate, so the absorption of drug by our body will be slower. If the
tablet is thick then it might break easily because the particles are not
compressed to compact. This cause the tablet couldn’t survive the whole
manufacturing process or might break before use by patients. Therefore it is
very important to achieve the optimum thickness for the tablet. In this
experiment, we used Tablet Testing Instrument (PHARMATEST PTB 311) to measure
the thickness, diameter and the hardness of the tablet. The mean thickness of
the tablet from the result of the experiment is 5.45mm. The mean diameter for the
tablets in the experiment is 13.13mm, so the tolerance for the tablets
deviation of individuals unit from the mean diameter must not exceed ±3%. From
the result table, it shows that the deviation of the individual unit does not
exceed ±3%, the deviation at most only 0.305%. Thus, we can confirm that the
tablets have uniform diameters.
Experiment 3 : Tablet friability
Procedures
:
1. 10 tablets were selected and weighed.
2. All tablets were put into the drum of the tablet
abration and friability tester. The rate of rotation was set to 25 rpm, time
to 10 minutes and the operation was started.
3. At the end of operation, all the tablets were removed
and the dust or powder on the tablets was cleaned by using brush. The tablets
were reweighed. The percentage loss of weight was determined.
Results
:
Original weight of 10 tablets
|
5.7811g
|
Weight of 10 tablets after the test
|
5.7583g
|
Weight of loss
|
0.0228g
|
Percentage loss of weight
|
 |
Discussion
:
The objective of testing the
friability of tablet is to ensure the stability of tablets during collision in
the bottle. To do this, the tablet abration and friability tester is used as a
standard to test the tablet friability. During the test, the dust and powder on
the tablets were cleaned with brush before reweighing for the second time to
determine the loss of weight. This is a precaution to ensure the accuracy of
the results.
According
to the results, only 0.39% of the weight was lost after the friability test.
Since the percentage of lose weight does not exceed 1%, hence, we can say that
the friability of tablets is satisfactory.
Experiment 4:
Uniformity of weight of tablets and capsules
Procedures :
Tablets
1.
20 tablets from previously selected at random
were weighed and the average weight was determined.
2.
Then, the tablets were individually being
weighed and the percentage deviation of its weight from the average weight was
determine for each tablet.
Capsules
1.
20 capsules were selected at random.
2.
One capsule was weighed. Capsule was opened
and the content was removed completely as possible. The emptied shell was
weighed. The net weight of its contents was determined, that was by subtracting
the weight of the shells from the weight of the intact capsule.
3.
The procedure was repeated with other 19
capsules.
4.
The average net weight from the sum of the
individual net weights was determined.
5.
The percentage deviation from the average net
weight for each capsules was determined. The deviation of individual net weight
should not exceed the limits given below.
Results :
Tablet
No.
|
Weight of
tablet (g)
|
Deviation
|
|
Weight
(mg)
|
Percentage
(%)
|
||
1.
|
0.6427
|
+0.7
|
0.11
|
2.
|
0.6293
|
-12.7
|
1.98
|
3.
|
0.6345
|
-7.5
|
1.17
|
4.
|
0.6092
|
-32.8
|
5.11
|
5.
|
0.6362
|
-5.8
|
0.90
|
6.
|
0.6285
|
-13.5
|
2.10
|
7.
|
0.6636
|
+21.6
|
3.36
|
8.
|
0.6331
|
-8.9
|
1.39
|
9.
|
0.6458
|
+3.8
|
0.59
|
10.
|
0.6449
|
+2.9
|
0.45
|
11.
|
0.6686
|
+26.6
|
4.14
|
12.
|
0.6426
|
+0.6
|
0.09
|
13.
|
0.6416
|
-0.4
|
0.06
|
14.
|
0.6324
|
-9.6
|
1.50
|
15.
|
0.6330
|
-0.9
|
0.14
|
16.
|
0.6305
|
-11.5
|
1.79
|
17.
|
0.6471
|
+5.1
|
0.79
|
18.
|
0.6690
|
+2.7
|
0.42
|
19.
|
0.6405
|
-1.5
|
0.23
|
20.
|
0.6663
|
+24.3
|
3.79
|
Average weight of tablet = total weight of 20 tablet / 20
Average weight = 12.8394g / 20
= 0.6420g
Deviation in percentage is calculated using
the formula below:
Deviation (%) = (weight of individual tablet) – (average weight of tablet) X 100%
Deviation (%) = (weight of individual tablet) – (average weight of tablet) X 100%
Average
weight of tablet
Number of
tablets have percentage of deviation ±5.0 = 19
Number of tablets have percentage of deviation ±10.0 = 1
Number of tablets have percentage of deviation ±10.0 = 1
Capsule
No.
