Crystal structure, DFT-guided design, and selective antibacterial activity of a calcium-based hybrid for spray coating applications

Abstract

We report the synthesis and comprehensive characterization of a calcium-based organic-inorganic hybrid material derived from ethylenediaminetetraacetic acid (EDTA), a polyaminocarboxylate ligand, specifically designed to harness weak coordination interactions for antimicrobial and surface coating applications. Structural and spectroscopic analyses including single-crystal X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and thermal studies, including Differential Scanning Calorimetry (DSC) revealed a supramolecular framework stabilized by extended weak contacts between calcium and ethylenediaminetetraacetic acid (EDTA) moieties. Hirshfeld surface analysis confirmed the prevalence of non-covalent interactions such as hydrogen bonding and electrostatic forces, while density functional theory (DFT) calculations provided detailed insights into the electronic structure, orbital distribution, and charge localization. coccus haemolyticus (Gram-positive) than Escherichia coli (Gram-negative), a behavior attributed to calciummediated interactions with bacterial membranes. Upon deposition via physical spray coating onto glass substrates, the hybrid retained its supramolecular integrity and bioactivity, while exhibiting favorable surface wettability and adhesion characteristics. These findings highlight the strategic potential of EDTA-derived calcium hybrids in tuning physicochemical and biological functionalities through weak coordination chemistry. This integrated experimental-computational approach offers a versatile platform for the development of next-generation antimicrobial coatings applicable to biomedical surfaces and protective industrial materials