FORMULATION AND EVALUATION OF FAST DISSOLVING ORAL FILMS CONTAINING LOSARTAN POTASSIUM.

The fast dissolving oral film were prepared using different polymers like PVA, PVP, HPMC, Carbopol, Pectin and Tragacanth by solvent casting method. The fast Dissolving oral film evaluated for folding endurance, swelling index, surface pH, in vitro disintegration time, drug content, drug polymer compatibility by FTIR Study, Scanning electron microscopy and in vitro drug release. The physical appearance and folding endurance properties were found to be good and electron microscopy shows that films are clear, colourless with smooth surface without any scratches .The average folding endurance time within the range of 112 to 208.The drug content showed uniform mixing of drug in all prepared fast dissolving films. The invitro drug release showed 78 to 96 % drug release within 5 minutes. Drug release obeys the first order kinetics. The prepared films were stable. Hence it can be inferred that the fast dissolving oral film of losartan potassium may produce the rapid action thereby improving bioavailability and enhance the absorption by avoiding the first pass effect.


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industry for improved solubility/ stability, biological half life and bioavailability enhancement of drugs⁴.Nearly 35-50 percent of the general population, especially the elderly and children suffer from dysphagia or difficulty in swallowing, which results in high incidence of non-compliance and ineffective therapy.Other group who may experience problems in swallowing conventional oral dosage form are the patients with reduced liquid intake or patients suffering from nausea, as well as patients travelling or who do not have easy access to water.The swallowing problems are also common in some cases such as patients with motion sickness, sudden episodes of allergic attack or coughing and due to no access of water.Many pharmaceutical dosage forms are administered in the form of pills, Granules, powders and liquids.Generally, a pill is designed for swallowing intact or Chewing to deliver a precise dosage of medication to patients.The pills, which include tablet and capsules, are able to retain their shapes under moderate pressure.However, some Patient, particularly pediatric and geriatric patients, have difficulty in swallowing or chewing solid dosage forms⁵,⁶.Many pediatric and geriatric patients are unwilling to take these solid preparations due to fear of choking⁷.Although oral disintegrating tablets have an advantage of administration without choking and fast disintegration; the disintegrated materials contained in them are insoluble and remain same until swallowing.In such cases formulation of fast dissolving film will be advantageous ⁸ , ⁹ .Hence orally dissolving tablets have come into existence.Even with these Differences , most of the existing oral dissolving drug delivery systems are in the form of solid tablets and designed to dissolve/disintegrate in the patient's mouth without the need to drink or chew.However, the fear of taking solid tablets and the risk of choking for certain patient populations still exist despite their short disintegration or dissolution times.Hence mouth dissolving oral film drug delivery is a better alternative in such cases .Many drugs given orally are poor in bioavailability because of the pH of the stomach, the presence of enzymes, and extensive first-pass metabolism.Traditionally, these drugs have been administered by parenteral route, which invariably lead to poor patient compliance .This made the pharmaceutical industries to look for alternative routes of drug delivery system.Intra oral fast-dissolving drug delivery system where in the dosage form (film) will be placed on the surface of the tongue or in the oral/buccal cavity, where drug release rapidly for local and systemic absorption.

Method:-
Oral fast dissolving film was prepared by solvent casting method.Aqueous solution I was prepared by dissolving film forming polymer, in specific proportion in distilled water and allowed to stirred for 3 hours and kept for 1 hour to remove all the air bubble entrapped or remove bubbles.Aqueous solution II was prepared by dissolving the pure drug, sweetener, and plasticizer in specific proportion in distilled water.The aqueous solution I and II were mixed and stirred for 1 hour.The solution were cast on to 9cm diameter Petri dish and were dried in the oven at 45⁰C for 12 hours.The film was carefully removed from surface of petridish and cut according to size required for testing(square film 1.5 cm length,1.5cmwidth).The samples were stored in glass container maintained at a temperature 30⁰C and relative humidity 60% ±5% until further analysis.

Formulation of fast dissolving film of losartan potassium: Calculation of dose for losartan potassium:
The dose of losartan potassium is 25 mg.Therefore amount of Losartan potassium required in 3cm(1.5x1.5) is 25 mg. 1. Area of film of 1.5X1.5 sq.cm is 2.25 sq.cm. 2. Area of petridish of 6cm diameter is 28.26 sq.cm. 3. Amount of drug present in 2.25 sq.cm of film is 25 mg. 4. Amount of drug present in 28.26 sq.cm of petridish is 314 mg.Therefore, 2.25 sq.cm of film should contain 25 mg of drug.It is fixed for all formulations.

