Rapid, microwave-assisted synthesis of Gd2O3 and Eu:Gd2O3 nanocrystals: characterization, magnetic, optical and biological studies

Synthesis and Characterisation of Nanocrystalline CoxFe1-xGDC Powders as a Functional Anode Material for the Solid Oxide Fuel Cell

The necessity for high operational temperatures presents a considerable obstacle to the commercial viability of solid oxide fuel cells (SOFCs). The introduction of active co-dopant ions to polycrystalline solid structures can directly impact the physiochemical and electrical properties of the resulting composites including crystallite size, lattice parameters, ionic and electronic conductivity, sinterability, and mechanical strength. This study proposes cobalt-iron-substituted gadolinium-doped ceria (CoxFe1-xGDC) as an innovative, nickel-free anode composite for developing ceramic fuel cells. A new co-precipitation technique using ammonium tartrate as the precipitant in a multi-cationic solution with Co2+, Gd3+, Fe3+, and Ce3+ ions was utilized. The physicochemical and morphological characteristics of the synthesized samples were systematically analysed using a comprehensive set of techniques, including DSC/TGA for a thermal analysis, XRD for a crystallographic analysis, SEM/EDX for a morphological and elemental analysis, FT-IR for a chemical bonding analysis, and Raman spectroscopy for a vibrational analysis. The morphological analysis, SEM, showed the formation of nanoparticles (≤15 nm), which corresponded well with the crystal size determined by the XRD analysis, which was within the range of ≤10 nm. The fabrication of single SOFC bilayers occurred within an electrolyte-supported structure, with the use of the GDC as the electrolyte layer and the CoO-Fe2O3/GDC composite as the anode. SEM imaging and the EIS analysis were utilized to examine the fabricated symmetrical cells.

Pentacenequinone-Modulated 2D GdSn-PQ Nanosheets as a Fluorescent Probe for the Detection of Enrofloxacin in Biological and Environmental Samples

The fate and effects of fluoroquinolone antibacterial (FQ) on the environment are important since there appears to be a surge in FQ resistance like enrofloxacin (ENR) in both environmental and clinical organisms. Numerous reports indicate that the sensing capabilities of these antibiotics need to be improved. Here, we have investigated the interaction of ENR with our synthesized pentacenequinone-modulated gadolinium-tin (GdSn-PQ) nanosheets and the formation of intermolecular interactions that caused the occurrence of aggregation-induced emission enhancement. The concept for designing hybrid metallic nanosheets comes from the unique features inherited from the parent organic precursor. Due to the distinct interaction between ENR and GdSn-PQ, the interstate conversion (ISC) between GdSn-PQ and ENR induces a significant wavelength shift in photoluminescence (PL), improving reliability, selectivity, and visibility compared to quenching- or AIEE-based methods without peak shifts, allowing for highly sensitive and visually detectable analyses. The fluorescence signal of GdSn-PQ exhibited a linear relationship (R2 = 0.9911), with the added ENR concentrations ranging from 5 to 90 nM, with a detection limit of 0.10 nM. We have demonstrated its potential and wide use in the detection of ENR in biological samples (human urine and blood serum) and environmental samples (tap water and seawater) with a recovery rate of 98- 108%. The current approach has demonstrated that the 2D GdSn-PQ nanosheet is a novel and powerful platform for future biological and environmental studies.

Potential-Resolved Ratiometric Aptasensor for Sensitive Acetamiprid Analysis Based on Coreactant-free Electrochemiluminescence Luminophores of Gd-MOF and "Light Switch" Molecule of [Ru(bpy)2dppz]2

