Calcium pectinate gel coated pellets as an alternative carrier to calcium pectinate beads

A conventional method of using drug entrapped in calcium pectinate beads as sustained release drug delivery systems have long been suffering from too rapid an in-vitro release. An approach to solve this setback by the method of calcium pectinate gel (CPG) coated pellets was then initiated. The spherical theophylline pellets, which contain calcium acetate, were prepared using an extrusion-spheronization method and then coated with pectin solution, using an interfacial complexation process. An insoluble and uniform coating of CPG was formed around the pellets. The comparison was made between theophylline uncoated pellets, calcium pectinate beads and this developed method by the variation of coating time and the type of pectin. The results in simulated gastric fluid (SGF) and water showed that theophylline release from the coated pellets was slower than that from the beads. The time for 50% release of theophylline (t(50)) from the CPG coated pellets in water and SGF are greater than the uncoated cores and the conventional beads. These results suggested that the coated pellets system were able to retard the release of theophylline to a greater extent than the conventional method. Therefore, this approach has been successfully achieved. (C) 1997 Elsevier Science B.V.