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Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
49
International Journal of Farmacia
Journal Home page: www.ijfjournal.com
Formulation and in vitro evaluation of fast melting tablets of Fexofenadine
*Yasmeen, Pamu Sandhya
Shadan Women’s College of Pharmacy, Khairatabad, Hyderabad, Telangana 500004
*Corresponding author: Yasmeen
*Email: yasmeen_mpharm016@yahoo.com
Abstract
Fexofenadine Hydrochloride is an antihistamine drug used in the treatment of hay fever and similar allergy
symptoms. It does not readily pass through the blood-brain barrier and causes less drowsiness than first generation
histamine-receptor antagonists. Fourteen batches of rapid dispersible tablets of Fexofenadine Hydrochloride were
prepared using Cross Povidone, Cross carmellose Sodium and Sodium Starch Glycolate as Superdisintegrants in
different concentrations and in different combinations by Direct Compression method. Preformulation studies of
Fexofenadine Hydrochloride were performed, from the FT-IR; the interference was verified and found that
Fexofenadine Hydrochloride did not interfere with the polymers used. Fexofenadine Hydrochloride formulated as
Rapid Dispersible Tablets gives best results. Also negligible side effects makes it superior and effective candidate
for pediatric, geriatric, bedridden and psychotic patients.
Keywords: Fexofenadine hydrochloride, Super-disintegrants, Formulation and Evaluation.
INTRODUCTION
Many pharmaceutical dosages are administered in
the form of pills, granules, powders, and liquids.
Generally, a pill design is for swallowing intact or
chewing to deliver a precise dosage of medication to
patients. The pills, which include tablets and capsules,
are able to retain their shapes under moderate pressure
[1]. However, some patients, particularly pediatric and
geriatric patients, have difficulty swallowing or
chewing solid dosage forms. Many pediatric and
geriatric patients are unwilling to take these solid
preparations due to fear of choking. Hence orally
dissolving tablets have come into existence [2, 3].
To fulfill these medical needs, formulators have
devoted considerable efforts for developing a novel
type of dosage form for oral administration known as
Rapid Dispersible Tablets (RDT). This is an
innovative technology where the dosage form
containing active pharmaceutical ingredients
disintegrates rapidly, usually in a matter of seconds,
without the need for water, providing optimal
convenience to the patient. Fexofenadine is a second-
generation, long lasting H1-receptor antagonist
(antihistamine) which has a selective and peripheral
H1-antagonist action. Fexofenadine Hydrochloride is a
white to off-white crystalline powder. Dose is 30mg.
Its chemical name is 4-[1-hydroxy-4-
[4(hydroxydiphenylmethyl)-1 piperidinyl] butyl]-
(alpha). Its Molecular weight is 538.13 and Emperical
formula is C32H39NO4 .HCL. Freely soluble in
methanol and ethanol, slightly soluble in chloroform
and water, insoluble in hexane. Bioavailability and
Protein binding are 30-41% and 60-70% respectively.
Half-life is 14.4hours. 80% Excretion is through feces.
Unlike most other antihistamines, it does not enter the
brain from the blood and therefore, does not cause
drowsiness. Fexofenadine lacks the cardiotoxic
potential of terfenadine, since it does not block the
potassium channel involved in repolarization of
cardiac cells [4].
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
50
MATERIALS AND METHODS
All the chemicals obtained and used are of
analytical grade. Fexofenadine Hydrochloride,
Magnesium stearate, Talc, Microcrystalline Cellulose,
Cross Povidone, Sodium Starch Glycolate, Cross
Carmellose Sodium, Aerosil, Mannitol, Hydroxyl
propyl methyl cellulose E15 LV and Hydroxyl propyl
methyl cellulose 5cps were obtained from Baris
Pharmaceuticals, Hyderabad and Bright
Pharmaceuticals [5].
Methods
Preparation of Oral disintegrating tablets
In the present study, the oral disintegrating tablets of
Fexofenadine Hydrochloride are prepared by Direct
compression method, using different polymer and
concentrations.
Preparation of tablets by the direct
compression technique
The steps followed in the formulation of ODT’s by
direct compression technique includes: Dry screening,
weighing, mixing, mixing of Super Disintegrants,
lubricant and glidant then compressing [6].
Procedure
All the required ingredients were passed through
40 mesh size to get uniform size particles and weighed
accurately. Measured amount of drug,
superdisintegrants, Avicel, sweetner and flavor except
glidant and lubricant are mixed in increasing order of
their weights in a mortar. To this mixture talc and
magnesium stearate were added. The final mixture is
manually shaken for 10mins in plastic bag. Final blend
was compressed into tablets using 8mm s/c round, flat
punches using Karnavathi, Rimek Compression Tablet
Punching Machine [7].
Development of the formulation in the present
study was mainly based on the type and concentration
of polymers and properties of the drug. Various
polymers in different concentrations were used so as to
get tablets with good physical properties.
In the following formulations cross povidone,
sodium starch glycolate and cross carmellose sodium
were used in 4%, 8% and 12% concentrations each
then another set of formulations were done using
combinations of two superdisintegrants in different
concentrations [8].
Table 1: Formulation design of Fexofenadine Hydrochloride Rapid dispersible tablets
Ingredients T1 T2 T3 T4 T5 T6 T7 T8 T9
Fexofenadine Hyrochloride 30 30 30 30 30 30 30 30 30
Cross povidone 8 16 24 - - - - - -
Sodium starch glycolate - - - 8 16 24
Cross carmellose sodium - - - - - - 8 16 24
Magnesium stearate 2 2 2 2 2 2 2 2 2
Aerosil 2 2 2 2 2 2 2 2 2
Microcrystalline cellulose 155 147 139 154 146 138 153 145 137
Talc 2 2 2 2 2 2 2 2 2
Mannitol 1 1 1 2 2 2 3 3 3
Evaluation
Weight variation test
Method
20 tablets were randomly selected from each
formulation and their average weight was calculated
using digital balance (Denver, Germany). Then
individual tablets were weighed and the individual
weight was compared with an average weight, the
variation in the tablet was expressed in terms of
%deviation.
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
51
Table 2: Limits of weight variation
Average weight of tablet % Weight variation
130mg or less 10
More than 130mg, less than 324mg 7.5
More than 324mg 5
Thickness measurement
Method
Randomly 10 tablets were taken from each
formulation and their thickness was measured using a
digital screw guage, (Digimatic outside micrometer,
Mitutoyo, Japan). The individual tablet was paced
between two anvils of screw guage and sliding knob
was rotated until the tablet was tightly fitted. The
digital reading displayed was noted [9].