For conventional potential-resolved ratiometric electrochemiluminescence (ECL) systems, the introduction of multiplex coreactants is imperative. However, the undesirable interactions between different coreactants inevitably affect analytical accuracy and sensitivity. Herein, through the coordination of aggregation-induced emission ligands with gadolinium cations, the self-luminescent metal-organic framework (Gd-MOF) is prepared and serves as a novel coreactant-free anodic ECL emitter. By the intercalation of [Ru(bpy)2dppz]2+ with light switch effect into DNA duplex, one high-efficiency cathodic ECL probe is obtained using K2S2O8 as a coreactant. In the presence of acetamiprid, the strong affinity between the target and its aptamer induces the release of [Ru(bpy)2dppz]2+, resulting in a decreasing cathode signal and an increasing anode signal owing to the ECL resonance energy transfer from Gd-MOF to [Ru(bpy)2dppz]2+. In this way, an efficient dual-signal ECL aptasensor is constructed for the ratiometric analysis of acetamiprid, exhibiting a remarkably low detection limit of 0.033 pM. Strikingly, by using only one exogenous coreactant, the cross interference from multiple coreactants can be eliminated, thus improving the detection accuracy. The developed high-performance ECL sensing platform is successfully applied to monitor the residual level of acetamiprid in real samples, demonstrating its potential application in the field of food security.

Anomalous thermal activation of green upconversion luminescence in Yb/Er/ZnGdO self-assembled microflowers for high-sensitivity temperature detection

Non-contact optical temperature detection has shown a great promise in biological systems and microfluidics because of its outstanding spatial resolution, superior accuracy, and non-invasive nature. However, the thermal quenching of photoluminescence significantly hinders the practical applications of optical temperature probes. Herein, we report thermally enhanced green upconversion luminescence in Yb/Er/ZnGdO microflowers by a defect-assisted thermal distribution mechanism. A 1.6-fold enhancement in green emission was demonstrated as the temperature increased from 298 K to 558 K. Experimental results and dynamic analysis demonstrated that this behavior of thermally activating green upconversion luminescence originates from the emission loss compensation, which is attributed to thermally-induced energy transfer from defect levels to the green emitting level. In addition, the Yb/Er/ZnGdO microflowers can act as self-referenced radiometric optical thermometers. The ultrahigh absolute sensitivity of 1.61% K-1 and an excellent relative sensitivity of 15.5% K-1 based on the 4F9/2/2H11/2(2) level pair were synchronously achieved at room temperature. These findings provide a novel strategy for surmounting the thermal quenching luminescence, thereby greatly promoting the application of non-contact sensitive radiometric thermometers.

Embedding Atomically Dispersed Manganese/Gadolinium Dual Sites in Oxygen Vacancy-Enriched Biodegradable Bimetallic Silicate Nanoplatform for Potentiating Catalytic Therapy

Due to their atomically dispersed active centers, single-atom nanozymes (SAzymes) have unparalleled advantages in cancer catalytic therapy. Here, loaded with chlorin e6 (Ce6), a hydrothermally mass-produced bimetallic silicate-based nanoplatforms with atomically dispersed manganese/gadolinium (Mn/Gd) dual sites and oxygen vacancies (OVs) (PMnSA GMSNs-V@Ce6) is constructed for tumor glutathione (GSH)-triggered chemodynamic therapy (CDT) and O2 -alleviated photodynamic therapy. The band gaps of silica are significantly reduced from 2.78 to 1.88 eV by doping with metal ions, which enables it to be excited by a 650 nm laser to produce electron-hole pairs, thereby facilitating the generation of reactive oxygen species. The Gd sites can modulate the local electrons of the atom-catalyzed Mn sites, which contribute to the generation of superoxide and hydroxyl radicals (• OH). Tumor GSH-triggered Mn2+ release can convert endogenous H2 O2 to • OH and realize GSH-depletion-enhanced CDT. Significantly, the hydrothermally generated OVs can not only capture Mn and Gd atoms to form atomic sites but also can elongate and weaken the O-O bonds of H2 O2 , thereby improving the efficacy of Fenton reactions. The degraded Mn2+ /Gd3+ ions can be used as tumor-specific magnetic resonance imaging contrast agents. All the experimental results demonstrate the great potential of PMnSA GMSNs-V@Ce6 as cancer theranostic agent.

