## STP FOR LEVOCETIRIZINE DIHYDROCHLORIDE AND MONTELUKAST SODIUM TABLETS IP

1.0)  Description: Visual

2.0)  Average Weight: Check weight of 20 tablets at randomly and calculate the average weight by formula :

wt of 20 tablets (gm) x 1000 / 20. found avg. wt in mg

3.0)    Uniformity of weight:

Weigh 20 tablets selected at random and calculate the average weight. Not more than two of the individual weights deviate from the average weight by more than the percentage shown in table.

Tablets were weighed individually and the percentage of deviation of its weight from the average weight was determined for each tablet. Formula for calculate the percentage of deviation = (experimental weight – theoretical weight)    x 100

Theoretical weight

 Average weight of tablets Percentage deviation More than 80mg but Less than 250mg 7.5% 250mg or More 5%

4.0) Identification Test:

In the assay, the principal peaks in the chromatogram obtained with the test solution correspond to the principal peaks in the chromatogram obtained with reference solution (c).

5.0)      Hardness:

The standard method used for tablet hardness testing is compression testing. The tablet is placed between two jaws that crush the tablet. The machine measures the force applied to the tablet and detects when it fractures. Although compressive force is applied to the tablet, along the diameter of the tablet at right angles to the applied force.

6.0)      Disintegration Time:

Unless otherwise stated in the individual monograph, introduce one tablet into each tube and add a disc to each tube. The assembly is suspended in the liquid medium in a suitable vessel, preferably a 1-litre beaker. The volume of liquid is such that the wire mesh at its highest point is at least 15mm below the surface of the liquid, and at its lower point is at least 25mm above the bottom of the beaker. At no time should the top of the basket-rack assembly become submerged. There is a thermostatic arrangement for heating the liquid and maintaining the temperature at 37±2°.

If 1 or 2 tablets fail to disintegrate, repeat the test on 12 additional tablets; not less than 16 of the total of 18 tablets tested disintegrate.

If the tablets adhere to the disc and the preparation under examination fails to comply, repeat the test omitting the disc. The preparation complies with the test if all the tablets in the repeat test disintegrate.

7.0)      Dimension of Tablet:

Length, breadth and thickness are determined by vernier in mm

8.0)      Dissolution:

Medium: 900ml of 1.0 per cent w/v sodium lauryl sulphate in water,

Time: 45minutes

Speed: 50 rpm

Withdraw a suitable volume of the medium and filter.

Determine by liquid chromatography.

Test solution: Dilute the filtrate if necessary, with the methanol.

Reference solution (a): A 0.57 per cent w/v solution of montelukast sodium reference standard in methanol.

Reference solution (b): A 0.028 per cent w/v solution of levocetirizine HCl reference standard in methanol.

Reference solution (c): Dilute a suitable quantity of reference solution (a) and (b) with dissolution medium to obtain a solution having similar                                                                                         concentration as that of test solution.

Use chromatographic system as described under assay, using 100 µl injection volumes.

Inject the reference solution and the test solution.

Calculate the content of Levocetirizine DiHCl and Montelukast sodium.

Limit: NLT 75% of the stated amount of Levocetirizine DiHCl and Montelukast sodium.

9.0)      Leak test:

The apparatus is used to test for the integrity of packed strips, blisters and Alu-Alu Blister pack containing tablets. Ensure apparatus bath is filled with purified water upto mark indicated and add 0.5% crystal violet solution in water. Samples are placed into the desiccators and the lid is placed in position. The pump starts to produce a vacuum 15inHg inside the desiccators and the vacuum is held for 1 minute. The sample remains at the required vacuum level for given time interval buzzer will sound after time is over and will cut off the vacuum pump. As the package is immersed in a colored dye solution the venting of the desiccators will allow any holes to be penetrated by the dye and the contents of the flexible packaging will also be stained with the same coloring material.

Examine all the strips for any leakage by opening the pockets manually. If anyone pocket shows evidence of leakage, reject the sample, stop the Blister / Strip machine and immediately take corrective action.

10.0)    Related substance:

Determined by liquid chromatography.

Solvent mixture: A mixture of 30 volumes of a buffer solution prepared by dissolving 0.7791gm of ammonium acetate in 1000ml of water and add 0.1 ml of G.A.A and 70 volumes of acetonitrile.

Test solution: Weigh and powder 20 tablets. Disperse a quantity of powder containing 25mg of Montelukast sodium in a 100.0ml volumetric flask, add 70.0ml of solvent mixture and sonicate for 15 minutes and make to volume with solvent mixture, mix and centrifuge. Dilute 5.0ml of this solution to 25.0ml with the solvent mixture.

Reference solution (a): A 0.25 per cent w/v solution of montelukast sodium reference standard in the solvent mixture.

Reference solution (b): A 0.125 per cent w/v solution of levocetirizine diHCl reference standard in the solvent mixture.

Reference solution (c): Dilute reference solutions (a) and (b) with the solvent mixture to obtain a solution having a known concentration similar to the test solution.

