[Natural polymers in the formulation of hydrophilic matrix tablets]

Semisynthetic and synthetic polymers have found their use in the technology of hydrophilic matrix systems with controlled release of the active ingredient, in particular in oral administration. In the recent period, there is increased interest also in natural polymeric substances, whose advantage consists in safety, easy availability, and a relatively low price. They thus represent an interesting possibility to extend the selection of novel constitutive auxiliary substances. The present review paper surveys the most important natural polymers: alginans, carageens, Arabic gum, pectins, galactomanans, ispaghul, and xantan gum as potential carriers for oral hydrophilic systems with controlled release of active ingredients and describes its origin, properties, and possible uses in pharmacy.