Aim: Preparation and Evaluation of Aspirin Tablets

References

1. Aulton, M.E., & Taylor, K. (2017). Aulton’s Pharmaceutics: The Design and Manufacture of Medicines. Elsevier Health Sciences.

2. Indian Pharmacopoeia Commission (2022). Indian Pharmacopoeia.

3. Lachman, L., Lieberman, H.A., & Kanig, J.L. (2009). The Theory and Practice of Industrial Pharmacy. CBS Publishers.

Objective

To prepare Aspirin tablets using the wet granulation method and evaluate the tablets for various quality parameters such as hardness, friability, weight variation, disintegration time, and dissolution profile.

Materials Required

Active Pharmaceutical Ingredient (API): Aspirin (Acetylsalicylic Acid)

Excipients: Lactose (Diluent), Microcrystalline Cellulose (Binder), Corn Starch (Disintegrant), Magnesium Stearate (Lubricant), Talc (Glidant)

Solvents: Purified Water

Equipment Required: Analytical balance, Mortar and pestle, Tablet compression machine, Hardness tester, Friabilator, Disintegration test apparatus, Dissolution test apparatus, Sieves, Oven

Quantities of Ingredients (for 100 Tablets)

Aspirin: 325 mg per tablet x 100 = 32.5 g

Lactose: 120 mg per tablet x 100 = 12 g

Microcrystalline Cellulose: 20 mg per tablet x 100 = 2 g

Corn Starch (for Paste): 10 mg per tablet x 100 = 1 g

Magnesium Stearate: 5 mg per tablet x 100 = 0.5 g

Talc: 5 mg per tablet x 100 = 0.5 g

Purified Water: q.s. (quantum satis) to form a paste for granulation

 Procedure

1. Weighing of Ingredients: Accurately weigh 32.5 g of Aspirin, 12 g of lactose, 2 g of microcrystalline cellulose, 1 g of corn starch, 0.5 g of magnesium stearate, and 0.5 g of talc using an analytical balance.

2. Granulation:

• Mix Aspirin, lactose, and microcrystalline cellulose thoroughly in a mortar to ensure uniform distribution.
• Prepare a corn starch paste by dispersing 1 g of starch in a small amount of purified water and heating it until a smooth paste forms.
• Gradually add the starch paste to the dry powder mixture while stirring continuously to form a cohesive wet mass.
• Pass the wet mass through a sieve (No. 10 or 12) to form uniform granules.
• Dry the granules in an oven at 60-70°C until a constant weight is achieved.

3. Mixing:

• After drying, pass the granules through a sieve (No. 20) to break any large aggregates.
• Mix the granules thoroughly with magnesium stearate and talc to ensure proper lubrication and flow properties.

4. Compression: Compress the granules into tablets using a tablet compression machine. Each tablet should weigh approximately 485 mg (325 mg Aspirin + 160 mg excipients).

5. Evaluation of Tablets: Perform the following tests to evaluate the quality of the tablets:

   a. Weight Variation Test:

• Weigh 20 tablets individually and calculate the average weight.
• Ensure that no more than two tablets deviate by more than 5% from the average weight and none deviate by more than 10%.

   b. Hardness Test:

• Measure the hardness of 10 tablets using a hardness tester.
• The hardness should be within the range of 4-7 kg/cm².

   c. Friability Test:

• Weigh 10 tablets and place them in a friabilator.
• Rotate the friabilator at 25 rpm for 4 minutes.
• Reweigh the tablets and calculate the percentage weight loss.
• The friability should not exceed 1%.

   d. Disintegration Test:

• Place six tablets in the disintegration test apparatus.
• Record the time taken for the tablets to disintegrate completely.
• The disintegration time should be less than 15 minutes for uncoated tablets.

   e. Dissolution Test:

• Perform the dissolution test using a phosphate buffer (pH 4.5) at 37°C in a dissolution apparatus.
• Withdraw samples at regular intervals (5, 10, 15, 30, 45, and 60 minutes) and measure the absorbance using a UV spectrophotometer at 265 nm.
• Calculate the percentage of drug release.

 Calculations

1. Weight Variation:

Percentage Deviation =

2. Friability:

Percentage Friability =

3. Dissolution Profile:

 Calculate the percentage drug release at each time point using the standard calibration curve of Aspirin.

Sample Data Table

 Conclusion

The prepared Aspirin tablets meet the required quality specifications for weight variation, hardness, friability, disintegration time, and dissolution profile. The tablets are deemed suitable for further studies or therapeutic use.