## STP FOR ETORICOXIB TABLETS

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 peaks in the chromatogram obtained with the reference solution.

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 buffer solution prepared by dissolving 1.38g of monobasic sodium phosphate and 10g of sodium lauryl sulphate in 1000ml of water, adjusted to pH 7.0 with 1M sodium hydroxide.

Speed: 100 rpm

Time: 45 minutes

Limit: NLT 75% of the labeled amount of Etoricoxib.

Withdraw a suitable volume of the medium and filter. Measure the absorbance of the filtered solution, suitably diluted with the dissolution medium, if necessary, at the maximum at about 240nm. Calculate the content of Etoricoxib in the medium from the absorbance obtained from a solution of known concentration of etoricoxib reference standard in the dissolution medium in such manner to get similar concentration of the test solution.

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)    Assay: Determined by liquid chromatography.

Test solution: Weigh and powder 20 tablets. Disperse a quantity of powder containing 50mg of EToricoxib with 50ml of methanol with the aid of ultrasound and dilute to 100ml with methanol. Dilute 1ml of this solution to 10ml with methanol.

Reference solution: A 0.005 per cent w/v solution of etoricoxib reference standard in methanol.

Chromatographic system:

• A stainless steel column 25cm X4.6mm, packed with octadecylsilane bonded to porous silica (5µm),
• Mobile Phase: a mixture of 55 volumes of a buffer solution prepared by dissolving 6.8 g of potassium dihydrogen orthophosphate and 8.7g of dipotassium hydrogen orthophosphate in 1000ml of water, adjusted to pH 3.5 with O.P.A., and 45 volumes of acetonitrile,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 220nm,
• Injection volume: 20µl

Inject reference solution. The test is not valid unless the relative standard deviation for replicate injections is not more than 2.0 per cent.

Inject the reference solution and test solution.

Calculate the contents of Etoricoxib in the tablets.

Alternative Method: By UV Spectrophotometer

Test Solution: Weigh and powder 20 tablets. Weight sample equivalent to 100mg of Etoricoxib 100ml volumetric flask add 20ml methanol into it and sonicate to dissolve the test sample. Make up to mark with 0.1 M HCl. Filter and dilute 1ml of this solution to 50ml in 0.1 M HCl.

Reference Solution: Weigh 100mg of reference standard of Etoricoxib 100ml of volumetric flask. Add 20ml methanol into it and sonicate to dissolve. Make up to mark with 0.1 M HCl. Dilute 1ml of this solution to 50ml with 0.1 M HCl.

Check Absorbance of test as well as reference standard at about 270nm in UV Spectrophotometer.

Calculate the content of Etoricoxib in the tablets.

Formula:

Abs. of Test      STD Wt.(mg) 1            100             50      Potency

—————–X————–X——-X—————X——–X———–X Average wt.

Abs. of STD        100            50     Test Wt.(mg)     1           100

Acceptance criteria: 95.0%-105.0%

13.0)  Abbreviations:

Wt.: Weight

mg: Miligram

ml: Milileter

STD: Standard

inHg: Inch of Mercury

rpm: Rounds per minute

CFU: Colony forming unit

O.P.A.: Orthophosphoric acid

HCl: hydrochloric acid