Nanocomposites Containing Silica-Coated Gold–Silver Nanocages and Yb–2,4-Dimethoxyhematoporphyrin: Multifunctional Capability of IR-Luminescence Detection, Photosensitization, and Photothermolysis

Abstract

We describe novel composite nanoparticles consisting of a gold-silver nanocage core and a mesoporous silica shell functionalized with the photodynamic sensitizer Yb-2,4-dimethoxyhematoporphyrin (Yb-HP). In addition to the long-wavelength plasmon resonance near 750-800 nm, the composite particles exhibited a 400-nm absorbance peak and two fluorescence peaks, near 580 and 630 nm, corresponding to bound Yb-HP. The fabricated nanocomposites generated singlet oxygen under 630-nm excitation and produced heat under laser irradiation at the plasmon resonance wavelength (750-800 nm). In particular, we observed enhanced killing of HeLa cells incubated with nanocomposites and irradiated by 630-nm light. Furthermore, an additional advantage of fabricated conjugates was an IR-luminescence band (900-1060 nm), originating from Yb(3+) ions of bound Yb-HP and located in the long-wavelength part of the tissue transparency window. This modality was used to control the accumulation and biodistribution of composite particles in mice bearing Ehrlich carcinoma tumors in a comparative study with intravenously injected free Yb-HP molecules. Thus, these multifunctional nanocomposites seem an attractive theranostic platform for simultaneous IR-luminescence diagnostic and photodynamic therapy owing to Yb-HP and for plasmonic photothermal therapy owing to Au-Ag nanocages.

Synthesis and applications of multifunctional composite nanomaterials

“…crucial for optimal light absorption and charge separation), improved mechanical stability, as well as specific magnetic properties essential for catalysis. Khlebtsov et al (2011) fabricated composite nanoparticles (Figure 4) consisting of a gold-silver nanocage core and a mesoporous silica shell functionalized with the photodynamic sensitizer Yb-2,4-dimethoxyhematoporphyrin (Yb-HP). In addition to the long-wavelength plasmon resonance near 750-800 nm, the composite particles exhibited a 400-nm absorbance peak and two fluorescence peaks, near 580 and 630 nm, corresponding to the bond Yb-HP.…”

“…This modality was used to control the accumulation and biodistribution of composite particles in mice bearing Ehrlich carcinoma tumors in a comparative study with intravenously injected free Yb-HP molecules. The multifunctional nanocomposite seems to be an attractive theranostic platform for simultaneous IR-luminescence diagnostic and photodynamic therapy owing to Yb-HP and for plasmonic photothermal therapy owing to Au-Ag nanocages (Khlebtsov et al 2011). Chen et al (2011) synthesized multifunctional nanoparticles composed of Fe 3 O 4 -Au nanocomposite core and a porous silica shell (pSiO 2 ), aimed at achieving magnetic and optical properties of magnetic-gold nanocomposite, shown in Figure 5.…”

Functional Inorganic Nanohybrids for Biomedical Diagnosis

“…These hybrid structures were used to perform the accurate quantitative analysis of the effect of the metal on quantum dot photoluminescence intensity. Khlebtsov et al [60] preformed the silica coating on Au-Ag nanocages through adding water-ammonia solution and TEOS to the reaction solution containing Au-Ag particles. Silica-coated Au-Ag nanocages were then functionalized with photodynamic sensitizer Yb-2,4-dimethoxyhematoporphyrin to form the nanocomposites potential in multifunctional capability of IR-luminescence detection, photosensitization, and photothermolysis.…”

Progress of nanotechnology for phototherapy: Fundamentals and applications

“…NPs for dual-modality of fluorescence and magnetic resonance imaging-guided, and dual-therapy using photothermal therapy (PTT) and photodynamic therapy (PDT) have been developed recently [11][12][13][14][15][16][17][18][19][20][21][22], where synergic treatment modalities combining PDT with PTT could overcome current limitations of PDT, thus achieving enhanced anticancer efficacy.…”