chapter 7 formulation and evaluation of fast dissolving...
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Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
School of Pharmaceutical Sciences Shobhit University Meerut 119
7.0 FORMULATION AND EVALUATION OF FAST DISSOLVING TABLET
7.1 FORMULATIONOF FAST DISSOLVING TABLET
Solid dispersions SDG815, SDGK915, SD D815 and SD DK915were selected for formulation
of fast dissolving tablets. The composition and codes of formulations are shown in table7.1
to7.4.
Table 7.1: Composition and codes of SD G815fast dissolving tablets
Ingredient
(mg)
Formulation Codes
F1 F2 F3 F4 F5 F6 F7 F8 F9 F10
SD G815 - 180 180 180 180 180 180 180 180 180
Gliclazide 30 - - - - - - - - -
Sodium starch glycolate - 4 6 8 - - - - - -
Crosscarmellose - - - - 4 6 8 - - -
Kyron 4 6 8
Mannitol 50 10 10 10 10 10 10 10 10 10
Orange flavor 1 1 1 1 1 1 1 1 1 1
Magnesium stearate 2 2 2 2 2 2 2 2 2 2
Talc 4 4 4 4 4 4 4 4 4 4
Aspartame 1 1 1 1 1 1 1 1 1 1
Avicel PH 102 132 18 16 14 18 16 14 18 16 14
Total weight (mg) 220 220 220 220 220 220 220 220 220 220
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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Table 7.2: Composition and codes of SD GK915 fast dissolving tablets
Ingredient(mg) Formulation Codes
F11 F12 F13 F14 F15 F16 F17 F18 F19
SD GK915 180 180 180 180 180 180 180 180 180
Sodium starch glycolate 4 6 8 - - - - - -
Crosscarmellose 4 6 8
Kyron 4 6 8
Mannitol 10 10 10 10 10 10 10 10 10
Orange Flavor 1 1 1 1 1 1 1 1 1
Magnesium stearate 2 2 2 2 2 2 2 2 2
Talc 4 4 4 4 4 4 4 4 4
Aspartame 1 1 1 1 1 1 1 1 1
Avicel PH 102 18 16 14 18 16 14 18 16 14
Total weight (mg) 220 220 220 220 220 220 220 220 220
Table 7.3: Composition and codes of SD D815 fast dissolving tablets
Ingredient(mg) Formulation Codes
F20 F21 F22 F23 F24 F25 F26 F27 F28 F29
SD D815 - 120 120 120 120 120 120 120 120 120
Domperidone 20 - - - - - - - - -
Sodium starch glycolate - 4 6 8 - - - - - -
Crosscarmellose - - - - 4 6 8 - - -
Kyron 4 6 8
Mannitol 50 10 10 10 10 10 10 10 10 10
Mint Flavor 1 1 1 1 1 1 1 1 1 1
Magnesium stearate 2 2 2 2 2 2 2 2 2 2
Talc 4 4 4 4 4 4 4 4 4 4
Aspartame 1 1 1 1 1 1 1 1 1 1
Avicel PH 102 142 78 76 74 78 76 74 78 76 74
Total Weight (mg) 220 220 220 220 220 220 220 220 220 220
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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Table 7.4: Composition and codes of SD DK915 fast dissolving tablets
7.1.1 PREPRATION OF THE BLEND
Solid dispersion and mannitol were passed through sieve # 60. Avicel was passed through
sieve # 20 and all other ingredients were passed through sieve no. 80. Ingredients were blended
in a polybag.1
7.1.2 EVALUATION OF BLEND2
Various formulations and process variables were involved in mixing of ingredients and all
these can affect the properties of the blends produced. Various evaluation parameters of blends
tested are given below and data is represented in table7.7.
