Synthesis and evaluation of sodium alginate/borate glass–copper oxide nanocomposite films for dual antimicrobial and anti-osteosarcoma applications

Abstract

Developing multifunctional biomaterials for treating tumours and preventing infections remains a major clinical challenge. This study presents the synthesis and evaluation of sodium alginate (SA) composite films incorporating borate glass (BG) and copper oxide (CuO) nanoparticles (S1–S5). FTIR analysis confirmed successful BG-alginate condensation and Cu2+-carboxylate coordination, evidenced by the attenuation of the O–H band (∼3300 cm−1) and new C–O–B/C–O–C modes (1300–1200 cm−1). XRD results revealed a progressive structural evolution from amorphous (S1) to semi-crystalline (S5), with the crystallinity index increasing from 14% to 28.2%. UV-vis's spectroscopy showed material stability and tunable optical band gaps (2.8–3.7 eV). SEM-EDX showed copper-rich particulate surfaces (11.1% in S5). Biological assays demonstrated a non-linear composition–activity relationship. Sample S2 (1% CuO, 4% BG) exhibited exceptional in vitro anticancer potency against a human osteosarcoma cell line (MG-63) with IC50 ≈ 3 µg mL−1. Sample S5 exhibited superior antibacterial activity, yielding a 29 mm inhibition zone against P. aeruginosa outperforming clindamycin with broad-spectrum MIC values of 62.5 µg mL−1 for P. aeruginosa and 125 µg mL−1 for S. aureus. These findings establish SA/BG–CuO films as multifunctional biomaterials for osteosarcoma therapy and infection control.