Hardness and Friability
Method (Hardness)
The tablet hardness of different formulations was
measured using a Monsanto hardness tester. The tester
consists of a barrel containing a compressible spring
held between two plungers. The lower plunger was
placed in contact with the tablet and a zero was taken
[10].
The upper plunger was then forced against the
spring by turning a threaded bolt until the tablet
fractures. As the spring is compressed, a pointer rides
along a guage in the barrel to indicate the force. The
force of fracture is recorded, and the zero force
reading is deducted from it. Generally, a minimum
hardness of 4 kg is considered acceptable for uncoated
tablets. The hardness for ODTs should be preferably
1-3 kg.
Method (friability)
This test is performed using a laboratory friability
tester known as Roche Friabilator. 10 tablets were
weighed and placed in a plastic chambered friabilator
attached to a motor, which revolves at a speed of 25
rpm, dropping the tablets from a distance of 6 inches
with each revolution. The tablets were subjected to
100 revolutions for 4 mins. After the process, these
tablets were dedusted and reweighed. Percentage loss
of tablet weight was calculated [11].
Drug content uniformity
Five tablets were weighed individually and
powdered. The powder equivalent to 30mg of
fexofenadine hydrochloride was weighed and
extracted in phosphate buffer 6.8pH and the
concentration of drug was determined by measuring
absorbance at 224nm by UV-Visible
spectrophotometer [12].
Wetting time and water absorption ratio (R)
Method
Five circular tissue papers were placed in a Petri
dish with a 10-cm diameter. Ten millimeters of water
containing Eosin, a water-soluble dye, was added to
the Petri dish. The dye solution is used to identify the
complete wetting of the tablet surface. A tablet was
carefully placed on the surface of tissue paper in the
Petri dish at room temperature. The time required for
water to reach the upper surface of the tablets and
completely wet them was noted as the wetting time.
To check for reproducibility, the measurements were
carried out in replicated (n=6). The wetting time was
recorded using a stopwatch [13].
The weight of the tablet before keeping in the Petri
dish was noted (Wь) using Shimadzu digital balance.
The wetted tablet from the Petri dish was taken and
reweighed (Wa) using the same. The water absorption
ratio, R, was determined according to the following
equation:
R = 100 (Wa – Wb) / Wb
Where,
Wb and Wa are the weight before and after water
absorption respectively.
Disintegration Time
Disintegration time is considered to be one of the
important criteria in selecting the best formulation. To
achieve correlation between disintegration time In
vitro and In vivo (in oral cavity) several methods were
proposed, developed and followed at their
convenience. One of the simple methods followed is
described below [14].
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
52
Method
Disintegration time was also measured using a
modified disintegration method. For this purpose, a
Petri dish (10 cm diameter) was filled with 10ml of
water.
Tablet was carefully put in the centre of the Petri dish
and the time for the tablet to completely disintegrate
into find particles was moved using a pump watch
[15].
Dissolution test
Method
Drug release from RDTs was studied by using USP
type-II dissolution rate test apparatus at 50rpm (USP
XXIII Dissolution Test Apparatus) using 900ml of
phosphate buffer pH6.8 as dissolution medium. RDTs
of desired formulation were taken and placed in the
vessels of dissolution apparatus. Samples were
collected from the vessels at different time intervals,
replenished with same volume of the blank solution
and analyzed using UV-Visible spectrophotometer.
Drug concentration was calculated from the standard
graph and expressed as % of drug dissolved or
released. The release studies were performed in
replicates and means values were taken [16].
Table 3: Details of in vitro drug release study
Apparatus used USP XXIII dissolution test apparatus
Dissolution Medium 6.8 pH Phosphate buffer
Dissolution Medium Volume 900ml
Temperature 37±0.5ºC
Speed Of Paddle 50rpm
Time Intervals 2,5,10,15,30,45,60mins
Sample Withdrawn 5ml
Absorbance Maximum λmax 224nm
Stability Studies
Stability of a drug is defined as the ability of a
particular formulation, in a specific container, to
maintain its physical, chemical, therapeutic and
toxicological specifications.
The purpose of stability testing is to provide
evidence on how the quality of a drug substance varies
with time under the influence of variety of
environmental conditions and enables recommended
storage conditions, re-test periods and shelf lives to be
established.
RESULTS AND DISCUSSIONS
Preformulation studies
Determination of solubility
It was observed that it is sparingly soluble in water
and chloroform, completely soluble in ethanol and
methanol and insoluble in hexane.
Determination of drug polymer compatibility
studies using FTIR
Drug excipient interactions play a crucial role with
respect to the stability and potency of the drug. FTIR
techniques have been used to study the physical and
chemical interaction between the drug and excipients
used.
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
53
Fig 1: FT-IR spectra of Fexofenadine Hydrochloride
Fig 2: FT-IR spectra of Cross carmellose Sodium
3292.483 284.976
2639.115 42.856
2084.592 1.151
1701.194 360.906
1401.248 75.752
1335.026 82.301
1277.952 182.482
1160.319 309.745
1067.963 80.747
983.601 58.165
964.925 96.991
832.457 103.714
744.582 190.934
695.342 -1.299
638.879 44.890
574.478 105.534
DrugFexofenadineHCL
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
90
80
70
60
50
Wavenumber
%Transmittance
3390.115 4.236
2122.469 6.567
1586.724 69.285
1412.183 17.565
1320.255 115.206
1254.549 11.177
1104.627 493.440
1049.177 41.707
894.740 60.202
662.196 -0.002
614.115 46.633
418.859 46.556
405.532 2.395
CCS
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
100
90
80
70
60
50
40
Wavenumber
%Transmittance
3274.368 1.188
2928.641 593.025
2086.931 16.339
1590.225 425.817
1322.721 253.482
1149.249 268.090
1076.700 96.910
996.157 1672.481
859.999 146.977
762.002 71.834
703.402 72.837
571.949 112.201
SSG
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
100
90
80
70
60
50
40
30
20
Wavenumber
%Transmittance
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
54
Fig 3: FT-IR spectra of Sodium Starch Glycolat
Fig 4: FT-IR spectra of HPMC K 15
Fig 5: FT-IR spectra of optimized RDTof Fexofenadine Hydrochloride
Fig 6: FT-IR spectra of optimized RDF of Fexofenadine Hydrochloride
2897.562 307.285
1374.508 -0.001
1313.619 40.954
1187.481 54.237
1050.195 3476.235
942.943 521.285
653.641 34.416
564.886 23.846
HPMCE15
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
100
80
60
40
Wavenumber
%Transmittance
3292.953 159.029
1702.149 -0.005
1429.769 52.084
1314.534 81.456
1246.816 34.939
1203.381 58.816
1160.538 281.653
1103.854 263.988
1053.657 160.846
1029.727 83.617
662.628 69.484
608.540 27.901
557.150 87.664
518.482 45.067
434.055 44.642
OptimisedODT
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
100
90
80
70
60
50
40
30
Wavenumber
%Transmittance
3248.469 0.907
2944.826 106.590
1330.894 7.541
1211.353 46.904
1110.593 177.038
1039.875 730.080
993.518 131.060
843.752 52.171
551.817 4.627
OPTIMISEDFILM
3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800
100
80
60
40
Wavenumber
%Transmittance
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
55
Determination of absorption maximum λmax
In the preformulation study, it was found that the
λmax of Fexofenadine hydrochloride by
spectrophotometric method in 6.8pH phosphate buffer
was found to be 224nm.
