Coating of tablets- film coating of tables/granules
Aim: To perform coating of granules.
Granulation is a technique of particle enlargement by agglomeration, is one of the significant unit operations in the production of pharmaceutical dosage forms, mostly and capsules. During the granulation process, small fine or coarse particles are convened into large agglomerates called granules.
Generally, granulation commences after initial dry mixing of the necessary powder ingredients along with the active pharmaceutical ingredient so that a uniform distribution of each ingredient throughout the powder mixture is achieved.
|Ingredients||Qty Given||Qty Taken|
|Hydroxy propyl methyl cellulose||4%|
|Methylene chloride||q.s. ad 100%|
- Preparation of Coating Solution: Add the polymer gradually to the ethyl alcohol and agitate the solvent with continuous stirring.
- Add the some portion of methylene chloride to this suspension so that polymer gets solubilized.
- Add the propylene glycol and remainder of methylene chloride to the above solution under constant stirring and the final mixture is mixed well by continuous stirring for 15-20 min.
- Filter the prepared coating solution.
Granules Coating Operation:
- Place 200 g of plain granules in the coating pan with three pieces of baffles installed.
- The plain granules are heated to 4040°C by applying hot air.
- Adjust the air pressure and the spraying speed of the spray gun to produce properly atomized coating liquid.
- Turn on the coating pan and change the rotation speed to 20 rpm.
- Spray the coating liquid onto the granules until a uniform film coating is formed.
- Keep the distance of 25 inches of coating from the granule bed for efficient coating.
- Stop spraying and keep the coating pan running for an additional few minutes to avoid sticking between the coated granules.
- The granules were dried after coating by blowing air.
Observations of film coated granules
|Dark marks||Uniform/Non uniform||Passes/Fail|
Precautions While Coating:
- During the coating process, the selection of the spraying rate of the coating liquid and the air blowing speed should be made with the aim not to over-wet the granules and to prevent sticking.
- The temperature should not be too high or too low. If the temperature is too high. the coating film formed will not be uniform; on the other hand, if the temperature is too low, drying will be very slow and the coated granules may stick to each other.
- Air bubbles should be avoided during the coating process.
- The coating materials should be passed through a 150-200-mesh sieve if particle agglomeration is present (or homogenized by using a homogenizer).
Results: Plain granules are uniformly film coated and submitted.
Industrial Pharmacy I Practical
- Preformulation studies on paracetamol/aspirin/or any other drug
- Preparation and evaluation of Paracetamol tablets
- Preparation and evaluation of Aspirin tablets
- Coating of tablets- film coating of tables/granules
- Preparation and evaluation of Tetracycline capsules
- Preparation of Calcium Gluconate injection
- Preparation of Ascorbic Acid injection
- Quality control test of (as per IP) marketed tablets and capsules
- Preparation of Eye drops/ and Eye ointments
- Preparation of Creams (cold / vanishing cream)
- Evaluation of Glass containers (as per IP)
Third Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise