Coordination polymer hybridized Au nanocages (AuNC@CPs) were prepared via a dialysis process by combining Au nanocages with a coordination polymer, which was derived from (pq)2Ir(Hdcbpy) and Dy(OOCCH3)3. After hybridization, the localized surface plasmon resonance (LSPR) peak of the AuNC@CPs exhibited an evident red shift in comparison with that of the Au nanocages, which was due to a variation in the dielectric constant caused by the coordination polymer. Notably, inspired by their excellent photothermal, photoacoustic, and magnetic properties in solution, AuNC@CPs were used for near-infrared (NIR)-driven photothermal therapy (PTT) guided by photoacoustic (PA) and magnetic resonance (MR) imaging in vivo. Owing to their remarkable performance, the AuNC@CPs would represent promising nanoprobes for theranostics.

With the development of personalized medicine, the research of theranostic agents with good biocompatibility, stability, and targeting properties remains meaningful. Herein, we report a two-step process to construct heteropoly blue (HPB) doped polymer nanoparticles (HPB/P4VP-b-PEO NPs) with efficient near-infrared (NIR) light absorption and photothermal conversion efficiency of ∼23% to simultaneously perform photoacoustic imaging and photothermal therapy in vivo. After intravenous injection into the 4T1 xenograft model, in vivo photoacoustic imaging confirmed the targeted property of HPB/P4VP-b-PEO NPs due to the enhanced EPR effect. The photoacoustic signal in the tumor at 24 h p.i. was more than ∼10 times that of the pre-injection group. By virtue of their EPR effect, HPB/P4VP-b-PEO NPs achieved a good photothermal therapeutic efficacy in vivo.

Magnetic core–shell ferrite nanocubes (MNCs) were prepared by a two-step pyrolysis. The MNCs not only exhibit an excellent magnetothermal effect, but also can be used as T2 magnetic resonance (MR) imaging agents. To obtain their good biocompatibility and targeting ability, MNCs were modified with poly(ethylene glycol) (PEG) and hyaluronic acid (HA). To further construct an integrated nanoplatform for theranostics, doxorubicin (DOX) was loaded onto the surface of MNCs by pH and heat sensitive chemical bonding. Notably, the MNCs showed a great stability and magnetothermal effect. Moreover, they showed negligible toxicity and synergistic therapy in vitro. Meanwhile, their MR imaging in vivo was further verified. A novel integrated nanoplatform facilitates excellent targeted MR imaging guided synergism of magnetothermal and chemotherapy. The multifunctional nanocubes will be capable of playing a vital role in future cancer therapy.

Iridium complex loaded polypyrrole nanoparticles (Ir-PPy NPs) have been prepared through the polymerization of pyrrole by Fe3+ in the presence of polyvinyl alcohol (PVA) and iridium complex. The Ir-PPy NPs exhibited a photothermal effect and the generation of singlet oxygen. In the Ir-PPy NPs, PPy could convert light energy to heat with a photothermal conversion efficiency of ∼35.5% when irradiated by a 730 nm continuous wave (CW) laser, and the iridium complex could generate singlet oxygen when irradiated by a 730 nm CW laser, as confirmed by monitoring the consumption of DPBF at 410 nm.

A magnetic sensor for detection of Pb2+ has been developed based on Fe/Fe3O4 nanoparticles modified by 3-(3,4-dihydroxyphenyl)propionic acid (DHCA). The carboxyl groups of DHCA have a strong affinity to coordination behavior of Pb2+ thus inducing the transformation of Fe/Fe3O4 nanoparticles from a dispersed to an aggregated state with a corresponding decrease, then increase in transverse relaxation time (T2) of the surrounding water protons. Upon addition of the different concentrations of Pb2+ to an aq. solution of DHCA functionalized Fe/Fe3O4 nanoparticles (DHCA-Fe/Fe3O4 NPs) ([Fe] = 90 μmol/L), the change of T2 values display a good linear relationship with the concentration of Pb2+ from 40 μmol/L to 100 μmol/L and from 130 μmol/L to 200 μmol/L, respectively. Owing to the especially strong interaction between DHCA and Pb2+, DHCA-Fe/Fe3O4 NPs exhibited a high selectivity over other metal ions.Functionalized Fe/Fe3O4 nanoparticles was developed to detect Pb2+.

Au-Fe3O4 nanocomposites were synthesized and modified with l-(2-mercaptoethyl)-1,2,3,4,5,6-hexanhydro-s-triazine-2,4,6-trione (MTT) for the bimodal detection of melamine. The bimodal detection is based on the aggregation of Au-Fe3O4@MTT nanoparticles (NPs) from the dispersed state upon the formation of special triple hydrogen bonds between melamine and MTT. This phenomenon causes the red shift of the absorption peak and the increase of the spin–spin relaxation time (T2) of the water protons upon addition of melamine at different concentrations to an aqueous solution of Au-Fe3O4@MTT NPs. Furthermore, the dual-modal method exhibits a clear selectivity toward melamine.

