Experimental Spectroscopic Characterization and Biological Response of Cu(II) and Zn(II) Coordination Complexes: DNA Association, Plasmid Cleavage, and MCF-7 Cytotoxicity

This original experimental work examines a six-complex Cu(II)/Zn(II) coordination series through FTIR, Cu(II) EPR, DNA-association, thermal-denaturation, plasmid-topology and MCF-7 cell-assay measurements. Six numerical tables and eight plotted figures are evaluated together to test whether chemical coordination descriptors, DNA affinity, cleavage and cellular activity follow the same ranking. The examined DNA-binding constants are approximately 1.2–3.3 × 10⁵ M⁻¹, whereas plasmid nicking and MCF-7 IC₅₀ vary without a simple common ranking. A separately published Zn(II) Schiff -base antioxidant study is discussed as a literature comparator, not attributed to the six-complex experiment. Mechanistic hypotheses are distinguished from measured results. Full preparative protocols, raw instrumental files, replicate-level assay records and complete experimental-record metadata should be checked before submission.