Controlling the optical and magnetic properties of CdTeSe and Gd-doped CdTeSe alloy semiconductor nanocrystals

In this study, CdTexSe1-x (0 ≤ x ≤ 1) and CdTeSe:Gd y% (y = 0-8.05) alloy semiconductor nanocrystals (NCs) were prepared by wet chemical method. The presence and composition of the elements in the sample were determined by energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). Structural analysis of X-ray diffraction (XRD) patterns indicated that most NCs crystallized in the zinc blende (ZB) structure however some Gd-doped NCs (y = 4.52 and 8.05%) crystallized in the wurtzite (WZ) structure. The emission peak of CdTexSe1-x (0 ≤ x ≤ 1) NCs varied over a wide range when changing x while the particle size remained almost unchanged. The effect of Gd doping on the structure and optical and magnetic properties of CdTeSe NCs was studied in detail. When the Gd concentration increases from 0-8.05%: (i) the structure of CdTeSe NCs gradually changed from ZB to WZ, (ii) the emission efficiency of the material was significantly reduced, (iii) the PL lifetime of samples increased more than 10 times, and (iv) the ferromagnetic properties of the material were enhanced. The research findings demonstrated that it is possible to control the crystal structure, optical characteristics, and magnetic properties of Gd-doped CdTeSe nanocrystals by adjusting the dopant concentration and chemical composition of the host material.

Microwave-assisted synthesis of GdOF: Eu3+/Tb3+ ultrafine phosphor powders suitable for advanced forensic and security ink applications

The rare-earth-doped inorganic ultrafine oxyfluoride host matrices in forensic science, especially in latent fingerprint detection and anti-counterfeiting applications, were still unexplored and may replace the existing technology owing to its high sensitivity. Herein, GdOF: Eu³⁺/Tb³⁺ ultrafine red and green phosphors were synthesized via a rapid, green microwave-assisted hydrothermal method at 150 °C. The phosphors synthesized by this novel method possess good luminescent intensity for the hypersensitive ⁵D₀→⁷F₂ transition of Eu³⁺ and ⁵D₄→⁷F₅ transition of Tb³⁺ ions as compared to the phosphors prepared via other conventional methods such as co-precipitation synthesis, sol-gel synthesis, and microwave-assisted co-precipitation synthesis. Further, an enhancement in the luminescent intensity of the ultrafine phosphor was noticed when the microwave parameters and pH values were tuned. The optimized red and green phosphors having high luminescence intensity, good color purity, and high quantum yields of 89.3%, and 71.2%, respectively, were used for the visualization of latent fingerprints on various substrates. These promising phosphors exhibited excellent visualization regardless of the background interference and limit the risk of duplication and are highly reliable. The security inks developed using these phosphors are highly efficient for anti-counterfeiting applications. These multifunctional properties of investigated phosphors can be explored for security applications.

Suppression of intrinsic thermal conductivity in Sr1-x Gd x TiO3 ceramics via phonon-point defect scattering for enhanced thermoelectric application

A substantial reduction in the thermal conductivity for strontium titanate (ABO₃) perovskite structure was realized for the A-site substitution of gadolinium (rare earth element) in SrTiO₃ ceramics. The effect of Gd³⁺ substitution on the structure, composition, and thermoelectric properties of SrTiO₃ was investigated. The substitution of Gd³⁺ in the SrTiO₃ matrix resulted in the minimalization of thermal conductivity. The thermal conductivity followed a similar trend as that of thermal diffusivity, but specific heat capacity exhibited a non-monotonic trend. The thermal conductivity is reduced to 1.05 W m^-1 K^-1 for the minimal substitutional composition (Sr_0.99Gd_0.01TiO₃) which is 30% less than that of SrTiO₃ at 303 K. The variation in the ionic radii and atomic mass of the heavier rare earth Gd³⁺ substituted over Sr²⁺ resulted in the reduction of thermal conductivity of SGTO ceramics caused by the corresponding boundary scattering at low temperatures and temperature-independent phonon-impurity scattering at high temperatures.