|
Weight of capsule(g)
|
Weight of capsule shell (g)
|
Net weight of capsule (g)
|
Deviation
|
|
Weight (mg)
|
Percentage (%)
|
||||
1.
|
0.4688
|
0.0748
|
0.3940
|
+4.6
|
1.18
|
2.
|
0.4680
|
0.0733
|
0.3947
|
+5.3
|
1.36
|
3.
|
0.4604
|
0.0816
|
0.3788
|
-10.6
|
2.72
|
4.
|
0.4708
|
0.0759
|
0.3949
|
+5.5
|
1.41
|
5.
|
0.4718
|
0.0764
|
0.3954
|
+0.6
|
0.15
|
6.
|
0.4756
|
0.0804
|
0.3952
|
+5.8
|
1.49
|
7.
|
0.4748
|
0.0799
|
0.3949
|
+5.5
|
1.41
|
8.
|
0.4557
|
0.0743
|
0.3814
|
-0.8
|
0.21
|
9.
|
0.4803
|
0.0795
|
0.4008
|
+11.4
|
2.93
|
10.
|
0.4674
|
0.0797
|
0.3877
|
-1.7
|
0.44
|
11.
|
0.4726
|
0.0776
|
0.3950
|
+5.6
|
1.44
|
12.
|
0.4742
|
0.0810
|
0.3932
|
+3.8
|
0.98
|
13.
|
0.4669
|
0.0767
|
0.3902
|
+0.8
|
0.21
|
14.
|
0.4569
|
0.0819
|
0.3750
|
-14.4
|
3.70
|
15.
|
0.4644
|
0.0786
|
0.3858
|
-3.6
|
0.92
|
16.
|
0.4596
|
0.0768
|
0.3828
|
-6.6
|
1.69
|
17.
|
0.4614
|
0.0823
|
0.3791
|
-10.3
|
2.65
|
18.
|
0.4720
|
0.0775
|
0.3945
|
+5.1
|
1.31
|
19.
|
0.4613
|
0.0790
|
0.3823
|
-7.1
|
1.82
|
20.
|
0.4658
|
0.0735
|
0.3923
|
+2.9
|
0.74
|
Net weight
of 20 capsules: 7.7880g
Average net weight of capsule = net weight of 20 capsules/ 20
Average net weight of capsule = net weight of 20 capsules/ 20
Average net weight = 7.7880g / 20
= 0.3884g
Deviation in percentage is calculated using
the formula below:
Deviation (%) = (net weight of individual capsule) – (average net
weight of tablet) X 100%
Average
net weight of tablet
Number of capsules
have percentage of deviation ±5.0 = 20
Number of capsules have percentage of deviation ±10.0 = 0
Number of capsules have percentage of deviation ±10.0 = 0
Discussion:
Based
on the experiment, the uniformity of weight of
tablets and capsules were determined respectively in order to make sure that
the dosage units are consistent. The average weight of the tablets obtained was
0.6420 g. Since the average weight obtained is more than 250 mg, minimum 18
tablets did not deviate from 0.6420 g by 5 %. Maximum 2 tablets did not deviate
from 0.6420 g by 10 %. The uniformity of the tablets weighed had minimal
deviation between the range and fall within the range limit of weight. The
average weight obtained for the capsules was 0.3894 g. Since the average weight
obtained is more than 300 mg, minimum 18 capsules did not deviate from 0.3894 g
by 7.5 % and maximum 2 capsules did not deviate from the average weight by 15
%. The uniformity of the capsules weighed had minimal deviation and fall within
the range limit of weight. Therefore, all the tablets and capsules passed the
test conducted and both are considered as a successful batch respectively.
Besides, the results of the test of
uniformity of weight for capsules may not be that accurate as there is might be
some powder left in the capsules when they were emptied from the shells. As a
precaution, the shells of capsules should always be completely emptied before
weighing in order to increase the accuracy of result.
Questions
1. What are the objectives of the tests for uniformity of diameter and uniformity of content?
1. What are the objectives of the tests for uniformity of diameter and uniformity of content?
To identify the uniformity of diameter, thickness and hardness for 10
samples of tablet. To test the ability for tablet to withstand sufficient mechanical
strength and fracture/ erosion during manufacturing and handling.