Fig 7: λmax of Fexofenadine Hydrochodride in 6.8pH phosphate buffer
Pre-compression parameters
Table 4: Evaluation of the flow properties of powder blend for formulations T-1 to T-9
Post compression studies
Table 5: Evaluation of tablets for weight variation, thickness, hardness and friability
S.
No
Formulations *Weight variation
(mg)
*Thickness
(mm)
*Hardness
(kg/cm2
)
Friability
(%)
1 T1 199.10±0.20 2.38±0.03 2.56±0.13 0.45
2 T2 201.09±0.33 2.47±0.01 2.52±0.11 0.53
3 T3 198.80±0.34 2.5±0.02 3.46±0.25 0.49
4 T4 200.33±0.76 2.46±0.04 3.32±0.21 0.57
5 T5 200.34±0.48 2.38±0.12 2.91±0.15 0.68
6 T6 201.67±0.27 2.5±0.02 2.96±0.17 0.62
7 T7 200.43±0.71 2.33±0.14 3.46±0.25 0.51
8 T8 200.19±0.21 2.5±0.02 3.05±0.21 0.63
9 T9 199.26±0.20 2.4±0.02 3.04±0.21 0.65
*Values expressed as mean±SD, n=3
S.
No
Formulations Angle of
repose (θ)
Bulk density
(gm/cc)
Tapped density
(gm/cc)
Carr’s index
(%)
Hausner’s
ratio
1 T1 21.43 0.65 0.72 10.22 1.11
2 T2 20.55 0.69 0.79 12.65 1.14
3 T3 21.45 0.69 0.81 14.81 1.17
4 T4 20.67 0.70 0.82 14.63 1.17
5 T5 20.84 0.64 0.72 11.11 1.12
6 T6 20.82 0.64 0.73 12.32 1.14
7 T7 22.29 0.65 0.74 12.16 1.13
8 T8 22.32 0.71 0.83 14.45 1.16
9 T9 21.27 0.70 0.80 12.50 1.14
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
56
Table 6: Evaluation of the disintegration time, wetting time and water absorption ratios
S. No Formulations Disintegration time (sec) Wetting time (sec) Water absorption ratio
1 T1 22 20 109
2 T2 20 18 100
3 T3 18 16 96
4 T4 38 36 97
5 T5 26 23 87
6 T6 19 22 107
7 T7 60 57 108
8 T8 55 50 99
9 T9 30 25 95
Table 7: Percentage Cumulative drug release of tablets in 6.8pH phosphate buffer
Time (min) T1 T2 T3 T4 T5 T6 T7 T8 T9
2 30.67 43.65 50.36 33.12 68.85 56.3 64.05 69.02 70.15
5 39.15 58.05 64.2 46.24 87.75 61.4 71.95 73.15 82.05
10 50.9 76.95 76.11 66.1 90.1 84.65 74.4 86.75 86.6
15 67.06 87.15 83.49 74.94 99.2 89.7 87.95 91.85 90.2
30 84.23 91.5 100.01 96.8 98.57 98.1 96.45 96.6 96
45 91.35 97.65 101.55 102.4 102.15 101.3 101 101.15 102.35
60 98.84 101.3 104.2 - - - - 105.2 -
Fig 8: Cumulative percentage drug release of T1-T3 with Cross Povidone
0
20
40
60
80
100
120
0 2 5 10 15 30 45 60
%cumulativedrugrelaese
Time (min)
% Drug Release of T1-T3
T1
T2
T3
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
57
Fig 9: Cumulative percentage drug release of T4-T6 with Sodium Starch Glycolate
Fig 10: Cumulative percentage drug release of T7-T9 with Cross Carmellose Sodium
Comparison with marketed product
Brand Name: Allegra
Table 8: Comparison of Percentage Cumulative drug release of Optimized formulation (F13) of Fexofenadine
Hydrochloride and the marketed tablet
Time (min) % Cumulative Drug Release
T13 Marketed Tablet
2 99.63 69.3
5 99.82 76.95
10 99.91 82.55
15 100.62 94.69
30 101.83 99.99
45 102.94 100.26
60 103.56 101.49
0
20
40
60
80
100
120
0 2 5 10 15 30 45 60
%cumulativedrugrelease
Time (min)
% Drug Release of T4-T6
T4
T5
T6
0
20
40
60
80
100
120
0 2 5 10 15 30 45 60
%cumulativedrugrelease
Time (min)
% Drug Release of T7-T9
T7
T8
T9
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
58
Fig 11: Comparison of percentage drug release between optimized and marketed formulation
Accelerated Stability Studies
Table 9: Accelerated Stability Study data of Optimized Formulation
Stability Period % Drug Content % In vitro Release
Initial 98±0.05 100±0.01
30 Days 97±0.86 99±0.24
60 Days 97±0.64 99±0.18
90 Days 97±0.02 99±0.05
*Values expressed as mean±SD, n=3
Oral disintegrating drug delivery system have an
advantage over the conventional drug delivery system
in pediatric, elderly, bed ridden, mentally retarted and
patients suffering with dysphagia. As these kind of
patients need special attention and monitoring, in the
present study an attempt has been made to formulate
and evaluate Rapid Dispersible tablets and films of
Fexofenadine Hydrochloride by Direct Compression
method using different superdisintegrants in different
concentrations.
Solubility, Determination of of λ max ,
Construction of calibration curve, Drug
polymer compatibility studies
The solubility of Fexofenadine Hydrochloride
reveals that it is sparingly soluble in water and
chloroform, completely soluble in ethanol and
methanol and insoluble in hexane.
In the Preformulation studies, the lambda max of
Fexofenadine Hydrochloride was determined by
Spectroscopic Method and it was found to be 224nm
with 6.8pH phosphate buffer.
In this study at 224nm in 6.8pH phosphate buffer
had good reproducibility in the concentration between
10-50µg/ml. Correlation between concentration and
absorbance was found to be closer to 1 indicating that
the method obeyed Beer-Lambert’s Law.
Fourier-Transformed Infrared (FTIR)
Spectrophotometer technique has been used to study
the physical and chemical interaction between the drug
and excipients used.