Chromatographic system:

• A stainless steel column 25cmX4.6mm, packed with octadecylsilane bonded to porous silica (5µm)
• Mobile phase: a mixture of 60 volumes of a buffer solution prepared by dissolving 0.7791gm of ammonium acetate in 1000ml of water and add 0.1ml of glacial acetic acid and 40 volumes aceonitrile
1. Acetonitrile,
• A gradient programme using the conditions given below,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 240nm,
• Injection volume: 20µl

 Time (in minutes) Mobile phase A ( per cent v/v) Mobile phase B (Per cent v/v) 0 100 0 7 100 0 8 55 45 24 55 45 25 10 90 29 10 90

Inject the test solution. The area of any secondary peak is not more than 2.0 per cent and the sum of area of all the secondary peaks is not more than 4.0 per cent, calculate by area normalization.

11.0)    Uniformity of content:

Determine by liquid chromatography, using the chromatographic system as described under assay.

Test solution: Disperse one tablet in 100.0ml of volumetric flask. Add 25ml of solvent mixture and sonicate for about 10 minutes with intermittent shaking. Dilute to volume with solvent mixture, mix and centrifuge.

Reference solution: Dissolve 25mg of montelukast sodium reference standard and 12.5mg of levocetirizine DiHCl reference standard and dilute to 100.0ml with solvent mixture. Dilute 5.0ml of this solution tom 25.0ml with the mobile phase.

Chromatographic system:

• A stainless steel column 25cmX4.6mm, packed with octadecylsilane bonded to porous silica (5µm)
• Mobile phase: a mixture of 60 volumes of a buffer solution prepared by dissolving 0.7791gm of ammonium acetate in 1000ml of water and add 0.1ml of glacial acetic acid and 40 volumes aceonitrile
1. Acetonitrile,
• A gradient programme using the conditions given below,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 240nm,
• Injection volume: 20µl
 Time (in minutes) Mobile phase A ( per cent v/v) Mobile phase B (Per cent v/v) 0 100 0 7 100 0 8 55 45 24 55 45 25 10 90 29 10 90

Inject the reference solution and test solution.

Calculate the content of levocetirizine DiHCl and Montelukast sodium in the tablets.

12.0)    Assay:

Determined by liquid chromatography.

Solvent mixture: A mixture of 30 volumes of a buffer solution prepared by dissolving 0.7791gm of ammonium acetate in 1000ml of water and add 0.1 ml of G.A.A and 70 volumes of acetonitrile.

Test solution: Weigh and powder 20 tablets. Disperse a quantity of powder containing 25mg of Montelukast sodium in a 100.0ml volumetric flask, add 70.0ml of solvent mixture and sonicate for 15 minutes and make to volume with solvent mixture, mix and centrifuge. Dilute 5.0ml of this solution to 25.0ml with the solvent mixture.

Reference solution (a): A 0.25 per cent w/v solution of montelukast sodium reference standard in the solvent mixture.

Reference solution (b): A 0.125 per cent w/v solution of levocetirizine diHCl reference standard in the solvent mixture.

Reference solution (c): Dilute reference solutions (a) and (b) with the solvent mixture to obtain a solution having a known concentration similar to the test solution.

Chromatographic system:

• A stainless steel column 25cmX4.6mm, packed with octadecylsilane bonded to porous silica (5µm)
• Mobile phase: a mixture of 60 volumes of a buffer solution prepared by dissolving 0.7791gm of ammonium acetate in 1000ml of water and add 0.1ml of glacial acetic acid and 40 volumes aceonitrile
1. Acetonitrile,
• A gradient programme using the conditions given below,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 240nm,
• Injection volume: 20µl

 Time (in minutes) Mobile phase A ( per cent v/v) Mobile phase B (Per cent v/v) 0 100 0 7 100 0 8 55 45 24 55 45 25 10 90 29 10 90 29.1 100 0 35 100 0

Inject reference solution(c). The test is not valid unless the column efficiency is not less than 2000 theoretical plates, the tailing factor is not more than 2.0 and the relative standard deviation for replicate injections is not more than 2.0 per cent.

Inject reference solution (c) and the test solution.

Calculate the content of Montelukast sodium and Levocetirizine DiHCl in the tablet.

Acceptance criteria: 90.0%-110.0%

13.0)    MICROBIOLOGICAL PURITY:

Perform the test according to requirements of IP,

Total aerobic Microbial count (TAMC): NMT 103 CFU/g

Total combined yeasts/Moulds count (TYMC): NMT 102 CFU/g

Pathogens: in 1gm drug.

Escherichia Coli – Should be absent

Pseudomonas aeroginosa – Should be absent

Salmonella – Should be absent

Staphylococcus aureus– Should be absent

Abbreviations:

Wt.: Weight

mg: Miligram

ml: Milileter

STD: Standard

inHg: Inch of Mercury

rpm: Rounds per minute

CFU: Colony forming unit

G.A.A.: Glacial acetic acid