The mitochondrion is a promising target for diagnosis and therapy. Mitochondrial-targeting silica-coated manganese oxide nanoparticles (MnO@SiO2-PPh3+ NPs) were successfully synthesized to explore the mitochondrial cytotoxicity of nanoparticles. The mitochondrial targeting property was confirmed by a laser scanning confocal microscopy experiment. Even after incubation for only 4 h, the cytotoxicity of MnO@SiO2-PPh3+ NPs against cancer cells was obvious; the ATP content was significantly decreased to 40%; and the mitochondrial membrane potential was depleted. All of these results indicated the collapse of mitochondrial function and the start of a cell apoptosis pathway. Our findings suggest that mitochondrial-mediated

Water-soluble coordination polymer nanoparticles (Ir–Gd CPPs) were conveniently synthesized in high yields in the presence of polyvinylpyrrolidone (PVP), adopting magnetic Gd(III) ions, and phosphorescent iridium complexes with carboxyl groups as building blocks. The Ir–Gd CPPs showed good stability in simulated biological media and low cytotoxicity toward a model line of HeLa cancer cells. The Ir–Gd CPPs exhibited absorption in the visible region, red phosphorescence centered at 560 nm, and higher longitudinal relaxivity (r1) of ∼29.5 mM–1 s–1 in a 3 T MRI system. Furthermore, the effective uptake of Ir–Gd CPPs by HeLa cells was confirmed by confocal laser scanning microscopy and flow cytometry, suggesting they may be useful as an optical probe for living cells. The generation of 1O2 upon irradiation with a visible light prompted an investigation into the possibility of using Ir–Gd CPPs in photodynamic therapy. After incubation with 200 μg mL–1 of Ir–Gd CPPs for 6 h, the viability of HeLa cells was only ∼16.6% after irradiation with a visible light (λ > 400 nm, 300 mW cm–2).

Phosphorescent nanospheres of a carboxyl-functionalized iridium complex ([Ir(ppy)2(Hdcbpy)], ppy: 2-phenylpyridine; Hdcbpy: 4-carboxy-2,2′-bipyridyl-4′-carboxylate) were prepared by a conventional precipitation method. Driven by hydrogen bond interaction between carboxylic groups of the complex and the guest molecule tris(imidazoline), these nanospheres can be transformed into 1-dimensional nanowires in the presence of tris(imidazoline) at the concentration of the iridium complex higher than 4.8 mM, while nanowires change back to nanospheres with the diameter obviously smaller than that of the sole complex of [Ir(ppy)2(Hdcbpy)]. The interaction between carboxylic groups and tris(imidazoline) molecules was confirmed by FT-IR spectra. The structures of the nanowires and nanospheres were further studied by XRD diffraction analysis. With the morphological transformation from nanospheres to nanowires, the phosphorescence of nanostructures was blue shifted from 590 to 564 nm.

Phosphorescent nanoscale coordination polymer nanoparticles (NCPs) were conveniently synthesized by phosphorescent carboxyl-functionalized iridium complexes as a building block and rare earth Y(III) ions as metallic nodes. They reveal to be uniform nanospheres with average diameter around 200 nm. Multi-color emission from blue to orange was obtained by tuning the ratios of two iridium complexes with energy transfer between them. Furthermore, the white-light emission with CIE coordinates of (0.319, 0.388) was performed.Highlights► Phosphorescent nanoscale coordination polymer nanoparticles (NCPs) were conveniently synthesized. ► The phosphorescent carboxyl-functionalized iridium complex was a building block with rare earth Y(III) ions as metallic nodes. ► Multi-color emission from blue to orange was obtained.

A o-hydroxybenzoyl-(N-butyl-4,6-naphthamimide) hydrazone (1) has been synthesized. Compound 1 displayed high selectivity for F− and Cu2+ with UV/vis absorption and fluorescence spectra, respectively. In the presence of F−, while the absorption peak of 1 showed the red shift, its fluorescent intensity decreased due to deprotonation interaction. In the presence of Cu2+, both the absorption and fluorescence peaks decreased because of the coordination interaction.

A MRI nanosensor for Hg (II) was developed based on superparamagnetic iron oxide nanoparticles (SPIO NPs). The detection mechanism is attributed to Hg (II)-induced nanoassembly of thymidine-functionalized SPIO NPs from a dispersed to an aggregated state with a corresponding decrease in the transverse relaxation time (T2) of adjacent water protons. Furthermore, an enhancement of transverse relaxation rates (1/T2) showed the high selectivity for Hg (II) compared with other transition and main group metal ions.

Magneto-phosphorescent d–f coordination polymer nanoparticles (f-CPPs) were conveniently synthesized by phosphorescent carboxyl-functionalized iridium complexes as building blocks and magnetic Gd(III) ions as metallic nodes. They reveal uniform hollow spheres with an average diameter of around 60 nm and wall thickness of about 10 nm. Water soluble f-CPPs were obtained by polyvinylpyrolidone modification (denoted as f-CPPs@PVP), which had an intense red phosphorescence, moderate longitudinal relaxivity (r1) and low cytotoxicity. Furthermore, inductively coupled plasma atomic emission spectroscopy (ICP-AES) and confocal laser scanning microscopy (CLSM) confirmed f-CPPs@PVP could be taken up by living cells effectively. Therefore, they should be a novel nano-bioprobe for the multimodal imaging of cancer cells.