0
20
40
60
80
100
120
0 2 5 10 15 20 45 60
%cumulativedrugrelease
Time (min)
% Drug release of T3 and Marketed tablet
T13
ALLEGRA
Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60
59
Table 10: FT-IR data interpretation
The FT-IR spectrum of pure drug and different
excipients and the optimized tablet and film
formulation were studied. There was no significant
difference between the absorption peaks of pure drug
and optimized formulation. The results concluded that
there was no interaction between pure drug and
excipients.
Angle of repose, Bulk density, Tapped density,
Carr’s compressibility index and Hausner’s
Ratio
The angle of repose for the formulation blend was
carried out and the results were shown. It can be
concluded that the angle of repose for all formulation
blends was obtained in the range of 20.02 to 22.32
thus falling in the range of official limits 25-30 (good
flow). Hence all formulation blends possess good flow
property.
Bulk density of the formulation blend plays an
important role in the compression of the powder. Bulk
density was carried out and the results were shown.
The bulk density of the formulations was found to be
in the range of 0.64g/cm3
to 0.71g/cm3
.
Tapped density also plays an important role in
knowing the compressibility of the formulation blend.
It was found to be in the range of 0.72g/cm3
to
0.83g/cm3
. It was noted that the tapped density of all
the formulations were greater than their respective
bulk density thus indicating that all the powder
formulation had a good compressibility.
Carr’s consolidation index was carried out and the
results were shown. The CCI was calculated based on
bulk density and tapped density. It was found to be in
the range of 10.22 to 14.81 indicating that all
formulation blends possess good flow property for
compression.
Hausner’s ratio is the ratio between tapped bulk
density and loose bulk density. Hausner’s ratio was
calculated for all formulation blends and reported. All
formulations having Hausner’s ratio < 1.25
Weight variation, Thickness, Hardness,
Friability, Disintegration Time, Water
absorption ratio and Wetting time
The % weight variation was calculated for all
formulations. All the formulations passed the weight
variation test as the percentage weight variation was
within the pharmacopoeia limits. The weights of all
formulations were found to be uniform with low
standard deviation values.
Thickness of all the formulations was found to be
2.33±0.14 to 2.52±0.03mm with low standard
deviation values.
The crushing strength of the uncoated tablets of each
batch ranged between 2.52±0.11 to 3.46±0.25 kg/cm2
.
This ensures good handling characteristics of all
batches.
The values of friability test were in the range from
0.45 to 0.69%. The percent friability of all the
formulations was less than 1% ensuring that the tablets
were stable.
The values of the disintegration time found in the
range 10 to 60 seconds.T13 formulation was found to
have less disintegration.
The formulations prepared shows water absorption
ratio in the range 87-109%, formulations containing
less superdisintegrant shows lower water absorption
ratio when compared formulations containing more
superdisintegrants, the water absorption ratio also
decreases due to less swelling property.
Wetting time is closely related to the inner
structure of the tablet. Promising formulations T13
S. no Formulations Wave number in
formulation (cm-1
)
Characteristic wave number
range(cm-1
)
Bond nature and bond
attributed
1 Pure drug 3292.48 3200-3400 NH stretching (2 amine)
2 CCS 1586.72 1400-1600 C=C ring stretch
Benzene
3 SSG 3274.36 3200-3400 OH stretching
(Bonded)
4 HPMC E 15 2897.56 2800-3000 C-H aldehyde stretching
5 Optimized
Tablet
1702.14 1600-1800 C=O ketone stretching
6 Optimized
Film
1039.87 1020-1250 C-N aliphatic stretching
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60
and F3 showed a wetting time of 8 and 14 seconds
respectively which facilitates faster dispersion in the
mouth.
In vitro drug release studies
The in vitro drug release study plays an important
part in the selection of best formulation among all. The
in vitro drug release study for tablets of Fexofenadine
Hydrochloride was carried out in 6.8pH phosphate
buffer as a diffusion medium. The drug release from
the formulation increased as the concentration of the
super disintegrant increased.
Stability Studies
The selected formulation T3 was subjected to
stability studies and the formulation was evaluated for
physical parameters like size, colour, hardness,
thicknesses were same. The percentage drug content
and % cumulative drug release was tested at 30 days,
60 days and 90days, there were no significant changes
in the values.
CONCLUSION
Rapid dispersible tablets of fexofenadine
hydrochloride were prepared using cross povidone,
cross carmellose sodium and sodium starch glycolate
as superdisintegrants in different concentrations by
Direct Compression method. Preformulation studies of
Fexofenadine Hydrochloride were performed, from the
FT-IR, the interference was verified and found that
polymers did not interfere with the drug. Finally, it can
be concluded that Fexofenadine Hydrochloride can be
formulated as Rapid Dispersible Tablets successfully
and gives best results. Also negligible side effects
makes it superior and effective candidate for pediatric,
geriatric, bedridden and psychotic patients.
REFERENCES
[1]. Slowson M, Slowson, S. What to do when patients cannot swallow their medications. Pharm Times. 51, 1985,
90-96.
[2]. Doheny K. You really expect me to swallow those horse pills? Am Druggist. 208, 1993, 34-35.
[3]. European Directorate for quality of medicines, pharmeuropa, 10(4), 547,1998
[4]. US Food and Drug Administration, CDER Data Standards Manual. 2003
[5]. European Directorate for Quality of Medicines (www.pheur.org), pharmeuropa,, 10(4), 1998, 547
[6]. Chang R.K., Guo X, Burnside B.A, Couch R. A.: Fast dissolving tablets. Pharm. Tech., 24(6), 2000, 52-58.
[7]. Kuchekar B.S, Bhise S.B, Arumugam V: Design of fast Dissolving Tablets Ind. J. Pharm. Edu, Article 7, 2001,
1.
[8]. Jaccard T.T, Leyder J: Une Nouvelle Forme Galenique: Le Lyoc. Ann. Pharm. Fr., 43(2), 1985, 123-131.
[9]. Remon J.P, Corveleyn S: Freeze- Dried Disintegrating Tablets. U.S. 6, 2000, 010,719.
[10]. News Release, Scherer Announces Launch of First U.S. Product using Zydis Technology September, 1996.
[11]. Gregory G.K.E., HoD: Pharmaceutical Dosage Form Packages. U.S. Patent 4, 1981, 305-502.
[12]. Yarwood R: Zydis –A novel, Fast Dissolving Dose Form. Man. Chem., 61, 1990, 36-37.
[13]. Seager H: Drug Delivery Products and the Zydis Fast- Dissolving Dosage Form. J.Pharm. Pharmacol., 50(4),
1998, 375-385.
