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.
Weigh the tablets individually and calculate the percentage of deviation for each tablet. By using formula = (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% |
- Identification Test:
In the assay, the principal peak in the chromatogram obtained with the test solution corresponds to the peak 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:
Apparatus: Paddle
Medium: 900ml of 0.1 M Hydrochloric acid.
Time: 45 minutes
Speed: 50 rpm
Limit: NLT 80% of the stated amount of Citicoline.
Withdraw a suitable volume of the medium and filter. Dilute the filtrate if necessary, with dissolution medium. Measure the absorbance of the resulting solution at the maximum at about 280nm. Calculate the content of Citicoline in the medium from the absorbance obtained from a solution of known concentration of citicoline sodium reference standard.
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 up to 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 substances:
Note: Determine water content of citicoline sodium reference standard before use and calculate the potency.
Test solution: Disperse a quantity of the powdered tablets containing 100mg of citicoline in the mobile phase with the aid of ultrasound for 30 minutes and dilute to 200ml with the mobile phase and filter.
Reference solution (a): Dissolve a quantity of cilticoline sodium reference standard in the mobile phase to obtain a solution containing 0.0005 per cent w/v of citicoline.
Reference solution (b): A solution containing 0.00025 per cent w/v each of citicoline sodium reference standard and 5-cytidylic acid reference standard in the mobile phase.
Chromatographic system:
- A stainless steel column 25cm X4.6mm, packed with octadecylsilane bonded to porous silica (5µm)
- Mobile phase: a mixture of 95 volumes of buffer solution prepared by dissolving 1.697g of tetrabutylammonium hydrogen sulphate in 1000ml of water, add 2ml of triethylamine and adjusted to pH 6.0 with dilute acetic acid and 5 volumes of methanol.
- Flow rate: 0.8ml per minute,
- Spectrophotometer set at 270nm,
- Injection volume: 20µl
Equilibrate the column with mobile phase for at least 90 minutes. Inject reference solutions (a) and (b). The test is not valid unless the tailing factor is not more than 2.0, the relative standard deviation for replicate injections is not more than 3.0 per cent in the chromatogram obtained with the reference solution (a) and the resolution between the principal peak and obtained with reference solution (b).
Inject reference solution (a) and the test solution. In the chromatogram obtained with the test solution, the area of peak due to 5-cytidylic acid multiplying by correction factor of 0.7 is not more than 1.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (1.5 per cent). The area of any other secondary peak 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) and the sum of the areas of all the secondary peaks other than the 5-cytidylic acid peak is not more than twice the area of the principal peak in the chromatogram obtained with reference solution (a) (2.0 per cent).
11.0) Assay: Determined by liquid chromatography.
Note: Determine water content of citicoline sodium reference standard before use and calculate the potency.
Test solution: Weigh and powder 20 tablets. Disperse a quantity of the powder containing 100mg of citicoline in the mobile phase with the aid of ultrasound for 30 minutes and dilute to 200ml with the mobile phase. Dilute 5ml of this solution to 50ml with the mobile phase and filter.
Reference solution: Dissolve a quantity of Citicoline sodium reference standard in the mobile phase to obtain a solution containing 0.005 per cent w/v of citicoline.
Chromatographic system:
- A stainless steel column 25cm X4.6mm, packed with octadecylsilane bonded to porous silica (5µm)
- Mobile phase: a mixture of 95 volumes of buffer solution prepared by dissolving 1.697g of tetrabutylammonium hydrogen sulphate in 1000ml of water, add 2ml of triethylamine and adjusted to pH 6.0 with dilute acetic acid and 5 volumes of methanol.
- Flow rate: 0.8ml per minute,
- Spectrophotometer set at 270nm,
- Injection volume: 20µl
Equilibrate the column with mobile phase for at least 90 minutes. Inject the reference solution. The test is not valid unless the column efficiency is not less than 3000 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 the reference solution and the test solution.
Calculate the content of Citicoline in the tablets.
Formula:
Area of Test STD Wt.(mg) 5 100 50 Potency
—————–X————–X——-X—————X——–X———–X Average wt.
Area of STD 200 50 Test Wt.(mg) 5 100
Alternative Method: By UV Spectrophotometer
Test Solution: Weigh and powder 20 tablets. Weight sample equivalent to 100mg of Citicoline 100ml volumetric flask add 20ml water into it and sonicate to dissolve the test sample. Make up to mark with water. Filter and dilute 1ml of this solution to 50ml in same solvent.
Reference Solution: Weigh 100mg of reference standard of Citicoline in 100ml of volumetric flask. Add 20ml water into it and sonicate to dissolve. Dilute 1ml of this solution to 50ml with water.
Check Absorbance of test as well as reference standard at about 270nm in UV Spectrophotometer.
Calculate the content of Citicoline 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: 90.0%-110.0%
11.0) 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
w/v: Weight/Volume
Abs. Absorbance
