TITLE
: THE EFFECT OF DIFFERENT AMOUNT OF PEG ON THE PHYSICAL CHARACTERISTICS OF
SUPPOSITORY
INTRODUCTION
:
Suppository is a small solid
preparation shaped to be inserted into the orifices of the body other than oral
cavity. This preparation is usually inserted in the rectum, vagina and urethra.
Suppository are usually medicated and solid at room temperature but melts at
body temperature. Medicament that are being incorporated in the suppository
bases are usually intended to give the patient either local or systemic effect.
Suppositories are usually being used to relief constipation, pain, itching and
inflammation.
Commonly used suppository bases are
Theobroma oil, glycerinated glycerine hydrogenated vegetable oil and
polyethylene glycol. In this experiment, we are using polyethylene glycol (PEG)
as the suppository base. PEG is being used as they are chemically stable,
non-irritating, miscible with water and mucus secretion. The advantage of using
PEG is that they do not melt at body temperature and it dissolve to provide a
prolonged released than Theobroma oil.
OBJECTIVES
:
1. To
calibrate suppository mould with EG before preparing medicated suppositories.
2. To
determine the effect of different compositions of PEG base on the physical
characteristics of suppositories.
APPARATUS
:
Analytical
balance
Water
bath at 37ºC
Hotplate
4
× 50 mL beaker
1
× 5 mL pipette and pipette bulb
1
× 5 mL measuring cylinder
2
× suppository mold set
Spatula
4
× weighing boats
2
× glass rods
MATERIALS
:
Polyethylene
glycol (PEG) 1000
Polyethylene
glycol (PEG) 6000
Paracetamol
Distilled
water
Liquid
paraffin
PROCEDURES
:
a)
Calibration
of Suppository Molds with PEG Base
10g
of the proportions between PEG 1000 and PEG 6000 were being used for the
calibration experiment.
Ingredients
|
Percentage
|
Weight
basis
|
PEG 1000
|
60%
|
6g
|
PEG 6000
|
40%
|
4g
|
1. A
clean and dry mold was took out and the mold was ensured not to be lubricated.
2. PEG
1000 was melt on the hot plate. After that, the melt PEG 1000 was moved away
from the hot plate for a short period to reduce its temperature and mixed with
another PEG.
3. The
mixture was removed completely from the hot plate and allowed to cool before
being poured into the mold.
4. The
cavities in the mold were being overfilled with the mixture. It was then left at
room temperature until solidified.
5. A
hot spatula was being used to remove the excess and the suppositories were
remove from the mold.
6. The
suppositories were weighed and the total weight was recorded. The average
suppositories weight was calculated.
b)
Preparation
of Paracetamol Suppositories
1. Saturated
stock of paracetamol was being prepared by adding 10g of paracetamol in 15 mL
of distilled water.
2. Paracetamol
suppository (10g) was being prepared by using the following formulation:
Suppository
|
PEG 1000 (g)
|
PEG 6000 (g)
|
Paracetamol stock solution (mL)
|
Total (g)
|
I
|
9
|
0
|
1
|
10
|
II
|
6
|
3
|
1
|
10
|
III
|
0
|
9
|
1
|
10
|
3. One
type of PEG was left to melt on the hot plate, then reduce it and mixed with
another PEG.
4. The
mixture was removed from the heat and allowed to cool before being poured into
the mold.
5. The
cavities in the mold were being overfilled with the mixture and left to
solidified at room temperature.
6. The
excess was then removed by using a hot spatula. The suppositories were then
removed from the mold.
7. The
shape, texture, and colour of the suppositories were being observed.
8. Each
of the suppositories were being placed in a separate beaker containing distilled
water (10 mL and pre-warmed at 37ºC).
9. The
time for the suppositories to melt was recorded.
RESULT
Description/Suppository
|
I
|
II
|
III
|
Shape
|
Bullet
|
Bullet
|
Bullet
|
Texture
|
Greasy
|
Slightly greasy
|
Smooth
|
Colour
|
Clear white
|
Cloudy white
|
Solid white
|
Time taken to melt(min)
|
49.00min
|
32.49min
|
42.03min
|
DISCUSSION
1. Describe
the important of calibrating suppository mould before preparing medicated
suppository.
The
experiment is started firstly by calibrating the suppository mould. It is
important for the suppository mould to be calibrated to ensure accurate dosing.
Sometimes there are slight differences between moulds and even the cavities
within a mould. The mould is calibrated using the base alone, which in this
experiment, the bases used are PEG 1000 and PEG 6000. The products are weighed
and the mean weight is taken as true capacity. The mould used produce six
suppositories, the weight of the product is 5.906g and the mean weight (which
is assumed as the true capacity) is 0.9843g.