[14]. Van Scoik K.G: Solid Pharmaceutical dosage in tablet triturate and form and method of producing same. US
Patent No. 5, 1992, 082,667.
[15]. Dobetti L: Fast–Melting Tablets: Development and Technologies. Pharm. Technol., Drug Delivery
supplement, 2001, 44-50.
[16]. Masaki K: Intrabuccally Disintegrating Preparation Production Thereof. US Patent: 5, 1995, 466,464.

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Fast Acting Fexofenadine Tablets

  • 1. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 49 International Journal of Farmacia Journal Home page: www.ijfjournal.com Formulation and in vitro evaluation of fast melting tablets of Fexofenadine *Yasmeen, Pamu Sandhya Shadan Women’s College of Pharmacy, Khairatabad, Hyderabad, Telangana 500004 *Corresponding author: Yasmeen *Email: yasmeen_mpharm016@yahoo.com Abstract Fexofenadine Hydrochloride is an antihistamine drug used in the treatment of hay fever and similar allergy symptoms. It does not readily pass through the blood-brain barrier and causes less drowsiness than first generation histamine-receptor antagonists. Fourteen batches of rapid dispersible tablets of Fexofenadine Hydrochloride were prepared using Cross Povidone, Cross carmellose Sodium and Sodium Starch Glycolate as Superdisintegrants in different concentrations and in different combinations by Direct Compression method. Preformulation studies of Fexofenadine Hydrochloride were performed, from the FT-IR; the interference was verified and found that Fexofenadine Hydrochloride did not interfere with the polymers used. Fexofenadine Hydrochloride formulated as Rapid Dispersible Tablets gives best results. Also negligible side effects makes it superior and effective candidate for pediatric, geriatric, bedridden and psychotic patients. Keywords: Fexofenadine hydrochloride, Super-disintegrants, Formulation and Evaluation. INTRODUCTION Many pharmaceutical dosages are administered in the form of pills, granules, powders, and liquids. Generally, a pill design is for swallowing intact or chewing to deliver a precise dosage of medication to patients. The pills, which include tablets and capsules, are able to retain their shapes under moderate pressure [1]. However, some patients, particularly pediatric and geriatric patients, have difficulty swallowing or chewing solid dosage forms. Many pediatric and geriatric patients are unwilling to take these solid preparations due to fear of choking. Hence orally dissolving tablets have come into existence [2, 3]. To fulfill these medical needs, formulators have devoted considerable efforts for developing a novel type of dosage form for oral administration known as Rapid Dispersible Tablets (RDT). This is an innovative technology where the dosage form containing active pharmaceutical ingredients disintegrates rapidly, usually in a matter of seconds, without the need for water, providing optimal convenience to the patient. Fexofenadine is a second- generation, long lasting H1-receptor antagonist (antihistamine) which has a selective and peripheral H1-antagonist action. Fexofenadine Hydrochloride is a white to off-white crystalline powder. Dose is 30mg. Its chemical name is 4-[1-hydroxy-4- [4(hydroxydiphenylmethyl)-1 piperidinyl] butyl]- (alpha). Its Molecular weight is 538.13 and Emperical formula is C32H39NO4 .HCL. Freely soluble in methanol and ethanol, slightly soluble in chloroform and water, insoluble in hexane. Bioavailability and Protein binding are 30-41% and 60-70% respectively. Half-life is 14.4hours. 80% Excretion is through feces. Unlike most other antihistamines, it does not enter the brain from the blood and therefore, does not cause drowsiness. Fexofenadine lacks the cardiotoxic potential of terfenadine, since it does not block the potassium channel involved in repolarization of cardiac cells [4].
  • 2. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 50 MATERIALS AND METHODS All the chemicals obtained and used are of analytical grade. Fexofenadine Hydrochloride, Magnesium stearate, Talc, Microcrystalline Cellulose, Cross Povidone, Sodium Starch Glycolate, Cross Carmellose Sodium, Aerosil, Mannitol, Hydroxyl propyl methyl cellulose E15 LV and Hydroxyl propyl methyl cellulose 5cps were obtained from Baris Pharmaceuticals, Hyderabad and Bright Pharmaceuticals [5]. Methods Preparation of Oral disintegrating tablets In the present study, the oral disintegrating tablets of Fexofenadine Hydrochloride are prepared by Direct compression method, using different polymer and concentrations. Preparation of tablets by the direct compression technique The steps followed in the formulation of ODT’s by direct compression technique includes: Dry screening, weighing, mixing, mixing of Super Disintegrants, lubricant and glidant then compressing [6]. Procedure All the required ingredients were passed through 40 mesh size to get uniform size particles and weighed accurately. Measured amount of drug, superdisintegrants, Avicel, sweetner and flavor except glidant and lubricant are mixed in increasing order of their weights in a mortar. To this mixture talc and magnesium stearate were added. The final mixture is manually shaken for 10mins in plastic bag. Final blend was compressed into tablets using 8mm s/c round, flat punches using Karnavathi, Rimek Compression Tablet Punching Machine [7]. Development of the formulation in the present study was mainly based on the type and concentration of polymers and properties of the drug. Various polymers in different concentrations were used so as to get tablets with good physical properties. In the following formulations cross povidone, sodium starch glycolate and cross carmellose sodium were used in 4%, 8% and 12% concentrations each then another set of formulations were done using combinations of two superdisintegrants in different concentrations [8]. Table 1: Formulation design of Fexofenadine Hydrochloride Rapid dispersible tablets Ingredients T1 T2 T3 T4 T5 T6 T7 T8 T9 Fexofenadine Hyrochloride 30 30 30 30 30 30 30 30 30 Cross povidone 8 16 24 - - - - - - Sodium starch glycolate - - - 8 16 24 Cross carmellose sodium - - - - - - 8 16 24 Magnesium stearate 2 2 2 2 2 2 2 2 2 Aerosil 2 2 2 2 2 2 2 2 2 Microcrystalline cellulose 155 147 139 154 146 138 153 145 137 Talc 2 2 2 2 2 2 2 2 2 Mannitol 1 1 1 2 2 2 3 3 3 Evaluation Weight variation test Method 20 tablets were randomly selected from each formulation and their average weight was calculated using digital balance (Denver, Germany). Then individual tablets were weighed and the individual weight was compared with an average weight, the variation in the tablet was expressed in terms of %deviation.