Magnetic core–shell ferrite nanocubes (MNCs) were prepared by a two-step pyrolysis. The MNCs not only exhibit an excellent magnetothermal effect, but also can be used as T2 magnetic resonance (MR) imaging agents. To obtain their good biocompatibility and targeting ability, MNCs were modified with poly(ethylene glycol) (PEG) and hyaluronic acid (HA). To further construct an integrated nanoplatform for theranostics, doxorubicin (DOX) was loaded onto the surface of MNCs by pH and heat sensitive chemical bonding. Notably, the MNCs showed a great stability and magnetothermal effect. Moreover, they showed negligible toxicity and synergistic therapy in vitro. Meanwhile, their MR imaging in vivo was further verified. A novel integrated nanoplatform facilitates excellent targeted MR imaging guided synergism of magnetothermal and chemotherapy. The multifunctional nanocubes will be capable of playing a vital role in future cancer therapy.

Magneto-phosphorescent d–f coordination polymer nanoparticles (f-CPPs) were conveniently synthesized by phosphorescent carboxyl-functionalized iridium complexes as building blocks and magnetic Gd(III) ions as metallic nodes. They reveal uniform hollow spheres with an average diameter of around 60 nm and wall thickness of about 10 nm. Water soluble f-CPPs were obtained by polyvinylpyrolidone modification (denoted as f-CPPs@PVP), which had an intense red phosphorescence, moderate longitudinal relaxivity (r1) and low cytotoxicity. Furthermore, inductively coupled plasma atomic emission spectroscopy (ICP-AES) and confocal laser scanning microscopy (CLSM) confirmed f-CPPs@PVP could be taken up by living cells effectively. Therefore, they should be a novel nano-bioprobe for the multimodal imaging of cancer cells.

PEGylated nanosized graphene oxides (NGO–PEG) and related derivatives have attracted extensive attention owing to their unique properties, which confer significant theranostic benefits for cancer treatment. The size of NGO–PEG varies largely, from tens of nanometers to micrometers, and the optimal size range with the most efficient tumor retention in vivo remains to be determined. For this purpose, we designed different sizes of NGO–PEG, specifically, ultra-small NGO–PEG (usNGO–PEG, sub-50 nm) and NGO–PEG (over 50 nm) and compared their biological behaviors in vitro and in vivo. Both NGO–PEGs exhibited nearly identical physicochemical properties and low cytotoxicity. Following Cy5.5 tagging, confocal microscopy fluorescence imaging revealed faster and higher dynamic cellular uptake of usNGO–PEG than NGO–PEG. Longitudinal, non-invasive visualization of the NGO–PEGs using single proton emission computed tomography (SPECT) imaging with 125I-radiolabeling revealed that tumor retention of usNGO–PEG was significantly higher and longer compared to that of NGO–PEG, whereas the blood circulation and biodistribution of both NGO–PEGs were similar in major organs. In conclusion, Sub-50 nm was further confirmed to be the favorable size for efficient tumor accumulation of PEGylated GO via the enhanced permeability and retention (EPR) effect. We propose that the sub-50 nm NGO–PEG designed in this study may be effectively utilized to develop novel PEGylated GO-based nanoplatforms for multifunctional cancer nanotheranostics.

With the development of personalized medicine, the research of theranostic agents with good biocompatibility, stability, and targeting properties remains meaningful. Herein, we report a two-step process to construct heteropoly blue (HPB) doped polymer nanoparticles (HPB/P4VP-b-PEO NPs) with efficient near-infrared (NIR) light absorption and photothermal conversion efficiency of ∼23% to simultaneously perform photoacoustic imaging and photothermal therapy in vivo. After intravenous injection into the 4T1 xenograft model, in vivo photoacoustic imaging confirmed the targeted property of HPB/P4VP-b-PEO NPs due to the enhanced EPR effect. The photoacoustic signal in the tumor at 24 h p.i. was more than ∼10 times that of the pre-injection group. By virtue of their EPR effect, HPB/P4VP-b-PEO NPs achieved a good photothermal therapeutic efficacy in vivo.

Phosphorescent nanospheres of a carboxyl-functionalized iridium complex ([Ir(ppy)2(Hdcbpy)], ppy: 2-phenylpyridine; Hdcbpy: 4-carboxy-2,2′-bipyridyl-4′-carboxylate) were prepared by a conventional precipitation method. Driven by hydrogen bond interaction between carboxylic groups of the complex and the guest molecule tris(imidazoline), these nanospheres can be transformed into 1-dimensional nanowires in the presence of tris(imidazoline) at the concentration of the iridium complex higher than 4.8 mM, while nanowires change back to nanospheres with the diameter obviously smaller than that of the sole complex of [Ir(ppy)2(Hdcbpy)]. The interaction between carboxylic groups and tris(imidazoline) molecules was confirmed by FT-IR spectra. The structures of the nanowires and nanospheres were further studied by XRD diffraction analysis. With the morphological transformation from nanospheres to nanowires, the phosphorescence of nanostructures was blue shifted from 590 to 564 nm.