Capsule

• Capsule Definition
• Capsule Advantage / Dis Advantage
• Type of Capsule
• Capsule Size

DEFINITION:-
Capsule are solid dosage forms in which the active medicament are enclosed in either a hard or soft soluble container or shell of a suitable form of gelatin.
OR
Capsules are solid dosage forms in which drug and/or inert substances are enclosed in a gelatin shell. The gelatin shell may be hard or soft depending on their composition.
The word capsule is derived from the latin capsula, meaning a small box.

ADVANTAGE :-

• They obscure the taste and odour of unpleasant drug.
• They are attractive in appearance.
• They are slippery when moist and hence, easy to swallow with a draught of water.
• If properly stored the shells contain 12-15% of moisture which give flexibility and consequently very considerable resistance to mechanical stresses.
• Less adjuncts are necessary than tablets.
• The contents are usually in fine powder which combined with adjuncts provides rapid and uniform release of medicament in the GIT.
• The shells can be opacified with Tio2 or coloured to give protection from light.
• The shells are physiologically inert and easily and quickly digested in the GIT.
• Presentation of a drug in capsule rather than in tablets, allows quicker submission of a new drug for clinical trial because fewer development problem are involved. Also it is easier to vary the dose.

Dis advantage of capsule dosage form

• Capsule are not suitable for liquids that dissolve gelatin. Such as aqueous or hydroalcoholic solution.
• The concentrated solutions which required previous dilution are unsuitable for capsules because if administered as such lead to irritation into stomach.
• Not useful for efflorescent or deliquescent materials. Efflorescent cause capsules to soften & deliquescent may dry the capsule shell to brittleness.

Gelatin
Gelatin is a heterogenous product derived by irreversible hydrolytic extraction of treated animal collagen obtained from animal connective tissue/bone/skin.
Type of gelatin
TYPE A :- Gelatin is derived mainly from poke skin by acid treatment. This gelatin has an isoelectric point in the region of pH 9.
TYPE B :- Gelatin is derived from bones and animal skins by alkaline processing.(pH 4-5)

MANUFACTURE OF GELATIN :-

TYPE B  dry bone → 5 % HCl, 10-15 days → lime 10% 4-8 week → lime removal → pH adjacent → hot water → filter →  vacuum concentration → cool to solidify →  air dry → mill to size 

TYPE A pork skin → wash → acid 1-5% HCl 10-30hrs → acid removal → hot water → filter → vacuum concentration → cool to solidify →  air dry → mill to size.
Gelatin possesses five basic properties that make it suitable for the manufacture of capsules :-
It is non-toxic, widely used in foodstuffs and acceptable for use worldwide.
It is readily soluble in biological fluids at body temperature.
It is good film – forming material producing a strong flexible film. The wall thickness of a hard gelatin capsule is about 100 µm.

Solution of high concentration 40% w/v are mobile at 50?. Other biological polymer such as agar are not.

Bloom or gel strength :- a measure of the cohesive strength. Of cross linking that occurs between gelatin molecule & is proportional to the M.W. of the gelatin higher the bloom strength more physically stable the capsule shell. Bloom range is 150-250 g.

TYPE OF CAPSULE
HARD GELATIN CAPSULE
SOFT GELATIN CAPSULE
MICROCAPSULE
HARD GELATIN CAPSULE :-

MANUFACTURE OF EMPTY HARD GELATIN CAPSULE :-
GELATIN SOLUTION :-  Once raw material have been received and released by quality control the gelatin and hot demineralized water are mixed under vaccum in stainless gelatin melting system.
From receiving tanks the gelatin solution is transferred to stainless steel feed tanks.
Dyes, opacifants, and any needed water are added to the gelatin in the feed tanks, to complete the gelatin preparation procedure.
From the feed tank, the gelatin is gravity fed to dipper section.
Dipping :- pairs of stainless steel pins are dipped into the dipping solution to forms cap and bodies. The dipping solutions is maintained at the temp. about 50? in heated lacked dipping pan.
Spinning :- The pins are rotated to distribute the gelatin over the pins uniformly & to avoid the formation of head at the capsule ends.
Drying :- The gelatin is dried at the blast of cool air to form the hard shell. The pins are moved through the series of air drying kilns to remove the water.
Stripping :- The series of bronze jaws & strip the cap & body portion of the capsule from the pins.
Trimming & joining :- The stripped cap & body portion are trimmed to the required length by stationary knives.
Polishing :-  pan polishing :-  acela-cota pan is used to dust & polish.
Cloth dusting :-capsule are rubbed  with the cloth. Brushing :-capsules are filled under the soft rotating brush.

HARD CAPSULE SIZE