New spectrophotometric techniques were introduced for the determination of Fe(III) and Cu(II) in many different analyzed samples. The concentrations of Fe(III) and Cu(II) ions were measured in the existence of a novel Schiff base (Z)-6-(3-mercapto-5-methyl-4H-1,2,4-triazol-4-ylimino)-2-thioxotetrahydropyrimidin-4(1H)-one (MMTP). The new chelates were formed rapidly at the room temperature at 510 and 550 nm in presence of triton X-100 and CPB surfactants for Fe(III) and Cu(II), respectively. Linear calibrated graphs were obtained at concentration ranges of 1.0–130 µg mL-1 for Fe(III) and 0.5–90 µg mL-1 for Cu(II). LOD were calculated to be 1.05, 1.98 µg mL-1 and LOQ were 3.18 and 6.02 µg mL-1 for Fe(III) and Cu(II), respectively. A large number of foreign ions were not interfering in the present method. The stoichiometric composition of the chelates was studied by molar ratio and job´s methods to be found 1:2 (metal ion: ligand) ratio. The Fe(III) and Cu(II) solid chelates were prepared and characterized using IR, UV–Vis., 1 HNMR , 13CNMR TG-DTG, and XRD spectroscopy. The IR spectral revealed that MMTP chelated as a bidentate ligand via NO atoms. Thermal analysis revealed the decomposition mechanism of MMTP and its chelates. A suggested octahedral geometry encompasses all of the chelates. The UV–visible spectra and magnetic moment analyses confirm the octahedral geometrical geometries. The band gap (Eg) values are 1.53 and 1.56 for Fe(III) and Cu(II) respectively. The smallest band gaps imply that these chelates are semiconductors belonging to solar materials. The in-vitro antioxidant activity of the individual chelates was evaluated using the DPPH radical scavenging assay. All compounds showed antioxidant activity with IC50 values of 0.316, 0.186 and 0.124 mg/mL for MMTP, Fe(III) and Cu(II), respectively. MMTP and its chelates were tested for their antimicrobial activity against various types of bacteria and fungi using the disc diffusion method. The Cu(II) complex showed the greatest biological activity.