Biomedical applications of multifunctional plasmonic nanoparticles

Localized surface plasmon resonance biosensors: the basic principle of biomolecule detection. First, the plasmonic nanoparticle deposition occurs on a glass slide, whose optical properties can be monitored in situ (step 1, gray line). Then, the plasmonic surface is biofunctionalized with the ligand biomolecule ( , step 2, red line). The addition of the corresponding biomarker analyte ( ) follows (step 3, green line) that selectively attaches on the ligand biomolecule ( ). The sensor response corresponds to the Δλ plasmon peak shift, which depends on the analyte concentration.

Localized surface plasmon resonance biosensors: the basic principle of biomolecule detection. First, the plasmonic nanoparticle deposition occurs on a glass slide, whose optical properties can be monitored in situ (step 1, gray line). Then, the plasmonic surface is biofunctionalized with the ligand biomolecule ( , step 2, red line). The addition of the corresponding biomarker analyte ( ) follows (step 3, green line) that selectively attaches on the ligand biomolecule ( ). The sensor response corresponds to the Δλ plasmon peak shift, which depends on the analyte concentration.

Different morphologies of multifunctional plasmonic nanoparticles that include magnetism, photoluminescence, dipsersibility in aqueous solutions, and enhanced stability against degradation by alloying.

Bioluminescent imaging of tumors in mice following laser irradiation over time and gold nanoshell treatment. The gold‐nanoshell‐treated mice displayed complete or partial tumor loss, while the tumor volume in the mouse of the control group only increased. The survival of the treated mice is significantly longer than the control group mice, as more than 50% of the treated mice remained tumor‐free for more than 90 days. (Reprinted with permission from Ref 38. Copyright 2011 Springer)

Localized surface plasmon resonance biosensors: the basic principle of biomolecule detection. First, the plasmonic nanoparticle deposition occurs on a glass slide, whose optical properties can be monitored in situ (step 1, gray line). Then, the plasmonic surface is biofunctionalized with the ligand biomolecule ( , step 2, red line). The addition of the corresponding biomarker analyte ( ) follows (step 3, green line) that selectively attaches on the ligand biomolecule ( ). The sensor response corresponds to the Δλ plasmon peak shift, which depends on the analyte concentration.

Localized surface plasmon resonance biosensors: the basic principle of biomolecule detection. First, the plasmonic nanoparticle deposition occurs on a glass slide, whose optical properties can be monitored in situ (step 1, gray line). Then, the plasmonic surface is biofunctionalized with the ligand biomolecule ( , step 2, red line). The addition of the corresponding biomarker analyte ( ) follows (step 3, green line) that selectively attaches on the ligand biomolecule ( ). The sensor response corresponds to the Δλ plasmon peak shift, which depends on the analyte concentration.

(a) A hybrid nanoparticle consisting of ZnO quantum dots, plasmonic gold nanoparticles, and anticancer drug in a thermally responsive hydrogel. (b) The ZnO quantum dots enable the nanoparticle detection under a fluorescent microscope (yellow signal), while when these nanoparticles are irradiated by a near‐IR laser, the hydrogel shrinks, releasing, therefore, the anticancer drug (c). (Reprinted with permission from Ref 83. Copyright 2011 Wiley‐VCH)

Hybrid magnetic–plasmonic core‐shell nanoparticles. Dark‐field images of unlabeled breast cancer cells (a) and of nanoparticle‐labeled cells (b). The hybrid nanoparticles have been selectively attached on the cells and can be clearly detected (scale bar is 30 µm). When these cells are irradiated by a near‐IR laser beam, only the labeled cells are destroyed (c, green marks the living cells), while the cells incubated with PEGylated nanoparticles do not show any effect (d). Scale bar is 100 µm. (Reprinted with permission from Ref 66. Copyright 2007 IOP Publishing)