Effect of metal in Schiff bases of chitosan adsorbed on glassy carbon electrode in the inhibition of sphingomyelinase C toxin

This study was conducted to assess the catalytic electrode surface adsorption and capture properties of different metal chitosan derivatives in aqueous phosphate buffer solution (pH = 7.3). Early, recent work showed that the response of Iron chitosan complex with R = -CH3 on the periphery, over blood red cells in presence of sphingomyelinase C was protected. The effect of others substituent (R = -Br, -Cl, -F, NO2, -OCH3, -H) on the periphery of the Schiff base ligand did not show correlation with the oxidation of sphingomyelinase C and its biological response. For this reason, various adsorbed metal (M = Fe of recent work, Cu, Ni and Co) complexes of chitosan and Schiff bases on glassy carbon electrode for the oxidation of sphingomyelinase C were investigated and compared, each one with -CH3 group on the periphery of the Schiff base. UV–Vis and IR-TF spectroscopies, electrochemistry and microscopy assay were performed; then, the metal effect underlying. For the Schiff base, cobalt and copper complexes did not proved to be a remarkable cellular protector in presence of the enzyme, but the nickel complex showed to be a cellular protector at short time, this conclusion help to proposal a reaction mechanism for the electrochemical and biological studies. •The inhibition of Sphingomyelinase C by metal chitosan complexes was examined.•Metal chitosan complexes were active for the oxidation of SMASE.•NiChi-CH3 protected to erythrocytes exposed to Sphingomyelinase C at short times.•Reactions for SMASE oxidation by MChi-CH3 were proposed.