Red-emitting upconverting nanoparticles for photodynamic therapy in cancer cells under near-infrared excitation.

Upconverting nanoparticles (UCNPs) have attracted considerable attention as potential photosensitizer carriers for photodynamic therapy (PDT) in deep tissues. In this work, a new and efficient NIR photosensitizing nanoplatform for PDT based on red-emitting UCNPs is designed. The red emission band matches well with the efficient absorption bands of the widely used commercially available photosensitizers (Ps), benefiting the fluorescence resonance energy transfer (FRET) from UCNPs to the attached photosensitizers and thus efficiently activating them to generate cytotoxic singlet oxygen. Three commonly used photosensitizers, including chlorine e6 (Ce6), zinc phthalocyanine (ZnPc) and methylene blue (MB), are loaded onto the alpha-cyclodextrin-modified UCNPs to form Ps@UCNPs complexes that efficiently produce singlet oxygen to kill cancer cells under 980 nm near-infrared excitation. Moreover, two different kinds of drugs are co-loaded onto these nanoparticles: chemotherapy drug doxorubicin and PDT agent Ce6. The combinational therapy based on doxorubicin (DOX)-induced chemotherapy and Ce6-triggered PDT exhibits higher therapeutic efficacy relative to the individual means for cancer therapy in vitro.

Enhanced red emission from GdF3:Yb3+,Er3+ upconversion nanocrystals by Li+ doping and their application for bioimaging.

Under 980 nm near-infrared (NIR) excitation, upconversion luminescent (UCL) emission of GdF(3):Yb,Er upconversion nanoparticles (UCNPs) synthesized by a simple and green hydrothermal process can be tuned from yellow to red by varying the concentration of dopant Li(+) ions. A possible mechanism for enhanced red upconverted radiation is proposed. A layer of silica was coated onto the surface of GdF(3):Yb,Er,Li UCNPs to improve their biocompatibility. The silica-coated GdF(3):Yb,Er,Li UCNPs show great advantages in cell labeling and in vivo optical imaging. Moreover, GdF(3) UCNPs also exhibited a positive contrast effect in T(1)-weighted magnetic resonance imaging (MRI). These results suggest that the GdF(3) UCNPs could act as dual-modality biolabels for optical imaging and MRI.

Regulation effects of Co2+ on the construction of a Cu-Ni(OH)2@CoO nanoflower cluster heterojunction: a critical factor in obtaining a high-performance battery-type hybrid supercapacitor.

Electrode materials with a hierarchical nanostructure derived from transition metal-based compounds is an important branch of energy storage materials and have attracted widespread attention in recent years. Herein, a Cu-Ni(OH)2@CoO nanoflower cluster (Cu-Ni(OH)2@CoO NFCs) heterojunction was successfully constructed by a simple two-step hydrothermal method in the presence of Co2+. The optimized Cu-Ni(OH)2@CoO NFCs presented a high capacitive performance and outstanding cycle stability when used as a battery-type supercapacitive electrode material. In particular, an ultra-high areal specific capacitance of 5.8 F cm-2 (354.8 mA h g-1) at 1 mA cm-2 was obtained in 3 M KOH electrolyte. Even after 10 000 cycles, the capacitance still remained 98.4% of its initial value. All the experimental characterization results indicate that the excellent performance of the Cu-Ni(OH)2@CoO NFC self-supporting electrode can be attributed to the regulatory effect of Co2+ on the morphology and electronic structure, which is induced by the second hydrothermal process. More specifically, the transformations in the morphology and electronic structure will expose more active sites and accelerate charge transfer during the electrochemical reaction. Besides, the rapid oxidation reactions of multivalent transition metal ions and enhanced hydrophilicity promote the electrochemical reaction kinetics processes on the Cu-Ni(OH)2@CoO NFC electrode. This study provides a promising strategy for exploring low-cost and efficient electrode materials based on transition metal compounds for electrochemical energy storage.

Abnormal cGMP-dependent protein kinase I-mediated decidualization in preeclampsia.

Defective decidual function contributes to the pathogenesis of preeclampsia. However, the precise mechanism of defective decidua during preeclampsia has not been characterized. During decidualization, endometrial stromal cells undergo phenotypic changes that are consistent with mesenchymal-epithelial transition (MET). cGMP-dependent kinase protein I (PKGI)/VASP signaling is important in cell motility proliferation, differentiation and cell adhesion. To investigate this aim, we analyzed PKGI levels, phosphorylated VASP protein levels, and eNOS and sGC protein expression levels during pregnancy complicated by preeclampsia, which indicated that PKGI/VASP signaling function is decreased by the condition. Moreover, we evaluated the differential expression of genes that regulate MET in the decidua resulting from preeclampsia and healthy pregnancies. We discovered that vimentin mRNA levels are decreased in the decidua of preeclampsia, which indicates that excessive MET occurs in the decidua of preeclampsia pregnancies. A fundamental developmental MET program occurred in response to signaling pathways. These results suggest the important role of decreased PKGI/VASP signaling during excessive MET in the pathogenesis of preeclampsia.

An amorphous carbon nitride/NiO/CoN-based composite: a highly efficient nonprecious electrode for supercapacitors and the oxygen evolution reaction.