7.1.2.1 Bulk Density (ρb)
Bulk density is defined as the mass of powder divided by the bulk volume and is expressed as
g/cm3
. The bulk density of a powder primarily depends on particle size distribution, particle
shape and tendency of particles to adhere together. A standard procedure was followed to
determine the bulk density of blends. The blend was poured into a graduated cylinder. The
bulk volume and weight of powder was determined. The cylinder was dropped onto a hard
wooden surface three times from a height of 1 inch at an interval of 2 s. The bulk density was
calculated using the formula and is shown in table 7.7
ρb= M / Vb
where ρb= Bulk density
M = Mass of sample in g
Ingredient(mg) F30 F31 F32 F33 F34 F35 F36 F37 F38
SD DK915 120 120 120 120 120 120 120 120 120
Sodium starch glycolate 4 6 8 - - - - - -
Crosscarmellose - - - 4 6 8 - - -
Kyron 4 6 8
Mannitol 10 10 10 10 10 10 10 10 10
Mint Flavor 1 1 1 1 1 1 1 1 1
Magnesium stearate 2 2 2 2 2 2 2 2 2
Talc 4 4 4 4 4 4 4 4 4
Aspartame 1 1 1 1 1 1 1 1 1
Avicel PH 102 78 76 74 78 76 74 78 76 74
Total Weight (mg) 220 220 220 220 220 220 220 220 220
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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Vb= Bulk volume of blend in cm3
7.1.2.2 Tapped Density (ρt)
Tapped density can be defined as mass of blend in the measuring cylinder divided by its tapped
volume. The measuring cylinder containing a known mass of blend was tapped 20 times on a
hard wooden surface. The tapped volume occupied in the cylinder and the weight of the blend
was measured. The tapped density was calculated using the formula and represented in table 7.
ρt= M / Vt
where ρt= Tapped density
M = Mass of blend in g
Vt= Tapped volume of blend in cm3
7.1.2.3 Angle of Repose (θ)
Angle of repose indicates the frictional forces in a loose powder. It can be defined as the
maximum angle between the slope of pile of powder and its base. The Angle of repose was
determined using funnel method, designed by Newmann. The blend was poured through a
funnel that could be raised vertically until a specified cone height (h) was obtained. Radius of
the heap (r) was measured and angle of repose (θ) was calculated using the formula:
tan θ = h / r
Therefore θ = tan-1
h / r
Where θ = angle of repose
H = height of cone
R = radius of cone
The flow of materials is inferred by consulting the relationships showed in table7.5.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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Table 7.5: Angle of Repose as an indicator of powder flow
Angle of Repose (θ) Type of flow
<25 Excellent
25-30 Good
30-40 Passable
>40 Very poor
7.1.2.4 Compressibility Index (I)
The simplest way for measurement of flow of powder is its compressibility, an indication of
the ease with which a material can be induced to flow is given by compressibility index, which
is calculated as follows:
I = (ρt –ρb) / ρt ×100
Where ρt= Tapped density
ρb= Bulk density
The value below 15% indicates a powder with usually give good flow characteristics;
whereasabove 25% indicates poor flowability. The nature of flow is inferred by comparing the
data with the index showed in table 7.6.
Table7.6: Compressibility Index as an Indication of Powder Flow
Carr's Index (%)
Type of flow
15-21 Excellent
12-16 Good
18-21 Fair to passable
23-35 Poor
33-38 Very poor
>40 Extremely poor
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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7.1.2.5 Hausner ratio
Hausner ratio is an indirect index of ease of powder flow. It is calculated by the following
formula.
Hausner ratio = ρt / ρb
Where ρt= Tapped density
ρb= Bulk density
Lower Hausner ratio (< 1.25) indicates better flow properties than higher ones (> 1.25).
