TABLET DEFECTS : TABLET DEFECTS K.V.RAMANA REDDY
Dept.Of Pharmaceutics FEATURES : FEATURES Tablets are solid dosage form playing key role often in first place among all over dosage forms.
They having more stability, reliability.
Easy to use, administer,and packaging.
Suitable to all controlled dosage forms.
Favors towards manufacturing and technology of others.
Prefers rough handling.
Maximum output in short period of time. : In tablet production technology various kinds of tablets are making continuously with different excipients in accordance with standard procedures by highly trained,skilled,technically qualified persons even though some times it may led to defects in making of tablets.
Most majority of defects takes due to various reasons. among those following were exists as close they include Related to one another, some times dependable also. Sources of Tablet Defects : Sources of Tablet Defects Moisture
High speed machines
Tools setting problem
Excess use of binders
Lack of proper lubricant selection Air interaction
Lack of knowledge
Abnormal ratio of excipients
Size, shape Slide 5: Black particle
Thickness variation fissured or pitted surface
Sticking &pickling Slide 6: Weight variation
Binding in die
Different color Slide 7: Chipped edge
Coat mottle STICKING : STICKING Always occurs in low melting point substances, and moisture supports this defects, lower the speed up of upper and lower punch leads to weight variation of tablets.
It produces rough and chipping surface tablets.
It develops material on both punches.
Lack of drying is basis of this one.
Selection of Binding agent is essential to solve sticking.
Ideal selection of lubricant in desired proportion will minimized this problem. PICKING : PICKING Material is is remove or picked up by upper punch from upper surface of tablet.
It favor initiation of sticking process, adhere strongly to tablet surface.
The similar charged particles present on excipients promotes picking.
If punches are having embossed or enground surface.
The conditions are affecting the rate of sticking same will affect picking also.
High input ie.dump or wet aggregates supports picking.
Use higraded dies and punches.
Avoid wet granules. MOTTLING : MOTTLING It associated with migration of coloring agents into surface of tablets.
The incorporation/addition of different excipients with dividing colors is main factor .
At high temperature dyes are easily migrate to surface and spread to upper surface.
The improper size either large or small particles enhances color distribution.
During preparation dyes are not properly mixed and not selected ideally or any incompatibility will tends to enhance appearance of color on tablet surface.
Improper storage conditions. CAPPING : CAPPING Continuously high speed of tablet machine and high degree of compression setting makes tablet to separate main surface into individual surface.
Avoid defective punches and dies.
High temperature adjustment also favor capping.
Distance between upper and lower punches will entrap air is bone factor for capping.
Fine particles were susceptible than coarse particles will affect ideality of tablets.
Capping minimized by keeping the feed material with cohesive nature. Slide 12: Overcome by adding adequate amount of binding agent.
Bond breaking is extended to maximum level among particles.
Use of large granules in small diameter dies produces bridging across die and uneven fill. WEIGHT VARIATION : WEIGHT VARIATION Improper blending of granules.
Lack of sufficient of lubricant .
Abnormal uniform mixing of all excipients.
Improper tool setting of machine.
Hi-speed running of machine.
improper glidant selection.
Abnormal size of granules.
Improper drying making tablet with different weight.
Heavy input in hooper. PRINT DEFECT : PRINT DEFECT It is mainly observed in tablets which having hard corners/designs on punches.
It takes due to improver punch cycle.
Punches having rough surface .
Improper blending of total powder.
Letter are designed with uneven surfaces on punches. HAIR/FIBRE : HAIR/FIBRE As name itself indicates some unwanted particles/hair are appeared on tablet surface.
Not following SOP.
Operator not implementing cGMP.
Lack of attention of operator.
Punches are cleaned before installing in their respective places.
Lack of cleaning/spacious rooms. BLACK SPOT/STAIN : BLACK SPOT/STAIN Stains or spots will be appear on tablet surface.
Migration of coloring agent upon storage.
High temperature is key factor for penetration of dye into upper surface.
Improper cleaning of punches.
Mainly observed in colored tablets.
Observe in high concentration of dyes.
Incompatibility among excipients and API LAMINATION : LAMINATION It is major problem among of all defects.
Occur upon storage period, or soon after compression.
Air entrapment between layers of tablet.
Low levels of binding agent.
It minimized by improving lubricant concentration.
Change the method of granulation.
By direct compression technique it is prevented to some extent.
Use always dry material (feed). CHIPPED EDGE : CHIPPED EDGE Tablets having sharp edge, elongated tablets are prone to chipped edge.
Granules are subject to high temperature will improve chipped surface (high drying).
This defects accompanied with damaged surfaces at its corners of tablet ,easily fragmented by even smooth handling also.
Due to rough handling.
Tablet shape is abnormal than normal.
Use optimum level of binding agent. SOFT TABLETS : SOFT TABLETS The tablets are susceptible to hydrolysis will develop soft nature.
Mainly observed in polymer/coated tablets.
Lack of drying will enhance the softness.
Granulation particles will completely free from moisture by keeping to drying condition properly.
Soft tablet will form initiate/basis for sticking or picking defects.
Use of lubricant that impart waxy nature.
Application of low compaction pressure.
The strength of bond is weakened across granules. PROTRACTED DISINTEGRATION : PROTRACTED DISINTEGRATION Disintegration time is extended in tablet.
Use of high compression on punches.
Incorporation of lubricant in excess quantity.
Overcome by using proper suitable surfactant concentration.
Addition of more concentration of binding agent.
Too low compression also favors extend disintegration time. Slide 21: THANK YOU