Fabrication of Novel and Potential Selective 4-Cyanophenol Chemical Sensor Probe Based on Cu-Doped Gd2O3 Nanofiber Materials Modified PEDOT:PSS Polymer Mixtures with Au/µ-Chip for Effective Monitoring of Environmental Contaminants from Various Water Samples

Herein, a novel copper-doped gadolinium oxide (Cu-doped Gd2O3; CGO) nanofiber was synthesized by a simple solution method in the basic phase and successfully characterized. We have used Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Energy-Dispersive Spectroscopy (EDS) techniques for characterization of the CGO nanofiber. The CGO nanofiber was used later to modify Au-coated μ-Chips with poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer mixtures (coating binder) to selectively detect 4-cyanophenol (4-CP) in an aqueous medium. Notable sensing performance was achieved with excellent sensitivity (2.4214 µAµM-1 cm-2), fast response time (~12 s), wide linear dynamic range (LDR = 1.0 nM-1.0 mM: R2 = 0.9992), ultra-low detection limit (LoD; 1.3 ± 0.1 pM at S/N = 3), limit of quantification (LoQ; 4.33 pM), and excellent reproducibility and repeatability for CGO/Au/μ-Chip sensor. This CGO modified Au/μ-chip was further applied with appropriate quantification and determination results in real environmental sample analyses.

Synthesis of Gd2O3 Nanoparticles and Their Photocatalytic Activity for Degradation of Azo Dyes

Gadolinium oxide (Gd2O3) nanoparticles were prepared via the reaction of gadolinium nitrate hexahydrate (Gd (NO3)3·6H2O) and ethylamine (C2H5NH2), and their surface morphology, particle size, and properties were examined by using scanning electron microscopy, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet visible (UV-vis) spectroscopy. The Gd2O3 nanoparticles were used as the photocatalyst for the degradation of various azo dyes, such as methyl orange (MO), acid orange 7 (AO7), and acid yellow 23 (AY23) under irradiation with UV light. The effect of the experimental parameters (initial concentration of azo dyes, dosage of catalyst, and wavelength of UV light) on the photocatalytic properties of the Gd2O3 nanoparticles were investigated. At a constant H2O2 concentration, the photocatalytic degradation efficiency of the Gd2O3 nanoparticles for various azo dyes was in the order: methyl orange > acid orange 7 > acid yellow 23. The kinetics study showed that the photocatalytic degradation of azo dyes was followed by a pseudo first-order reaction rate law.

Switching Characteristics and Mechanism Using Al2O3 Interfacial Layer in Al/Cu/GdOx/Al2O3/TiN Memristor

Resistive switching characteristics by using the Al2O3 interfacial layer in an Al/Cu/GdOx/Al2O3/TiN memristor have been enhanced as compared to the Al/Cu/GdOx/TiN structure owing to the insertion of Al2O3 layer for the first time. Polycrystalline grain, chemical composition, and surface roughness of defective GdOx film have been investigated by transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and atomic force microscopy (AFM). For bipolar resistive switching (BRS) characteristics, the conduction mechanism of high resistance state (HRS) is a space-charge limited current for the Al/Cu/GdOx/TiN device while the Al/Cu/GdOx/Al2O3/TiN device shows Schottky emission. However, both devices show Ohmic at a low resistance state (LRS). After the device has been SET, the Cu filament evidences by both TEM and elemental mapping. Oxygen-rich at the Cu/GdOx interface and Al2O3 layer are confirmed by energy dispersive X-ray spectroscopy (EDS) line profile. The Al/Cu/GdOx/Al2O3/TiN memristor has lower RESET current, higher speed operation of 100 ns, long read pulse endurance of >109 cycles, good data retention, and the memristor with a large resistance ratio of >105 is operated at a low current of 1.5 µA. The complementary resistive switching (CRS) characteristics of the Al/Cu/GdOx/Al2O3/TiN memristor show also a low current operation as compared to the Al/Cu/GdOx/TiN device (300 µA vs. 3.1 mA). The transport mechanism is the Cu ion migration and it shows Ohmic at low field and hopping at high field regions. A larger hopping distance of 1.82 nm at the Cu/GdOx interface is obtained as compared to a hopping distance of 1.14 nm in the Al2O3 layer owing to a larger Cu filament length at the Cu/GdOx interface than the Al2O3 layer. Similarly, the CRS mechanism is explained by using the schematic model. The CRS characteristics show a stable state with long endurance of >1000 cycles at a pulse width of 1 µs owing to the insertion of Al2O3 interfacial layer in the Al/Cu/GdOx/Al2O3/TiN structure.

