An Oxygen-Self-Produced Nanoplatform Based on MnO2 for Relieving Hypoxia

Manganese dioxide (MnO₂) nanoparticles are increasingly recognized for their potential in biomedical applications, particularly in the realm of hypoxic cancer therapy, due to their unique physicochemical characteristics. This investigation introduces a novel, template-free synthesis strategy. The reducing groups inherent in bovine serum albumin (BSA) facilitate a redox reaction with potassium permanganate (KMnO₄), while the abundance of functional groups in BSA is instrumental in the formation of MnO₂. The transmission electron microscopy (TEM) analysis has characterized the synthesized MnO₂ nanoparticles, termed BM NPs, as spherical particles with a mean diameter of 210 nm and zeta potential of −40.1 mV measured by dynamic light scattering (DLS). The Fourier transform infrared (FT-IR) spectrum of BM NPs exhibits the characteristic peak of MnO₂ at 1113 cm⁻¹ and 620 cm⁻¹_. Furthermore, the elemental composition of BM NPs has been ascertained through energy-dispersive X-ray (EDX) elemental mapping analysis. Though concentration of BM NPs up to 200 μg/mL, the survival rate of 4T1 cells remained approximately 75 %. Given that BM NPs at a concentration of 100 μg/mL significantly alleviate cellular hypoxia, the high oxygen-generating capacity of these nanoparticles is proved, suggesting their suitability as a drug delivery system, especially in the context of hypoxic tumor microenvironments.