Synthesis, Characterization and Electrochemical Sensor Based Upon Novel Schiff Base Metal Complexes Derived from the Non-Steroidal Anti-inflammatory Drug, Flufenamic Acid for the Determination of Uric acid and their Biological Applications

The current trend in coordination chemistry is the design and synthesis of new Schiff base transition metal complexes for therapeutic, diagnostic, and catalytic applications. For decades, it has been observed that special attention is being paid to the chemistry of Schiff base metal complexes because of their wide range of applications. Therefore the present paper involves the synthesis of Schiff base ligand by altering the functional group of the drug, Flufenamic acid. From that Schiff base ligand, four complexes, i.e., Co(II), Cu(II), Ni(II), and Zn(II) have been prepared (SB metal complexes). The synthesized SB metal complexes have been characterized using several spectral and analytical techniques. All the metal complexes show non-electrolytic behavior suggested by molar conductance measurements. Spectral studies suggest that all four metal complexes exhibit octahedral geometry. The modified SB-Co complex/GCE showed a greater electro- catalytic activity and lower potential towards the oxidation of uric acid (UA). The response of UA was linear over the concentration ranging from CV is 0.5-1.8 mu mol/L, sensitivity for 131.85 mu A mu M(-1)cm(-2), and detection limit for 0.16 mu M (S/N=3). The modified GCE showed very good sensitivity along with good repeatability and reproducibility for the determination of UA. The pure drug, Schiff base ligand, and metal complexes, were also screened for anti-inflammatory and antibacterial activities. The observed results prove that the metal complexes exhibit greater activity than that of the original drug.