Structural, Vibrational, Thermal, and Cytotoxic Characterization of Aqua(1,10-Phenanthroline)(L-Serinato)Copper(II) Nitrate Complex Combined with DFT Calculations

Abstract

In this study, X-ray diffraction confirms the crystallization of aqua(1,10-phenanthroline)(L-serinato)copper(II) nitrate in the triclinic system (P-1). Density functional theory calculations are used to assign the vibration bands of Cu²⁺ ion and phenanthroline (phen) and L-serine (L-ser) ligands obtained by Raman and Fourier-transform infrared spectroscopy. Physical and analytical properties, evaluated by computational study utilizing CrystalExplorer software, show the prevalence of H···O/O···H interaction. Thermal analyses show that the complex is stable in the temperature interval of 300–390 K. For temperatures above 390 K, the elimination of coordinated water molecules (380–430 K), mass loss of serine (440–660 K), and material decomposition process above 660 K. The solubility of the complex in water reaches 21.4 mg mL⁻¹ at 35 °C. Parameters of drug-likeness and assessment of absorption, distribution, metabolism, and excretion (ADME) properties are calculated. The in vitro cytotoxic assays against the cancer cell line of the HCT-116 type (human colorectal carcinoma) exhibits toxicity (IC₅₀ = 1.88 µm and selectivity index of 2.17) for the complex. The results highlight the potential of ternary copper complexes such as [Cu(phen)(L-ser)(H₂O)]NO₃ for anticancer drug development as attractive, efficient, and low-cost materials.