Carbon Dot Assemblies for Enhanced Cellular Uptake and Photothermal Therapy In Vitro

Abstract

Constructing complex nanoarchitectures via self-assembly with nanoparticle building blocks is a practical strategy that produces nanostructures with properties that are absent in the individual unit. In this work, we used hydrophilic carbon dots (C-dots) as building blocks to form C-dot assemblies. Compared to the individual C-dot, the self-assembled C-dots showed about 30 nm red-shift of absorption, resulting in the 5.1% increasing of photothermal conversion efficiency upon a 671 nm laser irradiation. More importantly, the C-dot assemblies enable them can be efficiently uptaken by cancer cells. Meanwhile, in vitro study demonstrated the C-dot assemblies can efficiently kill cancer cells than that of individual C-dot upon irradiation for 5 min at equivalent C-dot concentration. Our study may provide a new strategy for the efficient photothermal therapy of cancer based on C-dots.

Unravelling the Potential of Graphene Quantum Dots in Biomedicine and Neuroscience

“…Therefore, they can be exploited for multiple applications in the theranostic field, allowing imaging and phototherapy at the same time, making them more suitable with respect to other common organic dyes for bioimaging applications [103,104]. This technique is based on two features of materials that, when exposed to light at a specific wavelength (photosensitizers), generate cytotoxic reactive oxygen species (ROS, photodynamic therapy, PDT) [105] or heat (photothermal therapy, PTT) [106], capable of killing cells by photoablation. Since photosensitizers are generally harmless without light, tumor treatment can be specifically targeted by selective illumination, limiting damage to surrounding healthy tissues.…”

Recent advance of carbon dots in bio-related applications

“…The CuCDs nanosheets exhibited laser-triggered cytosolic delivery, lysosomal escape and nuclear-targeting nature. To enhance the cellular uptake or the EPR, Hou et al [183] conjugated the carboxylate CDs with PLGA-b-PEG-NH 2 through growth curves (n = 5) observed after different treatments (n = 5, P < 0.05 for each group); (g) the relative body weights of the nude mice increased continuously after different treatments; (h) representative photographs of the four groups after different treatments; (i) H&E stained images of tumors of the four groups after different treatments [150]. Reproduced from [11] with permission of The Royal Society of Chemistry.…”

Carbon dots for photothermal applications

“…Interestingly, Hou et al showed that PEG coating causes the red-shift of the fluorescence emission of CDs. These red emissive carbon dot assemblies demonstrated a higher PCE for in vitro eradication of cancer cells than their uncoated individual counterparts ( Hou et al, 2017 ). Additionally, specific chemical and physical modifications narrow the HOMO-LUMO band gap, redshifting the fluorescence emission peak and improving their photothermal performance ( Masha and Samuel Oluwafemi, 2022 ).…”