Pharma gyan Pandit

Ideal properties of superdisintegrants

Superdisintegrant is used as an excipient in the tablet formulation, it has to meet certain criteria other than its swelling properties. The ideal disintegrants should have following properties:

1.      Poor solubility

2.      Poor gel formation

3.      Good hydration capacity

4.      Good moulding and flow properties

5.      No tendency to form complexes with the drugs

6.      Good mouth feel.

7.      It should also be compatible with the other excipients and have desirable tableting properties.

Different commonly used superdisintagrants are:

Modified Starches- Sodium Carboxymethyl Starch (Chemically treated Potato Starch) i.e. Sodium Starch Glycolate (Explotab, Primogel). Mechanism of Action: Rapid and extensive swelling with minimal gelling. Effective Concentration  is 4-6%. Above 8%, disintegration times may actually increase due to gelling and its subsequent viscosity producing effects.

Cross-linked polyvinylpyrrolidone- water insoluble and strongly hydrophilic. i.e. crospovidone (Polyplasdone XL, Kollidon CL) Mechanism of Action: Water wicking, swelling and possibly some deformation recovery. Effective Concentration is 2-4%.

 Modified Cellulose- Internally cross-linked form of Sodium carboxymethyl cellulose. i.e. Ac-Di-Sol (Accelerates Dissolution), Nymcel Mechanism of Action: Wicking due to fibrous structure, swelling with minimal gelling. Effective Concentrations is 1-3% (Direct Compression) & 2-4% (Wet Granulation).