So, in the above mentioned manner, all the drug free blends were evaluated. The
characterization of blends is an important aspect and gives an idea of the characteristics of final
preparation. This is because the flow properties affect the flow of powder from the hopper into
die during the process of punching. Compressibility affects the hardness, size of the tablet and
further its disintegration and release
Table 7.7:Precompression parameters of the blends
Formulation Bulk
Density
ρb= M / Vb
( g/cm3
)
Tapped
Density
ρt= M / Vt
Angle of
Repose
θ = Tan-1
h /
r
Compressibility
Index
I = (ρt –ρb) / ρt
×100
Hausner’s ratio
Hausner ratio =
ρt / ρb
F1 0.62 0.74 32.45 16 1.19
F2 0.57 0.7 24.54 19 1.23
F3 0.58 0.69 25.70 16 1.19
F4 0.59 0.69 28.21 16 1.17
F5 0.59 0.67 28.32 12 1.14
F6 0.59 0.67 27.41 12 1.14
F7 0.6 0.69 26.35 13 1.15
F8 0.54 0.64 25.65 16 1.19
F9 0.53 0.62 25.32 15 1.17
F10 0.53 0.62 25.28 15 1.19
F11 0.55 0.64 24.54 14 1.16
F12 0.56 0.69 25.70 19 1.23
F13 0.59 0.69 26.47 14 1.17
F14 0.57 0.66 28.56 14 1.16
F15 0.59 0.66 27.41 11 1.12
F16 0.61 0.68 26.35 10 1.19
F17 0.52 0.64 24.56 19 1.23
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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F18 0.53 0.62 25.32 15 1.19
F19 0.53 0.63 25.78 16 1.17
F20 0.62 0.78 29.47 21 1.26
F21 0.54 0.65 25.44 17 1.20
F22 0.59 0.68 25.69 13 1.15
F23 0.6 0.69 27.22 13 1.15
F24 0.58 0.67 28.31 13 1.16
F25 0.58 0.67 27.40 13 1.16
F26 0.61 0.69 26.35 12 1.13
F27 0.52 0.59 26.64 12 1.13
F28 0.53 0.6 24.31 12 1.13
F29 0.51 0.6 24.27 15 1.18
F30 0.54 0.67 25.29 19 1.24
F31 0.58 0.65 24.15 14 1.16
F32 0.59 0.60 26.54 16 1.19
F33 0.61 0.73 25.48 16 1.20
F34 0.58 0.69 24.04 16 1.19
F35 0.57 0.65 25.32 12 1.14
F36 0.62 0.62 24.54 19 1.24
F37 0.60 0.60 25.61 11 1.12
F38 0.58 0.69 26.58 16 1.15
ρb= Bulk densityρt= Tapped density M = Mass of sample in g Vb= Bulk volume of blend in cm3
θ = angle of repose h = height of cone r = radius of cone
7.1.3 METHOD OF PREPARATION OF FAST DISSOLVING TABLETS2,3
Direct compression of the blends was carried out on single punch Cadmach (OMS – 15) tablet
press, using 8mm punch.
7.1.4EVALUATION OF FAST DISSOLVING TABLETS1,3,4,5
After compression of blends, the tablets were evaluated for physical characteristics like odor,
color, shape, diameter, thickness, hardness, wetting time, disintegration time.
7.1.4.1 Thickness
Tablet thickness is an important characteristic in reproducing appearance and also in counting
by suing filling equipment. Some filling equipment utilizes the uniform thickness of the tablets
as a counting mechanism. Micrometer or Vernier Calipers were used to measure the thickness
of the tablet as done in case of conventional tablets. Ten tablets were randomly selected to
perform the process.
7.1.4.2 Weight uniformity
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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The standard pharmacopoeial procedures were followed for this purpose. According to USP,
20 tablets were randomly selected and individually as well as collectively weighed on a digital
balance. The average weight was calculated. The weight variation test would be satisfactory
method of determining the drug content uniformity (table 7.8)
Table 7.8: Weight Variation Allowance
Average Weight of Tablets (mg) Maximum % age Difference Allowed
130 or less 10
130-324 7.5
More than 324 5.0
7.1.4.3 Tablet hardness
It can be defined as the force required per unit area to break the tablet. The resistance of the
tablet to chipping, abrasion or breakage under condition of storage transformation and handling
before usage depends on its hardness. Hardness can be expressed in terms of kg/sqcm. For a
fast dissolving tablet, the hardness should be 1-3 kg/cm2. Hardness of the tablets was
determined by using Monsanto hardness tester.
