Physicochemical studies on Ciclopirox olamine complexes with divalent metal ions

Ciclopirox olamine (CPO) metal complexes have been prepared and characterized using elemental analysis, infra red (IR), melting point and differential scanning calorimetry (DSC). Spectroscopic titration using molar ratio method indicated the occurrence of 1:1 complexes for CPO with almost all the examined metals. Physicochemical properties were also studied including aqueous solubility and apparent partition coefficient. Results showed that generally complex formation dramatically decreased the solubility and increased apparent partition coefficient. However, some metal complexes exhibited opposite effect. It could be concluded that complex formation can modify the solubility and apparent partition coefficient, which may suggest the use of complexes to manipulate the physicochemical properties of the drug.