An MRI-visible immunoadjuvant based on hollow Gd2O3 nanospheres for cancer immunotherapy

Hollow Gd2O3 nanospheres significantly promote the cellular uptake of a tumor antigen by antigen presenting cells, exhibit pH-dependent alteration of the MR signal intensity and markedly enhance the antitumor immunity. Hollow Gd2O3 nanospheres are promising as magnetic resonance imaging (MRI)-visible cancer immunoadjuvants for cancer immunotherapy.

Application of FTIR-ATR spectroscopy to confirm the microwave assisted synthesis and curing of Cashew nut shell liquid derived nanostructured materials

The present work reports the development of nanostructured material from Cashew nut shell liquid (CNSL, an agro byproduct of cashew industry, 87% cardanol) to evaluate their potential in antibacterial applications as a substitute of petroleum feedstock via an energy-efficient method. The nanostructured material was synthesized by coordination polymerization reaction of cardanol and divalent Mn(II) salt with the aid of microwave irradiations. FTIR spectroscopy was used to confirm the proposed structure of the synthesized materials. FTIR-ATR spectroscopy was employed to verify the curing of material by comparing the spectra of the cured samples with the frequencies of uncured samples. Magnetic moment and UV-visible spectroscopy were used to confirm the proposed structure of the material further. Morphology of the synthesized material was investigated by XRD, optical microscopy, SEM and TEM and thermal behaviour by TGA/DTG/DSC technique. Agar diffusion method was utilized to investigate the antibacterial activity of the synthesized material against bacterial strains E. coli, K. pneumoniae, B. subtilis and S. aureus. N₂ adsorption-desorption was investigated to check BET specific surface area and BJH pore size distribution of the same. The results revealed that the synthesized materials were obtained as semicrystalline, porous, thermally stable and nanostructured film forming materials with moderate to good antibacterial activity against different nosocomial bacteria. They can be used as thermally stable antibacterial agents in the field of films/coatings for health care applications.

HSA functionalized Gd2O3:Eu3+ nanoparticles as an MRI contrast agent and a potential luminescent probe for Fe3+, Cr3+, and Cu2+ detection in water

PVP capped Gd₂O₃:Eu³⁺ (PVP@Gd₂O₃:Eu³⁺) and HSA functionalised PVP@Gd₂O₃:Eu³⁺ (HSA@PVP@Gd₂O₃:Eu³⁺) NPs as fluorescent detection probe for metal ion detection and MRI contrast agent.

Microemulsion-made gadolinium carbonate hollow nanospheres showing magnetothermal heating and drug release

Gadolinium carbonate (Gd₂(CO₃)₃) hollow nanospheres and their suitability for drug transport and magnetothermally-induced drug release are presented. The hollow nanospheres are prepared via a microemulsion-based synthesis using tris(tetramethylcyclopentadienyl)gadolinium(iii) and CO₂ as the starting materials. Size, structure and composition of the as-prepared Gd₂(CO₃)₃ hollow nanospheres are comprehensively validated by several independent analytical methods (HRTEM, HAADF-STEM, DLS, EDXS, XRD, FT-IR, DTA-TG). Accordingly, they exhibit an outer diameter of 26 ± 4 nm, an inner cavity of 7 ± 2 nm, and a wall thickness of 9 ± 3 nm. As a conceptual study, the nanocontainer-functionality of the Gd₂(CO₃)₃ hollow nanospheres is validated upon filling with the anti-cancerogenic agent doxorubicin (DOX), which is straightforward via the microemulsion (ME) strategy. The resulting DOX@Gd₂(CO₃)₃ nanocontainers provide the option of multimodal imaging including optical and magnetic resonance imaging (OI, MRI) as well as magnetothermal heating and drug release. As a proof-of-concept, we could already prove the intrinsic DOX-based fluorescence, a low systemic toxicity according to in vitro studies as well as the magnetothermal effect and a magnetothermally-induced DOX release. In particular, the latter is new for Gd-containing nanoparticles and highly promising in view of theranostic nanocontainers and synergistic physical and chemical tumor treatment.