  • 3. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 51 Table 2: Limits of weight variation Average weight of tablet % Weight variation 130mg or less 10 More than 130mg, less than 324mg 7.5 More than 324mg 5 Thickness measurement Method Randomly 10 tablets were taken from each formulation and their thickness was measured using a digital screw guage, (Digimatic outside micrometer, Mitutoyo, Japan). The individual tablet was paced between two anvils of screw guage and sliding knob was rotated until the tablet was tightly fitted. The digital reading displayed was noted [9]. Hardness and Friability Method (Hardness) The tablet hardness of different formulations was measured using a Monsanto hardness tester. The tester consists of a barrel containing a compressible spring held between two plungers. The lower plunger was placed in contact with the tablet and a zero was taken [10]. The upper plunger was then forced against the spring by turning a threaded bolt until the tablet fractures. As the spring is compressed, a pointer rides along a guage in the barrel to indicate the force. The force of fracture is recorded, and the zero force reading is deducted from it. Generally, a minimum hardness of 4 kg is considered acceptable for uncoated tablets. The hardness for ODTs should be preferably 1-3 kg. Method (friability) This test is performed using a laboratory friability tester known as Roche Friabilator. 10 tablets were weighed and placed in a plastic chambered friabilator attached to a motor, which revolves at a speed of 25 rpm, dropping the tablets from a distance of 6 inches with each revolution. The tablets were subjected to 100 revolutions for 4 mins. After the process, these tablets were dedusted and reweighed. Percentage loss of tablet weight was calculated [11]. Drug content uniformity Five tablets were weighed individually and powdered. The powder equivalent to 30mg of fexofenadine hydrochloride was weighed and extracted in phosphate buffer 6.8pH and the concentration of drug was determined by measuring absorbance at 224nm by UV-Visible spectrophotometer [12]. Wetting time and water absorption ratio (R) Method Five circular tissue papers were placed in a Petri dish with a 10-cm diameter. Ten millimeters of water containing Eosin, a water-soluble dye, was added to the Petri dish. The dye solution is used to identify the complete wetting of the tablet surface. A tablet was carefully placed on the surface of tissue paper in the Petri dish at room temperature. The time required for water to reach the upper surface of the tablets and completely wet them was noted as the wetting time. To check for reproducibility, the measurements were carried out in replicated (n=6). The wetting time was recorded using a stopwatch [13]. The weight of the tablet before keeping in the Petri dish was noted (Wь) using Shimadzu digital balance. The wetted tablet from the Petri dish was taken and reweighed (Wa) using the same. The water absorption ratio, R, was determined according to the following equation: R = 100 (Wa – Wb) / Wb Where, Wb and Wa are the weight before and after water absorption respectively. Disintegration Time Disintegration time is considered to be one of the important criteria in selecting the best formulation. To achieve correlation between disintegration time In vitro and In vivo (in oral cavity) several methods were proposed, developed and followed at their convenience. One of the simple methods followed is described below [14].
  • 4. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 52 Method Disintegration time was also measured using a modified disintegration method. For this purpose, a Petri dish (10 cm diameter) was filled with 10ml of water. Tablet was carefully put in the centre of the Petri dish and the time for the tablet to completely disintegrate into find particles was moved using a pump watch [15]. Dissolution test Method Drug release from RDTs was studied by using USP type-II dissolution rate test apparatus at 50rpm (USP XXIII Dissolution Test Apparatus) using 900ml of phosphate buffer pH6.8 as dissolution medium. RDTs of desired formulation were taken and placed in the vessels of dissolution apparatus. Samples were collected from the vessels at different time intervals, replenished with same volume of the blank solution and analyzed using UV-Visible spectrophotometer. Drug concentration was calculated from the standard graph and expressed as % of drug dissolved or released. The release studies were performed in replicates and means values were taken [16]. Table 3: Details of in vitro drug release study Apparatus used USP XXIII dissolution test apparatus Dissolution Medium 6.8 pH Phosphate buffer Dissolution Medium Volume 900ml Temperature 37±0.5ºC Speed Of Paddle 50rpm Time Intervals 2,5,10,15,30,45,60mins Sample Withdrawn 5ml Absorbance Maximum λmax 224nm Stability Studies Stability of a drug is defined as the ability of a particular formulation, in a specific container, to maintain its physical, chemical, therapeutic and toxicological specifications. The purpose of stability testing is to provide evidence on how the quality of a drug substance varies with time under the influence of variety of environmental conditions and enables recommended storage conditions, re-test periods and shelf lives to be established. RESULTS AND DISCUSSIONS Preformulation studies Determination of solubility It was observed that it is sparingly soluble in water and chloroform, completely soluble in ethanol and methanol and insoluble in hexane. Determination of drug polymer compatibility studies using FTIR Drug excipient interactions play a crucial role with respect to the stability and potency of the drug. FTIR techniques have been used to study the physical and chemical interaction between the drug and excipients used.
  • 5. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 53 Fig 1: FT-IR spectra of Fexofenadine Hydrochloride Fig 2: FT-IR spectra of Cross carmellose Sodium 3292.483 284.976 2639.115 42.856 2084.592 1.151 1701.194 360.906 1401.248 75.752 1335.026 82.301 1277.952 182.482 1160.319 309.745 1067.963 80.747 983.601 58.165 964.925 96.991 832.457 103.714 744.582 190.934 695.342 -1.299 638.879 44.890 574.478 105.534 DrugFexofenadineHCL 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 90 80 70 60 50 Wavenumber %Transmittance 3390.115 4.236 2122.469 6.567 1586.724 69.285 1412.183 17.565 1320.255 115.206 1254.549 11.177 1104.627 493.440 1049.177 41.707 894.740 60.202 662.196 -0.002 614.115 46.633 418.859 46.556 405.532 2.395 CCS 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 100 90 80 70 60 50 40 Wavenumber %Transmittance 3274.368 1.188 2928.641 593.025 2086.931 16.339 1590.225 425.817 1322.721 253.482 1149.249 268.090 1076.700 96.910 996.157 1672.481 859.999 146.977 762.002 71.834 703.402 72.837 571.949 112.201 SSG 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 100 90 80 70 60 50 40 30 20 Wavenumber %Transmittance