2. State the types of tablets and capsules that must be tested for uniformity of diameter and uniformity of content.
All
the uncoated and coated tablets except the enteric tablets, film-coated tablets and
sugar-coated tablets. Whereas, the uniformity of content tests normally involves
single dose preparations. Tablets and capsules included are coated tablets, others than film-coated tablets containing 50mg or more of an active
ingredient that comprises 50% or more of one tablet. Tablets or capsules have
active ingredients less than 5% are needed. Liquid-filled soft capsules, solids
packaged in single-unit containers with or without added substances and
solutions for inhalation packaged in glass or plastic ampules are not
applicable for testing uniformity of content.
3.
Why is it important
that tablets and capsules have uniform weight and content?
To ensure accurate and consistent dosage form to
be administered by patients. The safety and efficacy of drug products can be
guaranteed when their quality is reliable and reproducible from batch to batch.
4.
Give reasons for the
non-compliance to test for uniformity of weight.
The reasons for non-compliance to test for uniformity of
weight are uneven feeding of granules into the die and due to irregular
movement of the lower punch that cause variation in capacity die space. This result in unsatisfactory mix of ingredients at
blending stage, and segregation of compound in
formulation is also can happen.
5.
Explain why is it
beneficial for any tablets or capsules to have distinctive or identifying features.
Differences in features may
affect patient compliance and acceptability of medication regimens. It could
prevent medication errors when patients could
mistaken having the same tablet twice if the features of medications given are
similar.
Experiment 5 :
Content of ibuprofen (assay)
Procedures :
1.
20 Ibuprofen Tablets
previously selected at random were weighed and powdered.
2. A quantity of powder
containing 0.5g ibuprofen were extracted with 20ml chloroform for 15 minutes
and was filtered through sintered glass crucible (BS Porosity No. 1).
3. The residue were washed
with 3 . 10 ml chloroform and the combined filtrate were gently evaporated just
to dryness in a current of air. The residue were dissolved in 100ml with
ethanol (96%) previously neutralized to phenolphthalein solution.
4. The solution was
titrated with 0.1 M sodium hydroxide to end point with phenolphthalein solution
as the indicator. The content of ibuprofen was calculated if each ml of 0.1 M
sodium hydroxide is equivalent to 0.002063 g of C13H18O2.
Results
:
Calculate the powder of
ibuprofen that contain 0.5g active ingredients of ibuprofen:
Weight
of powder of ibuprofen = 10.97g
1
ibuprofen tablet contains 400mg active ingredients of ibuprofen
20
ibuprofen tablets contain 20 x 400mg = 8000mg (8g) of active ingredients of
ibuprofen.
8g
ibuprofen contain in 10.97g of tablet powder
0.5g
ibuprofen contain in
= 0.69g of tablet powder.
= 0.69g of tablet powder.
Thus,
0.69g of tablet powder was weighed and dissolved in 20ml of chloroform.
Calculate the weight of
content of ibuprofen after titration:
C13H18O2 + NaOH = C12H17COONa
+ H2O
Volume of sodium hydroxide used = 14ml
Given
that 1mL of 0.1M sodium hydroxide is equivalent to 0.02063g C13H18O2,
So,
the weight of Ibuprofen in the tablet is 14 x 0.02063g = 0.289g.
Percentage of standard deviation =
x 100%
x 100%
= 
x 100%
x 100%
= 57.8%
Discussion :
From the calculation, we obtained a
standard deviation of 57.8%. Based on the value given by British Pharmacopoeia
(B.P.), the standard deviation accepted is between 90%-110% which proved that
some errors occurred during the experiment because the percentage of standard deviation
obtained from experiment is lower than the accepted value.
Firstly, some of the ibuprofen powder might left behind during
weighing and filtration process. The powder might stick at the weighing boat
when transferred to the conical flask and filter paper where the residue is not
being filtered completely before we proceed to the next step. Then, the content
of ibuprofen in powder given might be inaccurate or the ibuprofen tablets used
were expired, these might cause the reduced in amount of ibuprofen. Another error might occur when drying the
filtrate. The solution may not dry completely, causing to inaccurate results of
mass of ibuprofen. In addition, error would occur during the titration with
sodium hydroxide. This is because we titrated too fast and missed the first
volume of sodium hydroxide to change the colourless solution changed to pink
colour. To avoid this, we should titrate slowly with drop by drop because we
were not sure about the volume needed.
CONCLUSION
To design drugs with similar size and
shape so that the patients do not confuse, the uniformity of the diameter is
important. The thickness of the tablets
is important in order to package the tablets either in blister or plastic
container. The hardness of the tablets is important in order to ensure the
drugs or tablets have effective hardness that will makes them dissolve in
dissolution, but cannot easily break due to any pressure or forces applied to
them.
REFERENCES
2.
http://www.pharmacopeia.cn/v29240/usp29nf24s0_m39890.html
