Biocompatible Sodium Alginate Modified <scp>BaO</scp> ₂ H ₂ O ₂ Nanoparticles With Improved Therapeutic Efficacy Against Multidrug‐Resistant Pathogens and Cancer Cells

ABSTRACT The increasing problem of multidrug‐resistant pathogens and the limitations of conventional therapies for cancer treatments require designing new therapeutic agents. BaO 2 H 2 O 2 and BaSA nanoparticles were prepared and characterized to determine their antimicrobial, antifungal, and anticancer activities. The XRD confirmed the crystallite sizes to be 34 nm for BaO 2 H 2 O 2 and 25 nm for BaSA. The UV–visible analysis confirmed the band gap energies as 4.13 and 4.11 eV for BaO 2 H 2 O 2 and BaSA, respectively. A shift in the blue‐green PL emission from 488–510 nm in BaO 2 H 2 O 2 to 535 nm in BaSA indicated increased oxygen vacancies. EDAX analysis demonstrated elemental variations due to SA modification, whereas DLS measurements showed a decrease in the mean size of the nanoparticles from 116.70 nm (BaO 2 H 2 O 2 ) to 111.90 nm (BaSA). Antimicrobial activity was shown against Klebsiella pneumoniae , Shigella dysenteriae , Escherichia coli , Pseudomonas aeruginosa , and Proteus vulgaris , while a considerable enhancement of antifungal activity against Candida albicans was observed in BaSA. Against MG‐63 osteosarcoma cells, BaSA exhibited lower IC 50 values (21.5, 20.2, 18.7 μg mL −1 at 24, 48, and 72 h) when compared with BaO 2 H 2 O 2 (23.4, 22.5, 21.3 μg mL −1 ). Zebrafish embryos tolerated BaSA at 0.5 mg mL −1 , with developmental abnormalities observed only at 1.0 mg mL −1 .