Study on the aggregation of teicoplanin.

The aggregation of teicoplanin was studied in four solutions: 0.06 M phosphate buffers pH 4.3 and 6.3, both with and without 10% (v/v) of acetonitrile. Conductometry, capillary electrophoresis, cyclic voltammetry, and static light scattering were employed to determine the critical micelle concentration (CMC) of teicoplanin. Dynamic light scattering was used to give an additional information on the size and the size distribution of the particles formed. While the CMC was found in solutions without acetonitrile, attempts to detect any CMC failed in solutions containing acetonitrile. The results point out to different solvating mechanism in solutions with and without acetonitrile, leading to two different schemes of association.