Europium-phenolic network coated BaGdF5 nanocomposites for tri-modal computed tomography/magnetic resonance/luminescence imaging

Multifunctional nanocomposites based on BaGdF₅ nanoparticles (NPs) and metal phenolic network (MPN) have been engineered as novel contrast agents for potential applications in X-ray computed tomography, magnetic resonance and luminescence imaging. The BaGdF₅@MPN nanocomposites were synthesized at room temperature by coating BaGdF₅ NPs with europium-phenolic network, which was obtained by the coordination of europium (III) with tannic acid (TA). The in vitro cytotoxicity assays against HepG2 cells revealed that the BaGdF₅@MPN nanocomposites presented better cytocompatibility and lower cytotoxity than pure BaGdF₅ NPs. In addition, vivid red and green luminescence can be observed by confocal laser scanning microscope (CLSM) from the BaGdF₅@MPN nanocomposites laden HepG2 cells under the excitation of UV (390 nm) and visible light (440 nm), respectively. The longitudinal relaxivity value (r₁) of the nanocomposites was 2.457 mM^-1s^-1. Moreover, the nanocomoposites exhibited X-ray computed tomography (CT) and T₁-weighted magnetic resonance (MR) imaging capacities, and the intensities of the enhanced signals of in vitro CT and MR images were proportional to the concentrations of the nanocomposites. These results indicated that the as-prepared BaGdF₅@MPN nanocomposites are promising contrast agents for CT/MR/luminescence imaging.

Surface-Engineered Multifunctional Eu:Gd2O3 Nanoplates for Targeted and pH-Responsive Drug Delivery and Imaging Applications

In this paper, we report the synthesis of surface-engineered multifunctional Eu:Gd₂O₃ triangular nanoplates with small size and uniform shape via a high-temperature solvothermal technique. Surface engineering has been performed by a one-step polyacrylate coating, followed by controlled conjugation chemistry. This creates the desired number of surface functional groups that can be used to attach folic acid as a targeting ligand on the nanoparticle surface. To specifically deliver the drug molecules in the nucleus, the folate density on the nanoparticle surface has been kept low. We have also modified the drug molecules with terminal double bond and ester linkage for the easy conjugation of nanoparticles. The nanoparticle surface was further modified with free thiols to specifically attach the modified drug molecules with a pH-responsive feature. High drug loading has been encountered for both hydrophilic drug daunorubicin (∼69% loading) and hydrophobic drug curcumin (∼75% loading) with excellent pH-responsive drug release. These nanoparticles have also been used as imaging probes in fluorescence imaging. Some preliminary experiments to evaluate their application in magnetic resonance imaging have also been explored. A detailed fluorescence imaging study has confirmed the efficient delivery of drugs to the nuclei of cancer cells with a high cytotoxic effect. Synthesized surface-engineered nanomaterials having small hydrodynamic size, excellent colloidal stability, and high drug-loading capacity, along with targeted and pH-responsive delivery of dual drugs to the cancer cells, will be potential nanobiomaterials for various biomedical applications.

Detection of pH and Enzyme-Free H2O2 Sensing Mechanism by Using GdO x Membrane in Electrolyte-Insulator-Semiconductor Structure

A 15-nm-thick GdO x membrane in an electrolyte-insulator-semiconductor (EIS) structure shows a higher pH sensitivity of 54.2 mV/pH and enzyme-free hydrogen peroxide (H2O2) detection than those of the bare SiO2 and 3-nm-thick GdO x membranes for the first time. Polycrystalline grain and higher Gd content of the thicker GdO x films are confirmed by transmission electron microscopy (TEM) and X-ray photo-electron spectroscopy (XPS), respectively. In a thicker GdO x membrane, polycrystalline grain has lower energy gap and Gd(2+) oxidation states lead to change Gd(3+) states in the presence of H2O2, which are confirmed by electron energy loss spectroscopy (EELS). The oxidation/reduction (redox) properties of thicker GdO x membrane with higher Gd content are responsible for detecting H2O2 whereas both bare SiO2 and thinner GdO x membranes do not show sensing. A low detection limit of 1 μM is obtained due to strong catalytic activity of Gd. The reference voltage shift increases with increase of the H2O2 concentration from 1 to 200 μM owing to more generation of Gd(3+) ions, and the H2O2 sensing mechanism has been explained as well.

