Kinetic Behavior and Interaction of Bacampicillin in Alginic Acid Solution at Neural pH Region

Abstract

Stabilization of bacampicillin (BAPC) in suspension was examined by the addition of alginic acid (Alg). BAPC formed a slightly water-soluble adduct (BAPC-Alg) with Alg, in wich BAPC and Alg were presumed to be linked by ionic bonding. However, the suspension of htis chemically stable adduct showed a similar lability to a suspension of BAPC alone; chemically very unstable particles of BAPC base were deposited in the suspension. In contrast, when BAPC-Alg adduct was suspended in 1.0% Alg colution at the same pH region, the precipitation of the particles of BAPC base were not observed. This stabilization is supposed to be due not only to the chemical stability of the adduct, but also to an inhibition of the deposition of an unstable BAPC base particles by Alg.