PEGylated Micelle Nanoparticles Encapsulating a Non‐Fluorescent Near‐Infrared Organic Dye as a Safe and Highly‐Effective Photothermal Agent for In Vivo Cancer Therapy

Abstract

Photothermal therapy (PTT), as a minimally invasive and highly effective cancer treatment approach, has received widespread attention in recent years. Tremendous effort has been devoted to explore various types of photothermal agents with high near-infrared (NIR) absorbance for PTT cancer treatment. Despite many exciting progresses in the area, effective yet safe photothermal agents with good biocompatibility and biodegradability are still highly desired. In this work, a new organic PTT agent based on polyethylene glycol (PEG) coated micelle nanoparticles encapsulating a heptamethine indocyanine dye IR825 is developed, showing a strong NIR absorption band and a rather low quantum yield, for in vivo photothermal treatment of cancer. It is found that the IR825-PEG nanoparticles show ultra-high in vivo tumor uptake after intravenous injection, and appear to be an excellent PTT agent for tumor ablation under a low-power laser irradiation, without rendering any appreciable toxicity to the treated animals. Compared with inorganic nanomaterials and conjugated polymers being explored in PTT, the NIR-absorbing micelle nanoparticles presented here may have the least safety concern while showing excellent treatment effi cacy, and thus may be a new photothermal agent potentially useful in clinical applications.

A 3D-printed scaffold with MoS2 nanosheets for tumor therapy and tissue regeneration

“…5,6 In recent years, photothermal therapy (PTT), a minimally invasive and highly efficient antitumor approach, has been demonstrated to enhance tumor therapeutic efficacy and reduce side effects in numerous pre-clinical animal studies. 2,[7][8][9][10] PTT functions with the assistance of certain photothermal agents, which can convert near-infrared (NIR) laser light into heat and ablate tumor tissue by inducing hyperthermia. 2,11 Therefore, it is essential to fabricate a novel bifunctional biomaterial with photothermal therapeutic capacity for treating tumor cells and bone regeneration capacity for repairing bone defects derived from surgical resection.…”

Conductive polymer-based nanoparticles for laser-mediated photothermal ablation of cancer: synthesis, characterization, and in vitro evaluation

“…demonstrating the potential of CPNPs as PTT agents have been carried out by Liu et al 12,13,33 Their group demonstrated that polypyrrole and PEDOT:PSS NPs can both act as effective PTT agents. 12,13 Separately, NPs composed of 2-ethylhexyl cyclopentadithiophene copolymerized with 2,1,3-benzothiadiazole or 2,1,3-benzoselenadiazole synthesized by MacNeill et al also proved to be effective PTT agents.…”

Recent advances in the development of organic photothermal nano-agents

“…agents based on PEGylated micelles encapsulating a heptamethine indocyanine dye, IR825 [40]. The IR825-PEG nanoparticles showed much better photothermal stability compared to ICG, efficient tumor passive homing as a result of the enhanced permeability and retention (EPR) effect of cancerous tumors, and were able to induce effective photothermal tumor ablation under NIR laser irradiation.…”

“…Several commonly used NIR dyes in PTT are listed in Fig. 1 [24,31,[38][39][40][41]. Generally speaking, many NIR dyes can simultaneously serve as a fluorescent imaging probe as well as a photothermal agent [24,34,36].…”