  • 6. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 54 Fig 3: FT-IR spectra of Sodium Starch Glycolat Fig 4: FT-IR spectra of HPMC K 15 Fig 5: FT-IR spectra of optimized RDTof Fexofenadine Hydrochloride Fig 6: FT-IR spectra of optimized RDF of Fexofenadine Hydrochloride 2897.562 307.285 1374.508 -0.001 1313.619 40.954 1187.481 54.237 1050.195 3476.235 942.943 521.285 653.641 34.416 564.886 23.846 HPMCE15 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 100 80 60 40 Wavenumber %Transmittance 3292.953 159.029 1702.149 -0.005 1429.769 52.084 1314.534 81.456 1246.816 34.939 1203.381 58.816 1160.538 281.653 1103.854 263.988 1053.657 160.846 1029.727 83.617 662.628 69.484 608.540 27.901 557.150 87.664 518.482 45.067 434.055 44.642 OptimisedODT 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 100 90 80 70 60 50 40 30 Wavenumber %Transmittance 3248.469 0.907 2944.826 106.590 1330.894 7.541 1211.353 46.904 1110.593 177.038 1039.875 730.080 993.518 131.060 843.752 52.171 551.817 4.627 OPTIMISEDFILM 3800 3600 3400 3200 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 100 80 60 40 Wavenumber %Transmittance
  • 7. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 55 Determination of absorption maximum λmax In the preformulation study, it was found that the λmax of Fexofenadine hydrochloride by spectrophotometric method in 6.8pH phosphate buffer was found to be 224nm. Fig 7: λmax of Fexofenadine Hydrochodride in 6.8pH phosphate buffer Pre-compression parameters Table 4: Evaluation of the flow properties of powder blend for formulations T-1 to T-9 Post compression studies Table 5: Evaluation of tablets for weight variation, thickness, hardness and friability S. No Formulations *Weight variation (mg) *Thickness (mm) *Hardness (kg/cm2 ) Friability (%) 1 T1 199.10±0.20 2.38±0.03 2.56±0.13 0.45 2 T2 201.09±0.33 2.47±0.01 2.52±0.11 0.53 3 T3 198.80±0.34 2.5±0.02 3.46±0.25 0.49 4 T4 200.33±0.76 2.46±0.04 3.32±0.21 0.57 5 T5 200.34±0.48 2.38±0.12 2.91±0.15 0.68 6 T6 201.67±0.27 2.5±0.02 2.96±0.17 0.62 7 T7 200.43±0.71 2.33±0.14 3.46±0.25 0.51 8 T8 200.19±0.21 2.5±0.02 3.05±0.21 0.63 9 T9 199.26±0.20 2.4±0.02 3.04±0.21 0.65 *Values expressed as mean±SD, n=3 S. No Formulations Angle of repose (θ) Bulk density (gm/cc) Tapped density (gm/cc) Carr’s index (%) Hausner’s ratio 1 T1 21.43 0.65 0.72 10.22 1.11 2 T2 20.55 0.69 0.79 12.65 1.14 3 T3 21.45 0.69 0.81 14.81 1.17 4 T4 20.67 0.70 0.82 14.63 1.17 5 T5 20.84 0.64 0.72 11.11 1.12 6 T6 20.82 0.64 0.73 12.32 1.14 7 T7 22.29 0.65 0.74 12.16 1.13 8 T8 22.32 0.71 0.83 14.45 1.16 9 T9 21.27 0.70 0.80 12.50 1.14
  • 8. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 56 Table 6: Evaluation of the disintegration time, wetting time and water absorption ratios S. No Formulations Disintegration time (sec) Wetting time (sec) Water absorption ratio 1 T1 22 20 109 2 T2 20 18 100 3 T3 18 16 96 4 T4 38 36 97 5 T5 26 23 87 6 T6 19 22 107 7 T7 60 57 108 8 T8 55 50 99 9 T9 30 25 95 Table 7: Percentage Cumulative drug release of tablets in 6.8pH phosphate buffer Time (min) T1 T2 T3 T4 T5 T6 T7 T8 T9 2 30.67 43.65 50.36 33.12 68.85 56.3 64.05 69.02 70.15 5 39.15 58.05 64.2 46.24 87.75 61.4 71.95 73.15 82.05 10 50.9 76.95 76.11 66.1 90.1 84.65 74.4 86.75 86.6 15 67.06 87.15 83.49 74.94 99.2 89.7 87.95 91.85 90.2 30 84.23 91.5 100.01 96.8 98.57 98.1 96.45 96.6 96 45 91.35 97.65 101.55 102.4 102.15 101.3 101 101.15 102.35 60 98.84 101.3 104.2 - - - - 105.2 - Fig 8: Cumulative percentage drug release of T1-T3 with Cross Povidone 0 20 40 60 80 100 120 0 2 5 10 15 30 45 60 %cumulativedrugrelaese Time (min) % Drug Release of T1-T3 T1 T2 T3
  • 9. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 57 Fig 9: Cumulative percentage drug release of T4-T6 with Sodium Starch Glycolate Fig 10: Cumulative percentage drug release of T7-T9 with Cross Carmellose Sodium Comparison with marketed product Brand Name: Allegra Table 8: Comparison of Percentage Cumulative drug release of Optimized formulation (F13) of Fexofenadine Hydrochloride and the marketed tablet Time (min) % Cumulative Drug Release T13 Marketed Tablet 2 99.63 69.3 5 99.82 76.95 10 99.91 82.55 15 100.62 94.69 30 101.83 99.99 45 102.94 100.26 60 103.56 101.49 0 20 40 60 80 100 120 0 2 5 10 15 30 45 60 %cumulativedrugrelease Time (min) % Drug Release of T4-T6 T4 T5 T6 0 20 40 60 80 100 120 0 2 5 10 15 30 45 60 %cumulativedrugrelease Time (min) % Drug Release of T7-T9 T7 T8 T9
  • 10. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 58 Fig 11: Comparison of percentage drug release between optimized and marketed formulation Accelerated Stability Studies Table 9: Accelerated Stability Study data of Optimized Formulation Stability Period % Drug Content % In vitro Release Initial 98±0.05 100±0.01 30 Days 97±0.86 99±0.24 60 Days 97±0.64 99±0.18 90 Days 97±0.02 99±0.05 *Values expressed as mean±SD, n=3 Oral disintegrating drug delivery system have an advantage over the conventional drug delivery system in pediatric, elderly, bed ridden, mentally retarted and patients suffering with dysphagia. As these kind of patients need special attention and monitoring, in the present study an attempt has been made to formulate and evaluate Rapid Dispersible tablets and films of Fexofenadine Hydrochloride by Direct Compression method using different superdisintegrants in different concentrations. Solubility, Determination of of λ max , Construction of calibration curve, Drug polymer compatibility studies The solubility of Fexofenadine Hydrochloride reveals that it is sparingly soluble in water and chloroform, completely soluble in ethanol and methanol and insoluble in hexane. In the Preformulation studies, the lambda max of Fexofenadine Hydrochloride was determined by Spectroscopic Method and it was found to be 224nm with 6.8pH phosphate buffer. In this study at 224nm in 6.8pH phosphate buffer had good reproducibility in the concentration between 10-50µg/ml. Correlation between concentration and absorbance was found to be closer to 1 indicating that the method obeyed Beer-Lambert’s Law. Fourier-Transformed Infrared (FTIR) Spectrophotometer technique has been used to study the physical and chemical interaction between the drug and excipients used. 0 20 40 60 80 100 120 0 2 5 10 15 20 45 60 %cumulativedrugrelease Time (min) % Drug release of T3 and Marketed tablet T13 ALLEGRA