Due to their features of low cost, good corrosion resistance and environmental friendliness, transition metal oxides/nitrides are among the most promising materials for energy storage and conversion. Meanwhile, graphitic carbon nitride is a non-metallic polymer that has been widely used in the environmental and energy conversion fields due to its abundant precursor species and simple process of synthesis. In this study, an amorphous carbon nitride/NiO/CoN-based composite (Ni-Co-CN) is in situ fabricated via simple one-step pyrolysis; it displays high capacitive performance and efficient electrocatalytic capability for the oxygen evolution reaction (OER). Specifically, the optimized Ni-Co-CN electrode shows an ultra-high areal specific capacitance of 18.8 F cm-2 at 2 mA cm-2 in 3 M KOH electrolyte, and it retains 91.4% of its areal specific capacitance even after 10 000 cycles of CV scans. Upon being used as an electrocatalyst in the OER process, the overpotential of Ni-Co-CN can reach 195 mV versus a reference hydrogen electrode (RHE) at 10 mA cm-2, which is far lower than those of most reported Ni/Co-based catalysts. Additionally, the potential loss of Ni-Co-CN electrode is less than 1% after a long-term durability test over 60 h. The experimental results integrated with density functional theoretical calculations reveal that the excellent performance of the Ni-Co-CN self-supported electrode can be ascribed to the fast redox reduction of multi-valent transition metal ions, abundant surface defects and plentiful nano-scaled porous structures. This work provides a promising strategy for exploring methods to combine economic Ni/Co-based compounds with carbon-based materials to obtain low-cost yet efficient electrode materials for electrochemical energy storage and conversion.

Design of multifunctional alkali ion doped CaF2 upconversion nanoparticles for simultaneous bioimaging and therapy.

Herein, alkali ion doped CaF2 upconversion nanoparticles (UCNPs) were first reported as a multifunctional theranostic platform for dual-modal imaging and chemotherapy. Interestingly, we found that the alkali ions doping approach could efficiently enhance the upconversion luminescence (UCL) intensity, whereas slightly affect the phase and morphology of the resulting products. In order to further improve the UCL efficacy for bioimaging, a pristine CaF2 shell was grown on the CaF2:Yb, Er core surface to enhance the UCL intensity. After being transferred into hydrophilic UCNPs, these water-soluble UCNPs could be served as contrast agents for in vitro/in vivo UCL imaging and X-ray computed tomography (CT) imaging. Furthermore, the as-prepared UCNPs could also be employed as nano-carriers for drug delivery. Doxorubicin (DOX) can be easily loaded onto the UCNPs and the DOX-loaded UCNPs exhibit a good cell killing ability. Therefore, the multifunctional core-shell CaF2 UCNPs with UCL/CT imaging and drug carrier properties may find extensive applications in simultaneous imaging diagnosis and therapy.

A new near infrared photosensitizing nanoplatform containing blue-emitting up-conversion nanoparticles and hypocrellin A for photodynamic therapy of cancer cells.

The utilization of up-conversion nanoparticles (UCNPs) for photodynamic therapy (PDT) has gained significant interest due to their unique ability to convert near infrared light to UV/visible light. Previous work mainly focused on the fabrication of green and red emitting UCNPs to load photosensitizers (PSs) for PDT. In this work, we firstly developed a new multifunctional nanoplatform combining blue-emitting UCNPs with blue-light excited PS (hypocrellin A, HA) as a NIR photosensitizing nanoplatform for PDT of cancer cells. Tween 20 coated NaYbF4:Tm, Gd@NaGdF4 UCNPs (Tween 20-UCNPs) with strong blue up-conversion luminescence and good water dispersibility were prepared for use as PS carriers. The blue emission band matched well with the efficient absorption band of HA, thereby facilitating the resonance energy transfer from UCNPs to HA and then activating HA to produce singlet oxygen ((1)O2). The in vitro study showed that these Tween 20-UCNPs@HA complexes could efficiently produce (1)O2 to kill cancer cells under 980 nm NIR excitation. Moreover, these Gd(3+) and Yb(3+) containing nanoparticles also exhibited positive contrast effects in both T1 weighted magnetic resonance imaging (MRI) and computed tomography (CT) imaging, making them become a multifunctional platform for simultaneous PDT and bio-imaging.

Lanthanide ion-doped GdPO4 nanorods with dual-modal bio-optical and magnetic resonance imaging properties.

Here, dual-modal bioprobes for combined optical and magnetic resonance (MR) imaging are reported. Gadolinium orthophosphate (GdPO(4)) nanorods co-doped with light-emitting lanthanide ions have been successfully prepared through a hydrothermal method. An efficient downconversion luminescence from Ce/Tb or Eu doped GdPO(4) nanorods and upconversion luminescence from Yb/Er co-doped GdPO(4) nanorods are observed, respectively, which offers the optical modality for the nanoprobes. Notably, we first report the upconversion phenomenon based on the GdPO(4) matrix under 980 nm near infrared irradiation. The possibility of using these nanoprobes with downconversion and upconversion luminescent emissions for optical cell imaging is also demonstrated. Furthermore, these Gd(3+)-containing nanophosphors show good positive signal-enhancement ability when performed under a 4.7 T MR imaging scanner, indicating they have potential as T(1) MR imaging contrast agents. Thus, nanoprobes based on GdPO(4) nanophosphors are shown to provide the dual modality of optical and MR imaging.

Mn2+ dopant-controlled synthesis of NaYF4:Yb/Er upconversion nanoparticles for in vivo imaging and drug delivery.

Pure dark red emission (650-670 nm) of NaYF(4):Yb/Er upconversion nanoparticles (UCNPs) is achieved by manganese ions (Mn(2+)) doping. In addition, the Mn(2+)-doping can also control the crystalline phase and size of the resulting UCNPs simultaneously. Drug delivery studies suggest the promise of these UCNPs as drug carriers for intracellular drug delivery and eventually as a multifunctional nanoplatform for simultaneous diagnosis and therapy.