Lanthanum metal complexes were synthesized using a classical condensation method by reacting lanthanum nitrate salts with a bidentate ligand in a 1:2:1 molar ratio (M:L:L). The formation and structure of the resulting complexes were confirmed through a combination of analytical techniques, including Fourier transformation infrared spectroscopy, thermal gravimetric analysis, X-ray diffraction, elemental microanalysis, and scanning electron microscopy. The lanthanum complexes synthesized exhibited strong in vitro antimicrobial activity. Antibacterial screening showed inhibition zones of 18–26 mm against Staphylococcus aureus and Escherichia coli, surpassing those of the reference drug ciprofloxacin (16–20 mm). Antifungal studies demonstrated inhibition zones of 15–23 mm against Candida albicans and Aspergillus niger. The MIC values ranged from 25 to 50 μg/mL, indicating high potency. Additionally, moderate antimalarial activity was observed against Plasmodium falciparum (IC50 = 12.4 μM). These findings confirm that lanthanum complexes possess potent antibacterial and antifungal properties, highlighting their promise as potential candidates for novel antimicrobial and antimalarial drug development.
KADAM et al. (Wed,) studied this question.