  • 11. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 59 Table 10: FT-IR data interpretation The FT-IR spectrum of pure drug and different excipients and the optimized tablet and film formulation were studied. There was no significant difference between the absorption peaks of pure drug and optimized formulation. The results concluded that there was no interaction between pure drug and excipients. Angle of repose, Bulk density, Tapped density, Carr’s compressibility index and Hausner’s Ratio The angle of repose for the formulation blend was carried out and the results were shown. It can be concluded that the angle of repose for all formulation blends was obtained in the range of 20.02 to 22.32 thus falling in the range of official limits 25-30 (good flow). Hence all formulation blends possess good flow property. Bulk density of the formulation blend plays an important role in the compression of the powder. Bulk density was carried out and the results were shown. The bulk density of the formulations was found to be in the range of 0.64g/cm3 to 0.71g/cm3 . Tapped density also plays an important role in knowing the compressibility of the formulation blend. It was found to be in the range of 0.72g/cm3 to 0.83g/cm3 . It was noted that the tapped density of all the formulations were greater than their respective bulk density thus indicating that all the powder formulation had a good compressibility. Carr’s consolidation index was carried out and the results were shown. The CCI was calculated based on bulk density and tapped density. It was found to be in the range of 10.22 to 14.81 indicating that all formulation blends possess good flow property for compression. Hausner’s ratio is the ratio between tapped bulk density and loose bulk density. Hausner’s ratio was calculated for all formulation blends and reported. All formulations having Hausner’s ratio < 1.25 Weight variation, Thickness, Hardness, Friability, Disintegration Time, Water absorption ratio and Wetting time The % weight variation was calculated for all formulations. All the formulations passed the weight variation test as the percentage weight variation was within the pharmacopoeia limits. The weights of all formulations were found to be uniform with low standard deviation values. Thickness of all the formulations was found to be 2.33±0.14 to 2.52±0.03mm with low standard deviation values. The crushing strength of the uncoated tablets of each batch ranged between 2.52±0.11 to 3.46±0.25 kg/cm2 . This ensures good handling characteristics of all batches. The values of friability test were in the range from 0.45 to 0.69%. The percent friability of all the formulations was less than 1% ensuring that the tablets were stable. The values of the disintegration time found in the range 10 to 60 seconds.T13 formulation was found to have less disintegration. The formulations prepared shows water absorption ratio in the range 87-109%, formulations containing less superdisintegrant shows lower water absorption ratio when compared formulations containing more superdisintegrants, the water absorption ratio also decreases due to less swelling property. Wetting time is closely related to the inner structure of the tablet. Promising formulations T13 S. no Formulations Wave number in formulation (cm-1 ) Characteristic wave number range(cm-1 ) Bond nature and bond attributed 1 Pure drug 3292.48 3200-3400 NH stretching (2 amine) 2 CCS 1586.72 1400-1600 C=C ring stretch Benzene 3 SSG 3274.36 3200-3400 OH stretching (Bonded) 4 HPMC E 15 2897.56 2800-3000 C-H aldehyde stretching 5 Optimized Tablet 1702.14 1600-1800 C=O ketone stretching 6 Optimized Film 1039.87 1020-1250 C-N aliphatic stretching
  • 12. Yasmeen et al / Int. J. of Farmacia, 2016; Vol-(2) 1: 49-60 60 and F3 showed a wetting time of 8 and 14 seconds respectively which facilitates faster dispersion in the mouth. In vitro drug release studies The in vitro drug release study plays an important part in the selection of best formulation among all. The in vitro drug release study for tablets of Fexofenadine Hydrochloride was carried out in 6.8pH phosphate buffer as a diffusion medium. The drug release from the formulation increased as the concentration of the super disintegrant increased. Stability Studies The selected formulation T3 was subjected to stability studies and the formulation was evaluated for physical parameters like size, colour, hardness, thicknesses were same. The percentage drug content and % cumulative drug release was tested at 30 days, 60 days and 90days, there were no significant changes in the values. CONCLUSION Rapid dispersible tablets of fexofenadine hydrochloride were prepared using cross povidone, cross carmellose sodium and sodium starch glycolate as superdisintegrants in different concentrations by Direct Compression method. Preformulation studies of Fexofenadine Hydrochloride were performed, from the FT-IR, the interference was verified and found that polymers did not interfere with the drug. Finally, it can be concluded that Fexofenadine Hydrochloride can be formulated as Rapid Dispersible Tablets successfully and gives best results. Also negligible side effects makes it superior and effective candidate for pediatric, geriatric, bedridden and psychotic patients. REFERENCES [1]. Slowson M, Slowson, S. What to do when patients cannot swallow their medications. Pharm Times. 51, 1985, 90-96. [2]. Doheny K. You really expect me to swallow those horse pills? Am Druggist. 208, 1993, 34-35. [3]. European Directorate for quality of medicines, pharmeuropa, 10(4), 547,1998 [4]. US Food and Drug Administration, CDER Data Standards Manual. 2003 [5]. European Directorate for Quality of Medicines (www.pheur.org), pharmeuropa,, 10(4), 1998, 547 [6]. Chang R.K., Guo X, Burnside B.A, Couch R. A.: Fast dissolving tablets. Pharm. Tech., 24(6), 2000, 52-58. [7]. Kuchekar B.S, Bhise S.B, Arumugam V: Design of fast Dissolving Tablets Ind. J. Pharm. Edu, Article 7, 2001, 1. [8]. Jaccard T.T, Leyder J: Une Nouvelle Forme Galenique: Le Lyoc. Ann. Pharm. Fr., 43(2), 1985, 123-131. [9]. Remon J.P, Corveleyn S: Freeze- Dried Disintegrating Tablets. U.S. 6, 2000, 010,719. [10]. News Release, Scherer Announces Launch of First U.S. Product using Zydis Technology September, 1996. [11]. Gregory G.K.E., HoD: Pharmaceutical Dosage Form Packages. U.S. Patent 4, 1981, 305-502. [12]. Yarwood R: Zydis –A novel, Fast Dissolving Dose Form. Man. Chem., 61, 1990, 36-37. [13]. Seager H: Drug Delivery Products and the Zydis Fast- Dissolving Dosage Form. J.Pharm. Pharmacol., 50(4), 1998, 375-385. [14]. Van Scoik K.G: Solid Pharmaceutical dosage in tablet triturate and form and method of producing same. US Patent No. 5, 1992, 082,667. [15]. Dobetti L: Fast–Melting Tablets: Development and Technologies. Pharm. Technol., Drug Delivery supplement, 2001, 44-50. [16]. Masaki K: Intrabuccally Disintegrating Preparation Production Thereof. US Patent: 5, 1995, 466,464.