THE USE OF ALGINIC ACID AND ITS SALTS IN THE PHARMACEUTICAL FIELD

Sevgi TAKKA*, Füsun ACARTÜRK*°

*Gazi University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Etiler-Ankara, TURKEY
°Corresponding Author

Summary:
Alginic acid and its salts, alginates,are naturally hydrophilic colloidal polymers which are extracted from brown seaweed by Stanford in1880. Alginates can be considered as block polymers. The different parts are refferred to as M blocks, G blocks and MG blocks. One of the most useful properties of alginates is the the abillity to form gels. Addition of di or polyvalent cations (except Mg++) to alginate solutions causes gel formation by cross-linking.Calcium,barium or strontium can be used as crosslinking agents. Alginates has been widely used in food industry, textile processing, paper making, medicine, pharmaceutical technology applications and also most commonly used as dental impression material. Alginates have received much attention in pharmaceutical preparations, particularly as a vehicle for controlled drug delivery of gel beads.The effect of the various formulation factors on the properties of gel beads and the release rate of drug from alginate-gel beads have been investigated by several authors. Some additive polymers such as chitosan, polylysine and polyacrylic acid can be used to control the release of drug from the beads. Alginates are also used as a matrix material for the encapsulation of microbial cells, enzymes and islets of Langerhans.

Key words:
Alginic Acid, Alginate-Gel Beads, Controlled Drug Delivery