Plasmonic Copper Sulfide Nanocrystals Exhibiting Near-Infrared Photothermal and Photodynamic Therapeutic Effects

Abstract

Recently, plasmonic copper sulfide (Cu2-xS) nanocrystals (NCs) have attracted much attention as materials for photothermal therapy (PTT). Previous reports have correlated photoinduced cell death to the photothermal heat mechanism of these NCs, and no evidence of their photodynamic properties has been reported yet. Herein we have prepared physiologically stable near-infrared (NIR) plasmonic copper sulfide NCs and analyzed their photothermal and photodynamic properties, including therapeutic potential in cultured melanoma cells and a murine melanoma model. Interestingly, we observe that, besides a high PTT efficacy, these copper sulfide NCs additionally possess intrinsic NIR induced photodynamic activity, whereupon they generate high levels of reactive oxygen species. Furthermore, in vitro and in vivo acute toxic responses of copper sulfide NCs were also elicited. This study highlights a mechanism of NIR light induced cancer therapy, which could pave the way toward more effective nanotherapeutics.

Metal–Organic‐Framework‐Derived Mesoporous Carbon Nanospheres Containing Porphyrin‐Like Metal Centers for Conformal Phototherapy

“…No noticeable particle aggregation or change of morphology was observed after irradiation for 10 min ( Figure S10, Supporting Information), suggesting the dispersions have good stability. Additionally, the photothermal conversion effi ciency ( η ) was calculated as ≈33.0%, much higher than most other photothermal agents such as Au nanorods (21.0%), [ 17 ] Au shells (13.0%), [ 17 ] Bi 2 S 3 nanorods (28.1%), [ 27 ] and Cu 2− x S nanoparticles (16.3%) [ 18 ] ( Figure S11, Supporting Information). The strong photothermal conversion capacity and excellent photo stability of PMCS suggest that they have great potential as photo thermal agents.…”

“…To establish the intrinsic photodynamic properties of PMCS, we measured the production of ROS using the dye dichlorofl uorescein diacetate (DCFH-DA), which is oxidized to 2,7-dichlorofl uorescein (DCF) (excitation/emission wavelength: 495 nm/529 nm) by ROS. [ 18 ] A PMCS-phosphate-buffered saline (PBS) solution and pure PBS were irradiated under an NIR laser (808 nm, 1 W cm −2 ) for 10 min. Subsequently, DCFH-DA dye was added and the solution was left for 2.…”

Near-infrared radiation absorption properties of covellite (CuS) using first-principles calculations

“…6 Recently, CuS has attracted attention due to its localized surface plasmonic absorption in the near-infrared (NIR) region, making it a potential candidate for other applications including photothermal cancer therapy, [7][8][9][10] biomedical imaging 10,11 and solar radiation absorption. 12 Although several theoretical 13,14 and experimental 15,16 studies have been carried out in an attempt to understand the electronic structure, chemical bonding and NIR absorption of CuS, 16 the explanation behind its NIR absorption remains unclear.…”

pH-Sensitive self-assembling nanoparticles for tumor near-infrared fluorescence imaging and chemo–photodynamic combination therapy

“…15 In addition, because these photosensitizers also emit fluorescence signals under light excitation, they can serve as a contrast agent for tumor fluorescence imaging. 16 Although PDT has been used to treat some tumors, the potential of photosensitizers to be widely applied to cancer therapy is still hampered by many limitations such as their water-insolubility and low tumor targeted accumulation.…”