Friday, December 1, 2023

# STP FOR PREGABALIN CAPSULES

1.0) Description: Visual

2.0) Average Weight: Check weight of 20 Capsules at randomly and calculate the average weight by formula :                                                                                           wt of 20 tablets (gm) x 1000 / 20. found avg. wt in mg

3.0) Average Fill: Check weight of 20 Capsules at randomly. And calculate the average weight by above formula and subtract empty weight of capsule from average weight.

4.0) Uniformity of weight:

Weigh 20 capsules 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.

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

Theoretical weight

 Average weight of capsules Percentage deviation 300 mg or less 10.0 % More than 300 mg 7.5%

5.0) Identification Test:

In the assay, the principal peak in the chromatogram obtained with the test solution corresponds to the principal peak in the chromatogram obtained with the reference solution.

6.0)      Disintegration Time:

Unless otherwise stated in the individual monograph, introduce one capsule 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 capsules fail to disintegrate, repeat the test on 12 additional capsules; not less than 16 of the total of 18 capsules tested disintegrate.

If the capsules 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 capsules in the repeat test disintegrate.

7.0)      Dimension of Capsule:

Length and diameter are determined by vernier in mm.

8.0)      Dissolution:

Medium: 900ml of 0.05 M HCl,

Time: 30 minutes

Speed: 50 rpm

Withdraw a suitable volume of the medium and filter.

Determine by liquid chromatography.

Test solution: Use the filtrate and dilute, if necessary, with the dissolution medium.

Reference solution: Dissolve a quantity of pregabalin reference standard in the dissolution medium and dilute with the dissolution                    medium to obtain a solution having a known concentration similar to the expected concentration of the test solution.

Chromatographic system:

• A stainless steel column 25cmX 4.6mm, packed with octadecylsilane bonded to porous silica (5µm) ( such as Inertsil ODS-3,
• Mobile phase: a mixture of 92 volumes of solution containing 2.72g of potassium dihydrogen orthophosphate in 900ml of water, add 2ml of triethylamine and adjusted to pH 6.0 with O.P.A., 5 volumes of methanol and 3 volumes of acetonitrile,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 205nm,
• Injection volume: 100µl

Inject the reference solution. The test is not valid unless the theoretical plates of the principal peak is not less than 2000, tailing factor is not more than 2.0 and the relative standard deviation of replicate injections is not more than 2.0 per cent.

Inject the reference solution and the test solution.

Calculate the content of pregabalin.

Limit: NLT 75% of the stated amount of Pregabalin.

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: Dissolve 1.2g of potassium dihydrogen phosphate in 1000ml water, adjusted pH to 6.9 with dilute potassium hydroxide.

Test solution: Weigh and disperse a quantity of the contents of capsules containing about 750mg of pregabalin, in about 25ml of the solvent mixture, with the aid of ultrasound for 30 minutes and dilute to 50ml with the solvent mixture.

Reference solution (a): A 0.015 per cent w/v solution of pregabalin reference standard in the solvent mixture.

Reference solution (b): Dissolve 4.5mg of lactam reference standard in 10ml of the solvent mixture.

Reference solution (c): Dissolve 750mg of pregabalin reference standard in 30ml of solvent mixture. Add about 5ml of reference solution (b) and dilute to 50ml with the solvent mixture.

Chromatographic system:

• A stainless steel column25cmX4.6mm, packed with octadecylsilane bonded to porous silica (5µm) ) (such as Intersil ODS-3V),
• Flow rate: 1ml per minute,
• Mobile phase: a mixture of 90 volumes of the solvent mixture and 10 volumes of acetonitrile,
1. Acetonitrile,
• A gradient programme using the conditions given below,
• Spectrophotometer set at 210nm,
• Injection volume: 20µl

 Time (in min.) Mobile phase A (per cent v/v) Mobile phase B (per cent v/v) 0 100 0 5 100 0 25 35 65 30 100 0 40 100 0

The relative retention time with reference to lactam peak for lactose conjugate inpurity is about 0.75.

Inject reference solution (a). The test is not valid unless the theoretical plates is not less than 3000, the tailing factor is not more than 2.0 and the relative standard deviation of replicate injections is not more than 2.0 per cent.

Inject reference solution (a), (c) and test solution. In the chromnatogram obtained with the test solution, the area of the peak due to lactam multiplied with relative response factor, 0.07 is not more than 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.5 per cent), the area of lactose conjugate impurity peak multipliued with relative response factor, 0.05 is not more than 1.5 times the area of the principal peak in the in the chromatogram obtained with reference solution (a) (1.5 per cent). The area of any other secondary peak is not more than the area of the principal peak in the chromatogram obtained with reference solution (a) (1.0 per cent) and the sum of areas of all the secondary peaks is not more than 2.5 times the area of the principal peak in the chromatogram obtained with reference solutrion (a) (2.5 per cent). Ignore any peak with an area less than 0.05 times of the area of principal peak in the chromatogram obtained with reference solution (a) (0.05 per cent).

11.0)    Assay: Determined by liquid chromatography.

Test solution: Mix the contents of 20 capsules. Disperse a quantity of powder containing about 200mg of pregabalin with 35ml of the mobile phase, sonicate for 10 minutes and dilute to 50ml with the mobile phase.

Reference solution: A 0.4 per cent w/v solution of pregabalin reference standard in the mobile phase.

Chromatographic system:

• A stainless steel column 25cmX 4.6mm, packed with octadecylsilane bonded to porous silica (5µm) ( such as Inertsil ODS-3,
• Mobile phase: a mixture of 92 volumes of solution containing 2.72g of potassium dihydrogen orthophosphate in 900ml of water, add 2ml of triethylamine and adjusted to pH 6.0 with O.P.A., 5 volumes of methanol and 3 volumes of acetonitrile,
• Flow rate: 1ml per minute,
• Spectrophotometer set at 205nm,
• Injection volume: 20µl

Inject reference solution. The test is not valid unless the theoretical plates are not less than 2000, tailing factor is not more than 2.0 and the relative standard deviation of replicate injections is not more than 2.0 per cent.

Inject the reference solution and the test solution.

Calculate the content of Pregabalin in the capsules.

Acceptance criteria: 90.0%-110.0%

12.0)    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

inHg: Inch of Mercury

rpm: Rounds per minute

CFU: Colony forming unit

HCl: Hydrochloric acid

w/v: Weight/Volume

v/v: Volume/Volume

O.P.A.: orthophosphoric acid