Manuf (Capsule defects)

• Capsules are solid dosage forms in which medicine or a combination of drugs, with or without excipients, is enclosed in Hard Gelatin Capsule Shells, soft, soluble gelatin shells, or hard or soft shells of any other acceptable material, in a variety of shapes and capacities.
• Capsule Defects and Remedies are provided below to remove such types of defects.
• Loss of cap during transfer or misalignment of cap and body bush can be caused by high vacuum and can be remedied by reducing vacuum but making sure that it is not so low that capsule separation is not observed.
• Dents and pinholes (on tips) can be caused by excess closing/lock length setting during the encapsulation process, excessive lock length, excessive closing pressure, over-filling of capsules, incorrect pin size or pin configuration, and improper storage conditions (moisture).
• Cracks in Capsules can be caused by improper (storage) conditions favoring the transfer of moisture from the capsule shell to encapsulated components.
• Misalignment of the upper and lower capsule segments and incorrect setting of the cap hold-down pin in the joining station can cause telescopic Capsules.
• Wear of capsule closing units rubber sheet specifically at the point where the capsule strikes the sheet would lead to telescopic replacement if required
• Filling dusty fillings can be remedied by using a capsule polisher.
• Empty capsules can be caused by a malfunction in the capsule filling machine which is preventing empty capsules from reaching the exit chute.
• Capsule non-separation can be caused by insufficient vacuum or incorrect vacuum pump.
• Target weight not achieved can be caused by incorrect target weight with respect to selected capsule size and poor flow of product.
• Weight variation can be caused by wrong selection of dosing disc thickness, incorrect gap between dosing disc and supporting pad, tamping pin and body bush, dosing disc and wiper block, and dosing disc and body bush.
• Capsule lock length variation can be caused by excess joined length, improper setting of the closing plate, damage to the rubber sheet of the closing plate, and incorrect setting of the closing plate.
• Dusty Capsules can be caused by improper storage conditions (moisture).
• Empty Capsules can be caused by improper storage conditions (moisture).
• Damaged band can be caused by improper storage conditions (moisture).
• The capsule does not enter the rectifier block can be caused by improper storage conditions (moisture).
• Capsule getting damaged during loading can be caused by improper storage conditions (moisture).
• Capsule non-separation can be caused by improper storage conditions (moisture).
• Target weight not achieved can be caused by improper storage conditions (moisture).
• Weight variation can be caused by improper storage conditions (moisture).
• Capsule lock length variation can be caused by improper storage conditions (moisture).
• An ideal tablet should be free from any visual defect or functional defect.
• The advancements and innovations in tablet manufacture have not decreased the problems, often encountered in the production, instead have increased the problems, mainly because of the complexities of tablet presses; and/or the greater demands of quality.
• An industrial pharmacist usually encounters number of problems during manufacturing.
• Majority of visual defects are due to inadequate fines or inadequate moisture in the granules ready for compression or due to faulty machine setting.
• Functional defects are due to faulty formulation.
• Solving many of the manufacturing problems requires an in-depth knowledge of granulation processing and tablet presses, and is acquired only through an exhaustive study and a rich experience.
• The imperfections found in tablets are known as 'Visual Defects' and they are either related to imperfections in any one or more of the factors.
• Tablet processing problems can be due to the problem in the formulation or in the compression equipment, or both of them.
• A coloured drug is used along with colourless or white-coloured excipients.
• A dye migrates to the surface of granulation while drying.
• Improperly mixed dye, especially during 'Direct Compression', can cause problems.
• Improper mixing of a coloured binder solution can lead to problems.
• Use appropriate colourants to avoid problems.
• Change the solvent system, change the binder, reduce drying temperature and use a smaller particle size to remedy problems.
• Mix properly and reduce size if the particle size is larger to prevent segregation.
• Incorporate dry colour additive during powder blending step, then add fine powdered adhesives such as acacia and tragacanth and mix well and finally add granulating liquid to remedy problems.
• Double Impression involves only those punches, which have a monogram or other engraving on them.
• The tablet weights are mainly affected by product variation, machine condition, tooling condition, and powder flow and feed-rates.