7.1.4.4 Wetting time
Wetting time is closely related to the inner structure of the tablets and to the hydrophilicity of
the excipient. The water penetration rate into the powder bed is proportional to the pore radius
and is affected by thehydrophilicity of the powders according to the following equation.
dl/dt = γ cos θ r / (4ηl)
Where l = the length of penetration, r =capillary radius, γ = surface tension,
η = liquid viscosity, t = time
θ is the contact angle. It is obvious that pore size becomes smaller and wetting time increases
with an increase in compression force or a decrease in porosity. A linear relationship exists
between wetting time and disintegration time. Thus wetting is the important step for
disintegration process to take place. A double folded piece of tissue paper was placed in a petri
plate (internal diameter is 6.5 cm) containing 6ml of water. The tablet was placed on the paper
and the time for complete wetting of the tablet was measured in seconds. The method was
slightly modified by maintaining water at 37°C wetting time corresponds to the time taken for
the tablet to disintegrate when kept motionless on the tongue.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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7.1.4.5 Disintegration time
Disintegration time for mouth dissolving tablets can be measured by using conventional tests
for tablets, described in pharmacopoeia. But the conventional tests use a volume of 900 ml of
test solution, as compared to the volume of saliva, which is less than 1 ml. Thus the
disintegration rate does not appear to reflect the actual disintegration rate in human mouth. So,
an alternative method was followed. A tablet was dropped in a beaker containing 50 ml of pH
6.8 buffer. Tablets from each batch were randomly selected and in vitro disintegration time
was determined.
7.1.4.6 Drug content
10 tablets were randomly selected and weighed. Average weight was calculated. Tablets were
powdered in a glass mortar. Powder equivalent to 30 mg was weighed and dissolved in 30 ml
of methanol to obtain a stock solution of 1000 μg/ml. 1 ml was pipetted out and diluted with
methanol to 10 ml in each case, so as to get 100 μg/ml solutions. The absorbance was noted
down after filtering off the solutions at 227 nm and 284 nm for gliclazide and domperidone
respectively. The amount of drug present in each tablet was calculated and compared with the
claimed amount. The observation were recorder in table 7.9
Table 7.9: Evaluation of tablets
Form
ulatio
n
Thickness
(mm) (n=10)
Weight
(mg) (n=20)
Friability
(%)
(n=20)
Hardness
(kg/cm2)
(n=5)
Wetting
Time (s)
(n=5)
Disintegrat
ion Time
(s) (n=5)
%
Uniformity
of content
(n=10)
F1 4.58±0.08 219.25±2.57 0.402±0.50 3.5 ±0.42 102.5±0.9 192.2±1.3 98.54±0.52
F2 4.55±0.09 218.02±2.58 0.207±0.09 2.6±0.48 45.2±1.0 47.1±2.4 97.75±1.54
F3 4.58±0.06 218.25±2.54 0.266±0.50 2.6 ±0.42 39.5±0.9 44.2±1.3 98.68±0.52
F4 4.45±0.01 220.32±1.51 0.245±0.07 2.5±0.32 40.5±0.1 41.9±1.5 98.54±0.52
F5 4.53±0.05 220.54±1.38 0.304±0.01 2.4±0.26 42.8±0.4 44.9±1.5 99.32±0.34
F6 4.55±0.07 219.20±1.31 0.316±0.12 2.5±0.31 39.8±0.4 40.3±1.0 98.68±0.52
F7 4.52±0.04 218.02±2.58 0.305±0.13 2.6±0.28 42.6±0.5 32.6±1.3 99.27±0.28
F8 4.46±0.02 221.14±2.03 0.316±0.12 2.5±0.34 31.4±1.6 33.7±0.4 98.23±0.64
F9 4.57±0.04 219.20±1.31 0.353±0.04 2.6±0.25 27.2±1.0 27.5±0.5 99.05±0.56
F10 4.52±0.04 219.20±1.54 0.365±0.08 2.7±0.27 22.5±0.9 24.9±2.4 99.87±0.82
F11 4.57±0.08 228.02±2.48 0.210±0.10 2.5±0.48 48.2±1.0 48.1±2.4 98.68±0.52
F12 4.52±0.06 218.25±1.51 0.267±0.03 2.5 ±0.42 40.5±0.9 44.2±1.3 99.27±0.28
F13 4.75±0.01 220.32±2.51 0.248±0.07 2.6±0.32 42.5±0.1 42.9±1.5 98.23±0.64
F14 4.53±0.05 228.54±1.38 0.303±0.01 2.3±0.26 43.8±0.4 45.9±1.5 99.05±0.56
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
School of Pharmaceutical Sciences Shobhit University Meerut 128
F15 4.53±0.07 219.20±1.31 0.317±0.12 2.5±0.31 40.8±0.4 35.3±1.0 99.87±0.82
F16 4.42±0.04 217.02±2.28 0.302±0.13 2.6±0.28 47.6±0.5 32.6±1.3 97.75±1.54
F17 4.48±0.02 225.14±2.14 0.317±0.11 2.5±0.34 32.4±1.6 38.7±0.4 98.68±0.52
F18 4.54±0.04 214.20±1.89 0.354±0.04 2.7±0.25 28.2±1.0 29.5±0.5 98.54±0.52
F19 4.57±0.04 218.20±1.84 0.465±0.08 2.6±0.27 22.5±0.9 25.9±2.4 99.32±0.34
F20 4.68±0.09 218.25±2.57 0.412±0.50 3.8 ±0.42 118.2±0.9 198.9±1.3 98.27±0.42
F21 4.55±0.09 218.02±2.58 0.207±0.09 2.6±0.48 45.2±1.0 47.1±2.4 97.75±1.54
F22 4.58±0.06 218.25±2.54 0.266±0.50 2.6 ±0.42 39.5±0.9 44.2±1.3 98.68±0.52
F23 4.45±0.01 220.32±1.51 0.245±0.07 2.5±0.32 40.5±0.1 41.9±1.5 98.54±0.52
F24 4.53±0.05 220.54±1.38 0.304±0.01 2.4±0.26 42.8±0.4 44.9±1.5 99.32±0.34
F25 4.55±0.07 219.20±1.31 0.316±0.12 2.5±0.31 39.8±0.4 36.3±1.0 98.68±0.52
F26 4.52±0.04 218.02±2.58 0.305±0.13 2.6±0.28 42.6±0.5 32.6±1.3 99.27±0.28
F27 4.46±0.02 221.14±2.03 0.316±0.12 2.5±0.34 31.4±1.6 33.7±0.4 98.23±0.64
F28 4.57±0.04 219.20±1.31 0.353±0.04 2.6±0.25 27.2±1.0 27.5±0.5 99.05±0.56
F29 4.52±0.04 219.20±1.54 0.365±0.08 2.7±0.27 22.5±0.9 24.9±2.4 99.87±0.82
F30 4.57±0.08 228.02±2.48 0.210±0.10 2.5±0.48 48.2±1.0 48.1±2.4 98.68±0.52
F31 4.52±0.06 218.25±1.51 0.267±0.03 2.5 ±0.42 40.5±0.9 44.2±1.3 99.27±0.28
F32 4.75±0.01 220.32±2.51 0.248±0.07 2.6±0.32 42.5±0.1 42.9±1.5 98.23±0.64
F33 4.53±0.05 228.54±1.38 0.303±0.01 2.3±0.26 43.8±0.4 45.9±1.5 99.05±0.56
F34 4.53±0.07 219.20±1.31 0.317±0.12 2.5±0.31 40.8±0.4 35.3±1.0 99.87±0.82
F35 4.42±0.04 217.02±2.28 0.302±0.13 2.6±0.28 47.6±0.5 32.6±1.3 97.75±1.54
F36 4.48±0.02 225.14±2.14 0.317±0.11 2.5±0.34 32.4±1.6 38.7±0.4 98.68±0.52
F37 4.54±0.04 214.20±1.89 0.354±0.04 2.7±0.25 28.2±1.0 29.5±0.5 98.54±0.52
F38 4.57±0.04 218.20±1.84 0.465±0.08 2.6±0.27 22.5±0.9 25.9±2.4 99.32±0.34
7.4.1.7 In vitro dissolution studies
In vitro dissolution studies for all formulations was carried out using USP paddle method at 50
rpm in 900 ml of phosphate buffer pH 6.8 as dissolution media, maintained at 37±0.5oC. Five
ml aliquots were withdrawn at the specified time intervals, filtered through whatmann filter
paper and assayed spectrophotometrically at 227 nm and 284 nm for gliclazide and
domperidone respectively. An equal volume of fresh medium, which was pre-warmed at 37oC
was replaced into the dissolution media after each sampling to maintain the constant volume