Table 1:-Composition of various formulations
Result & Discussion:-Standard plot of Losartan potassium in PH 6.8 phosphate buffer: 100 mg of losartan potassium was accurately weighed and dissolve into 100 ml volumetric flask containing pH 6.8 buffer solution to get a concentration of (1000 µg/ml) i.e. stock solution-I.from this 1 ml was withdrawn and diluted to 100 ml with pH 6.8 phosphate buffer, to get a concentration of (10 µg/ml) i.e.Stock solution-II.

Calibration curve in ph 6.8 phosphate buffer solution:
From the stock solution-II, 1,2,3,4,5,6,7,8and 9ml sample were withdrawn and volume was made up to the mark with pH 6.8 phosphate buffer.This solution gives 1,2,3,4,5,6,7,8,and 9 µg/ml concentration of losartan potassium.The absorbance of these solutions measured in UV at 203 nm using pH 6.8 phosphate buffer as blank.It is clear from the below observation of the below values of characteristics absorption bands for different functional groups and bonds of the drug and its polymer that is most of the cases there is no appreciable change in the position of the bands.Even if negligible deviation exist, its due to the different types of the polymers used for the study.

Moisture uptake:
All the films are free from the moisture uptake and there is no evidence of Moisture attack in the prepared films and data shown in table 4.

Thickness of films:
The thickness of the film was measured using vernier calipers.The thickness was almost uniform in all the formulations and values ranges from 0.7 ± 0.057 mm to 1.1 ± 0.100 mm.The standard deviation values indicated that all the formulations were within the range.The results of thickness for films were shown in Table 4.

Folding endurance:
The folding endurance of the films was determined by repeatedly folding a Small strip of films at the same place till it breaks and the folding endurance data of all the films is given in table 4.Among all the formulations, Formulation F1 to F3 showed minimum folding Endurance time which is indicate that these fast dissolving films are excellent in Flexibility as compared to other formulations.The drug content uniformity was performed for all the 15 formulations and Results are shown in Table 5.The percentage drugs content of the fast dissolving Films were found to be between 88.33% ± 0.027 to 98.68% ± 0.034 of losartan potassium.The results were within the range and that indicated uniformity of mixing and given in table.

In vitro disintegration time of films:
The in vitro disintegration time is calculated by the time taken by film to Under go complete disintegration.Electrolab Disintegration test apparatus (USP) maybe used for this study.The disintegration time of different formulation was shown in table 5.The in vitro disintegration time of all the formulations within the range of 16 ± 1.528 to 49 ± 2.887 seconds fulfilling the official requirements.As the concentration of the super disintegrant increases the in vitro disintegration time of the film also decreases.

Swelling index:
The studies for swelling index is carried out in pH 6.8 phosphate buffer solution.
The formulation F14 and F15 showed higher swelling index as compared to the other formulations due to the more water absorption of the super disintegrants.

Stability studies:
The selected formulations was evaluated for short term stability studies which was stored at 40⁰C at 75% RH tested for 3 month and were analyzed periodically for their physical parameters, in vitro dispersion time and drug content at 30 days interval.The residual drug contents of formulations were found to be within the permissible limits and the values were shown in the tables below. 1061

Conclusion:-
In the present study fast dissolving drug delivery system of Losartan potassium were successfully developed in the form of fast dissolving oral films which offers a suitable and practical approach in serving desired objective of faster disintegration and dissolution characteristics with increase in patient compliance by avoiding the first pass metabolism and enhance the bioavailability of the drug.
DRUG AND EXCEPIENT COMPATIBILITY STUDIESDrug-excipient compatibility studies lay the foundation for designing a chemically stable formulation for clinical and commercial development.Drug excipient compatibility studies are conducted during preformulation to select the most appropriate excipients.

Table 11 :
-Stability data of formulation F1

Table 12 :
-Stability data of formulation F11

Table 13 :
-Stability data of formulation F15 Fig 16:-Photograph of buccal films of Propranolol Hcl