In vitro study: green synthesis and evaluation of MgO/C-dots/DOX phosphorescent nanocomposites for photodynamic/photocatalytic therapy of tumors

Abstract

MgO nanoparticles (NPs) and carbon dots (C-dots) were synthesized by co-precipitation and hydrothermal techniques. In the next step, as-synthesized NPs were modified by C-dots. Then, polyethylene glycol (PEG) was conjugated with MgO/Cdots. Finally, Doxorubicin (Dox) as an anticancer drug was loaded on MgO/Cdots/PEG nanocomposites. The XRD pattern showed the characteristic peaks of C-dots and MgO. The FTIR spectrum showed that MgO/C-dots possessed the carboxyl functional groups, allowing DOX to be loaded onto MgO/C-dots/PEG through hydrogen bonds. The particle size of MgO, C-dots, MgO/C-dots, and MgO/C-dots/PEG/DOX was 20–30, 5–10, 30–40, and 100–130 nm, respectively, using TEM, DLS, and FESEM techniques. MgO, MgO/C-dots, and MgO/C-dots/DOX were fluorescent NPs when excited by a UV source. Anthracene and methylene blue were used as fluorescent probes to identify the reactive oxygen species (ROS) produced by UV excitation. The activity of MgO/C-dots and MgO/C-dots/DOX against colorectal cancer (C26) cells, after repeated 5-min illumination with both UV-light and red light LEDs, were measured by MTT assay. C26 cancer cells incubated with DOX-loaded MgO/C-dots and exposed to either wavelength (UV and red) killed ∼70% of cells. The green synthesized nanocomposites could act as anti-cancer photosensitizers probably by a photocatalytic mechanism.

Evaluation of Structural, Morphological, Optical and Bactericidal Action of Branched Sm‐Doped CuO Nano‐Lanceolates

“…Consequently, the surface of the bacterial strains leads to either inhibition of bacterial growth or killing of both bacterial cells. [12,13] Thus, it can be observed that SC1 has a higher level of bacterial deactivation than SC, SC2, and SC3. Furthermore, the surface morphology reveals that the Smdoped CuO nano-lanceolates annealed at the comparatively low temperature of 300 °C have outstanding antibacterial activity, with the lanceolate-like structure and widening band gap being important contributors.…”

“…[4] Few research findings also suggest that suitable photons of the proper wavelength are used to illuminate the nanoparticles which contribute to the enhanced antibacterial activity because of the production of reactive oxygen species (ROS), mostly hydroxyl radicals of H 2 O 2 and singlet oxygen. [11][12][13] Moreover, because of their distinctive optical characteristics, rare earth elements are frequently selected as prospective dopants for antibacterial examination. Researchers have recently become intrigued about trivalent rare earth ions (Tb 3 + , Er 3 + , Ce 3 + , Dy 3 + , Tm 3 + , and Sm 3 + ) doped with metal oxides [14][15][16][17] due to their numerous applications which include photocatalysis, [17] optoelectronics, [14] PEC energy devices, [16] and antibacterial activities.…”