F. Soofivand
CNR,
Italy
Keywords: black phosphorous, 2D nanomaterials, biomedical application, antibacterial properties, curcumin
Summary:
Black phosphorus (bP), a promising two-dimensional (2D) material, has garnered significant attention due to its unique properties, particularly its size-dependent tunable band gap, which is crucial for a wide array of applications, from energy to biomedical fields [1]. In this study, we focused on optimizing bP nanostructures for their antibacterial properties and applicable potential in photodynamic therapy (PDT). Black phosphorous nanostructures were synthesized through a liquid-phase exfoliation technique using water as main solvent, chosen for its biocompatibility and health safety. The exfoliation process was optimized by varying key instrumental parameters including sonication time as well as experimental parameters like surfactant, solvent, and centrifugation speed, to achieve nanostructures with controlled size, stability, and enhanced reactive oxygen species (ROS) generation [2]. Our findings highlighted the importance of each parameter in the synthesis process (as shown in Fig. 1). Surfactant type was crucial for stabilizing the bP nanostructures, with charged surfactants providing better yield compared to other ones. The choice of solvent also played a key role [3], although using water proving to be the most suitable for biocompatible nanostructures, benefiting from a suitable co-solvent helped to decrease the surface tension of water and increase the exfoliation yield [4]. Additionally, the centrifugation speed was optimized to control the size distribution of bP, as the larger nanostructures with higher concentrations are resulted with lower rate, while decrease ROS amount and stability. So, optimization of this parameter to ensure the antibacterial performance and ROS production is necessary. Curcumin, a natural photosensitizer with known therapeutic properties [5], was conjugated to the bP to further enhance ROS generation for PDT applications. The integration of curcumin not only improved the exfoliation and stability of the bP suspension but also significantly boosted ROS production under light exposure. DPBF assays confirmed the increased singlet oxygen generation, as well as antibacterial tests demonstrated the effectiveness of the bP-curcumin system in inhibiting bacterial growth. Comprehensive characterization techniques, including UV-Vis spectroscopy, fluorescence spectroscopy, Raman spectroscopy, FT-IR, AFM, DLS, and SEM, validated the properties of the products. Finally, it is worth mentioning that the synergistic effect of bP and curcumin offers a promising, stable, and biocompatible platform for the development of advanced therapies. References: 1. Pharmaceutics 2023, 15(12), 2748 2. Nano Lett. 2020, 20, 3943 3. FlatChem. 2024, 45, 100665 4. Journal of Molecular Structure 2022, 1260, 132862 5. ACS Appl. Nano Mater. 2024, 7 (15), 17239