Supramolecular Analysis and Antimicrobial Properties of Bismuth-Based Coordination Polymers: Crystal Structure and Hirshfeld Surface Insights

Abstract

The eradication of diseases caused by microorganisms, including bacteria, viruses, and fungi, remains a major concern for human health. In this context, the development of novel materials and methodologies is essential for exploring potential growth inhibitory activities in both solid and liquid media. This study focuses on the synthesis and characterization of three bismuth-based coordination polymers (Bi-CPs) constructed from polycarboxylate ligands, with potential antibacterial and antifungal properties. The compounds were fully characterized using a combination of solid-state techniques, including powder X-ray diffraction, UV–Vis spectroscopy, scanning electron microscopy, thermal analysis (thermogravimetric analysis and differential calorimetry scanning), and Fourier-transform infrared spectroscopy, to establish their structural features prior to biological evaluation. To gain deeper insight into the intermolecular contacts and supramolecular packing, Hirshfeld surface and textural analysis and the corresponding fingerprint plots were performed. Their inhibitory effects were subsequently assessed in vitro against Staphylococcus aureus, Bacillus atrophaeus, and species of the Candida genus. Additionally, the minimum inhibitory concentration was determined, and their microbial growth profiles of two selected species were monitored over 24 h. Overall, these findings highlight the potential of these Bi-CPs as promising antimicrobial agents for applications in human health.