Solids 8

Capsule

solid dosage form containing at least one API and/or inert substances enclosed in a small hard or soft shell

Typical capsule shell material

gelatin, cellulose polymers

Hard capsules

• consist of two prefabricated cylindrical sections, body and cap

• typically contain powders and granules

• come in a variety of sizes

Soft capsules (soft gel)

• consist of a continuous gelatin shell

• contain a semi-solid or liquid fill

• come in a variety of shapes

• shells are softened by addition of glycerol or sorbitol

How does the addition of glycerol or sorbitol assist with administration of capsules?

increases flexibility, improves ease of swallowing, and reduces shell fracture

How is gelatin produced?

through heating and denaturation of collagen

Where is HPMC derived from and when would we use it?

• derived from plants

• important for vegetarian/vegan patients

Hard capsule preparation

• develop and prepare formulation

• fill correct capsule shell size and seal

• clean and polish finished shell

Soft gel capsule preparation

single-step process using rotary (punching) method or seamless (dripping) method

What is the relationship between hard capsule volume and the size number?

↑volume, ↓size number

Rotary (punching) method for soft gel formation

• 2 film sheets are placed between 2 die rolls while injecting a liquid between two sheets

• dies perform pressured formation, sealing and cutting off capsules

Seamless (dripping) method for soft gel formation

• liquid is dropped from the inner section of a double concentric nozzle

• film liquid containing a gelling agent is dropped from the outer section

• round seamless capsules are formulated by interfacial tension