Kinetics and Mechanism of Interaction of cis-Diaquabis(oxalato)chromate(III) with Cefoperazone in Aqueous Medium: as an Antibacterial Study

Purpose Chromium species in higher oxidation states are toxic and carcinogenic. But lower oxidation state as Cr(III) microelement shows potential antimicrobial properties. Cefoperazone sodium is a parenteral bactericidal third-generation cephalosporin antibiotic effective in treating Pseudomonas bacterial infections. A new drug formed with the complexation of metal and drug. Hence, newer coordinated drugs were explored that can also show the antimicrobial effectiveness similar to free drug. Methods cis-[Cr(C2O4)(2)(H2O)(2)](-) was synthesized by the proposed method and its complexation with cefoperazone was done by reflux for 5-6 h with stirring. The structure was characterized by spectroscopic techniques (UV, IR, mass, and AAS). The antimicrobial study was done using agar disk-diffusion method. The interaction of the ligand substitution reaction between cis-[Cr(C2O4)(2)(H2O)(2)](-) and cefoperazone (CFZ) has been investigated in aqueous medium. The reaction has been found to proceed by depending on ligand concentration. Results The kinetic reaction was studied at [CFZ] varied from 1.50 x 10(-2) mol dm(-3) to 4.50 x 10(-2) mol dm(-3) with pH variation from 3.0 to 5.0. The rate of reaction is found to increase in [H+] and [CFZ]. The activation parameters Delta H-# and Delta S-# are found to be 42.72 kJ mol(-1) and - 182.41 J K-1 mol(-1) respectively. The positive values of activation enthalpy (Delta H-#) shows that the decomposition process is endothermic. Conclusion Compared to the free cefoperazone, complexation with chromium(III) metal ion shows similar antimicrobial activity. The reaction takes place through an associative interchange mechanism.