Synthesis and Characterization of Gd₂O₃ Hollow Microspheres Using a Template-Directed Method

Uniform rare-earth gadolinium oxide (Gd₂O₃) hollow microspheres, as formed through a urea-assisted homogenous precipitation process using carbon spheres as a template and a subsequent heat treatment, were characterized by using X-ray diffraction, Fourier transformed infared spectroscopy, thermogravimetry, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and Brunauer-Emmett-Tellet surface area measurement. The results indicate that the final products can be indexed to a cubic Gd₂O₃ phase with high purity and have a uniform morphology at 500 nm in diameter and 20 nm in shell thickness. The as-synthesized Gd₂O₃ hollow microspheres exhibited a superior photooxidation activity to that of Gd₂O₃ powder and an effect similar to P25, significantly broadening the potential of Gd₂O₃ hollow microspheres for many practical applications.

Facile preparation of multifunctional uniform magnetic microspheres for T1-T2 dual modal magnetic resonance and optical imaging

Molecular imaging is of significant importance for early detection and diagnosis of cancer. Herein, a novel core-shell magnetic microsphere for dual modal magnetic resonance imaging (MRI) and optical imaging was produced by one-pot emulsifier-free emulsion polymerization, which could provide high resolution rate of histologic structure information and realize high sensitive detection at the same time. The synthesized magnetic microspheres composed of cores containing oleic acid (OA) and sodium undecylenate (NaUA) modified Fe3O4 nanoparticles and styrene (St), Glycidyl methacrylate (GMA), and polymerizable lanthanide complexes (Gd(AA)3Phen and Eu(AA)3Phen) polymerized on the surface for outer shells. Fluorescence spectra show characteristic emission peaks from Eu(3+) at 590nm and 615nm and vivid red fluorescence luminescence can be observed by 2-photon confocal scanning laser microscopy (CLSM). In vitro cytotoxicity tests based on the MTT assay demonstrate good cytocompatibility, the composites have longitudinal relaxivity value (r1) of 8.39mM(-1)s(-1) and also have transverse relaxivity value (r2) of 71.18mM(-1)s(-1) at clinical 3.0 T MR scanner. In vitro and in vivo MRI studies exhibit high signal enhancement on both T1- and T2-weighted MR images. These fascinating multifunctional properties suggest that the polymer microspheres have large clinical potential as multi-modal MRI/optical probes.

Smart polymeric particle encapsulated gadolinium oxide and europium: theranostic probes for magnetic resonance/optical imaging and antitumor drug delivery

Paramagnetic, luminescent, and temperature/pH-responsive polymeric particles with MR/optical imaging and antitumor drug delivery capability are prepared by emulsifier-free emulsion polymerization.

Energy transfer and tunable multicolor emission and paramagnetic properties of GdF3:Dy3+,Tb3+,Eu3+ phosphors

GdF₃:RE³⁺ (RE = Dy³⁺, Tb³⁺, Eu³⁺) phosphors can realize multicolor emission including white light. Simultaneously, GdF₃:RE³⁺ (RE = Dy³⁺, Tb³⁺, Eu³⁺) phosphors also exhibit paramagnetic properties at room temperature and low temperatures.

Mesoporous silica coated Gd2(CO3)3:Eu hollow nanospheres for simultaneous cell imaging and drug delivery

The efficient optical/MR imaging capabilities, and the hollow structure make Gd₂(CO₃)₃:Eu@mSiO₂ a promising platform for simultaneous bioimaging and drug delivery.

A broad spectrum photon responsive, paramagnetic β-NaGdF4:Yb3+,Er3+ – mesoporous anatase titania nanocomposite

Herein, we report a novel single multifunctional platform based on broad-spectrum photoactive β-NaGdF₄:18% Yb³⁺, 2% Er³⁺ and mesoporous anatase TiO₂ for enhanced energy and simultaneous biomedical applications.

Enhancing the dual magnetic and optical properties of co-doped cerium oxide nanostructures

Iron and europium co-doped cerium oxide nanoparticles exhibits interesting optical and magnetic properties.