A Study of the Effects of Sucrose Concentration,Lacquer Concentration and Coating Time on the Formulation of Stable and Effective Carbenicillin Indanyl Sodium Microcapsules

Abstract

Carbenicillin indanyl sodium, commonly known as Geocillin (GC), is an orally effective derivative of carbenicillin employed in the treatment of gram negative infections of the urinary tract. GC exhibits an extremely bitter taste which affects patient compliance upon oral dosing (1). A novel coating approach allows Geocillin to be prepared as a suspension for oral administration. GC is available only as a tablet.

Eudragit E100^R [EE] is a tasteless, acid soluble cationic polymer. Encapsulation of GC with [EE] inhibited its release in the mouth, thus overcoming its bitter taste. Dissolution studies were carried out in simulated gastric fluid and simulated intestinal fluid. Three factors, viz. sucrose concentration, lacquer concentration and coating time were evaluated to arrive at an optimally acceptable formulation.

The formulation containing GC and sucrose in the ratio of 1:3, suspension coated using a 5% w/w lacquer solution for 40 mins. yielded taste free microcapsules with optimal release characteristics.