Novel Mn3[Co(CN)6]2@SiO2@Ag Core-Shell Nanocube: Enhanced Two-Photon Fluorescence and Magnetic Resonance Dual-Modal Imaging-Guided Photothermal and Chemo-therapy

The versatile Mn-3[Co(CN)(6)](2)@SiO2@Ag core-shell NCs are prepared by a simple coprecipitation method. Ag nanoparticles with an average diameter of 12 nm deposited on the surface of Mn-3[Co(CN)(6)](2)@SiO2 through S-Ag bonding are fabricated in ethanol solution by reducing silver nitrate (AgNO3) with NaBH4. The NCs possess T-1-T-2 dual-modal magnetic resonance imaging ability. The inner Prussian blue analogs (PBAs) Mn-3[Co(CN)(6)](2) exhibit bright two-photon fluorescence (TPF) imaging when excited at 730 nm. Moreover, the TPF imaging intensity displays 1.85-fold enhancement after loading of Ag nanoparticles. Besides, the sample also has multicolor fluorescence imaging ability under 403, 488, and 543 nm single photon excitation. The as-synthesized Mn-3[Co(CN)(6)](2)@SiO2@Ag NCs show a DOX loading capacity of 600 mg g(-1) and exhibit an excellent ability of near-infrared (NIR)-responsive drug release and photothermal therapy (PTT) which is induced from the relative high absorbance in NIR region. The combined chemotherapy and PTT against cancer cells in vitro test shows high therapeutic efficiency. The multimodal treatment and imaging could lead to this material a potential multifunctional system for biomedical diagnosis and therapy.