throughout the test. The dissolution data is given in tables 7.10 – 7.13 and figures 7.1 – 7.4.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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7.2 STABILITY STUDIES
Stability studies of the developed formulations were carried out according to ICH and WHO
guidelines. The formulations F10, F19, F29, and F38 sealed in aluminum foils were kept in the
stability chamber (LABINDIA) maintained at 400 C ± 2
0C and 75 % ± 5% RH for 3 months.
The samples were analyzed for the appearance, weight, hardness, wetting time, disintegration
time, drug content and drug release at three time intervals “i.e.” 1 month, 2 months and 3
months (Edward 2005).Stability data is presented in table 11. None of the samples showed any
change in color or appearance under all storage conditions for 3 months. The drug content of
the formulation was estimated initially and then after 1 month interval up to three months using
double beam UV-visible spectrophotometer Shimadzu 1700.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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7.3 RESULTS AND DISCUSSION
Several technologies are available to manufacture orally disintegrating tablets. The
most common preparation methods include molding, lyophilization or freeze drying, direct
compression, spray drying and sublimation. In the present investigation fast dissolving tablets
of gliclazide and domperidone solid dispersions were prepared by direct compression method.
Flow properties of the powder, resistance to particle movement can be judged from the angle
of repose. This measurement gives qualitative and quantitative assessment of internal cohesive
and frictional force under low levels of external loading as might be applied in mixing and
tableting.
The solid dispersions of gliclazide and domperidone were mixed with appropriate
quantities of excipients to make the blends for fast dissolving tablets. The blends were
evaluated for bulk density, tapped density, angle of repose, compressibility index and Hausner
ratio.
Values for angle of repose for gliclazide blends were found in the range of 24.54°-
32.45° and that of domperidone blends were found to be 24.04°-29.47°. Compressibility index
of the blends fell in the range of 10-19 for gliclazide and in the range of 11-21 for domperidone
which complied with the to Hausner ratio values which were in the range of 1.14-1.23 for
gliclazide and 1.13-1.26 for domperidone. The prepared blends were found to possess good
flow and compressibility properties and thus were suitable for tablet manufacture.
The tablets were prepared using direct compression method on single punch Cadmach
tablet press using 8mm punches. The fast dissolving tablets were evaluated for various
parameters including thickness, weight uniformity, hardness, wetting time, in vitro
disintegration time, drug content and in vitro dissolution.
Uniformity of weight of the FDTs was assessed and the average weight for all
formulations was found to be between 214-228 mg which was within in the prescribed limits
i.e. ±7.5% (203.5 to 236.5mg).