2. Compare
the physical appearance of suppositories that are formed and discuss.
The
shape of the suppositories produced is all bullet-shaped because of the type of
the mould used. Based on the observation, the difference in the composition of
the base gives varieties to the physical appearance of each suppository.
From
suppository I to III, the composition of PEG 6000 is increasing while PEG 1000
is decreasing. When the composition of PEG 1000 is high, the suppositories
produced are softer and the strength is low. The melting point of PEG 1000 is
37-40⁰C. It will melt when
inserted into rectum, which is at the human body temperature, 37.5⁰C.Suppository I is greasy
and the smoothness is high.
Suppositories
which contain high composition of PEG 6000 is a bit harder and not greasy. The
strength of these suppositories is greater. This is because increasing content
of PEG 6000 increases the number of hydrogen bonds between the molecules. The
melting point of PEG 6000 is 60-63⁰C,
thus theoretically the suppositories with high composition of PEG 6000 is not
easily melt at human body temperature. Suppository III is less greasy and the
smoothness is low. The intensity of white colour of the suppositories, from
suppository I to III, is increasing. This is due to the increasing content of
PEG 6000 which gives the whitish properties to the product.
3. Plot
a graph of time required to melt the suppository vs. the amount of PEG 6000 in
the formulation. Compare and explain the results.
PEG amount (g)
|
0
|
3
|
9
|
Time (min)
|
49.0
|
32.49
|
42.03
|
Graph
1
The
graph shows the time required for suppositories to melt versus the amount of
PEG 6000 in the formulation. The melting point was influenced by the molecular
weight of the PEG. The bigger the molecular weight, the higher the melting
point. Generally, PEG 1000 has a lower melting point compared to PEG 6000.
Melting point of PEG of the same molecular weight will vary as their amounts
were manipulated.
In this experiment, suppository III has a
higher melting point compared to Suppository II because it has more amount of
PEG 6000. The melting point gathered from the experiment for suppository III is
49.00 minutes compared to 32.49 minutes for suppository II.
However,
the suppository II shows a lower melting point compared to the suppository I
although it contains more PEG 6000 which is 42.03 minutes. This could happen
due to some errors during the experiment. Firstly, the formulation were heated
too long during the compounding. Correspondingly, the melting point of the
suppository will be affected. Other than that, the temperature of the water
bath was not kept constant. Finally, the recorded time taken for the
suppositories to melt were the reading when they were completely dissolved. We
were supposed to take the time taken as soon as the suppositories started to
melt.
Thus,
the data collected has been biased from the theoretical data and some
precaution steps should be taken before doing this experiment. The temperature
of water bath should be keep constant by monitoring the temperature
continuously and the time taken for the suppositories to dissolve should be
start as soon as the suppository being place in the beaker containing distilled
water and stop as soon as it start to dissolve.
4. Describe
function(s) of each ingredients used in the suppository formulation.
The
ingredients used in the suppository formulation include paracetamol and
Polyethylene Glycol (PEG) polymers which is PEG 1000 and PEG 6000. The
paracetamol acts as the active ingredient in the preparation. It is the main
substance in the drug formulation that are used intended to furnish
pharmacological activity in the treatment of disease or to affect the function
of the body. Next, both Peg 1000 and PEG 6000 work as suppository bases. PEG
have received much attention as suppository bases because they possess many
desirable properties. They are chemically stable, non-irritating, miscible with
water and mucous secretions, and can be formulated, either by moulding or
compression, in a wide range of hardness and melting point. In this experiment,
the formulas of the suppository contained various proportions of PEG 1000 and
PEG 6000 in order to yield a finished product that can be tested for hardness
and dissolution time. The desired solidity of final products can be adjusted by
mixing appropriate molecular weight and suitable ratio of PEG.
CONCLUSION
The different amount of combination of PEG 1000 and PEG 6000 in the
suppository preparation affects the physical characteristics e.g. greasiness
texture, and shape of the suppository as well as the rate of release of the
active ingredient.
REFERENCE
2. Suppository. https://www.drugs.com/dict/suppository.html
3. Preparation of suppositories. http://pharmlabs.unc.edu/labs/suppository/bases.htm
3. Preparation of suppositories. http://pharmlabs.unc.edu/labs/suppository/bases.htm
PREPARED BY
Prasannah a/p Govindan A153129
Wan Nur Husnul Khatimah binti Wan Mansor A152352
Nur Shahirah binti Ishak A153147
Nina Athirah binti Hasinin A152865
Tasneem bt Mahayudin A152348
Mohd Faiz bin Abd Latif A153049