Hardness and friability of all formulations were within acceptable limits. Hardness of
tablets was in the range of 2.3-3.5 kg/cm for gliclazide tablets and 2.3-3.8 kg/cm for
domperidone tablets. The friability of all formulations was found to be less than 1.0 % and
hence the tablets exhibited sufficient strength against bear and tear during handling and
shipping. Friability was found to be in the range of 0.207- 0.402% for gliclazide tablets and as
well as for domperidone tablets.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
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Disintegration time is very important for FDTs which is desired to be less than 60
seconds. This rapid disintegration assists swallowing and also plays a role in drug absorption in
buccal cavity, thus promoting bioavailability. Disintegration time of prepared FDTs was in the
range of 25-47 seconds for gliclazide tablets and 26-48 sec for domperidone tablets. The
disintegration time was found to be increased in the following order; Kyron<Crosscarmellose<
SSG. This finding is in agreement with results obtained from wetting time, since SSG swells
with more gelling than Crosscarmellose and Kyron, which extend disintegration time as a
result. As the concentration of superdisintegrants in the formulations was increased the
disintegration time was found to decrease.
Wetting time is used as an indicator for the ease of the tablet disintegration in buccal
cavity. It was observed that wetting time of tablets was in the range of 23-48 seconds for all
the tablets. It was observed that type of the disintegrant affected the wetting of the tablets. It
was noted that the formulation containing SSG took more time to wet than the tablet
containing Croscarmellose and Kyron. Wetting is related to the inner structure of the tablets
and hydrophobicity of the components. This may be due to the fact that SSG is disintegrated
by swelling mechanism leading to longer wetting time while Crosscarmellose and Kyron
perform their disintegrating action by wicking through capillary action and fibrous structure,
with minimum gelling. The relative ability of the various disintegrants to wick water into the
tablets was studied. After contact with water the tablets containing SSG swelled and the outer
edge appeared gel-like. Tablets containing Kyron quickly wicked water and were hydrated, but
were soft as compared to the tablets prepared with Crosscarmellose and SSG. It was further
noted that the centers of the tablets with Crosscarmellose and SSG remained dry and hard.
The drug content of the gliclazide tablets was in the range of 98-100% while for
domperidone tablets it was in the range of 98-99%. On the basis of better dissolution and other
favourable parameters the formulation F10 i.e., tablet containing solid dispersion of gliclazide
and PEG 8000 with 8 mg Kyron, formulation F19 i.e., tablet containing solid dispersion of
gliclazide and PVP K90 with 8 mg Kyron, formulation F29 i.e., tablet containing solid
dispersion of domperidone and PEG 8000 with 8 mg Kyron and formulation F38 i.e., tablet
containing solid dispersion of domperidone and PVP K90 with 8 mg Kyron were selected for
the stability studies.
Stability studies were performed as per ICH guidelines at 40°C and 75% RH. The
selected formulation exhibited satisfactory stability. In the present study it can be concluded
from the characterization of fast dissolving tablets that formulation containing Kyron is most
acceptable. These formulations were also found to be stable.
Chapter 7 Formulation and Evaluation of Fast Dissolving Tablets
School of Pharmaceutical Sciences Shobhit University Meerut 139
7.4 REFERENCES
1. Marshall K, Lachmann Liberman HA, Kanig JL. The theory and practice of industrial
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2. Martin A. Physical Pharmacy .2nd
edition. B I Waverly Pvt. Ltd. 1993; 212.
3. Libermann HA, Lachmann L. In pharmaceutical dosage forms: tablets. Volume 2.
Marcell Decker. Inc. New York. 1991; 209-215.
4. Dor JMP, Fix JA. In vitro determination of disintegration time of quick
dissolve tablets using a new method. Pharm Dev Tech. 2000; 5(4):575-577.
5. Nadendla RR, Sudhakar G, Srinath N. Mouth dissolving tablets and their evaluation.
Int J Pharma Excp. 2002; 1:25.
6. ICH Topic Q 1 A (R2) Stability testing of new drug substances and products.
European medicines agency. 2003; CPMP/ICH/2736/99.7.