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The present study emulates a one-pot facile synthesis of selenium-enriched CoSe nanotube using a chemical bath deposition (CBD) procedure. Schematic incorporation of 3D Ni foam current collectors as substrates for the growth of CoSe–Se nanotubes helped us achieve a binder-less thin film coating. The controlled synthesis of CoSe–Se nanotube was carried out by optimizing the temperature and time of the deposition. CoSe–Se nanotubes were grown on a porous Ni foam substrate using lithium chloride as a shape directing agent. The study found that the one dimensional structure of the nanotubes with porous nature results in an uninterrupted network of electroactive sites. Due to the superior conductivity, the as-fabricated material exhibited excellent rate capability and a higher degree of electrolyte ion diffusion across the CoSe–Se crystal structure. The CoSe–Se@Ni foam electrodes exhibited a specific capacitance of 1750.81 F g−1 at 1 A g−1. The electrode exhibited excellent cycling stability and showed a capacitance retention of 95% after 4000 charge-discharge cycles. Finally, an asymmetric supercapacitor (ASC) device was fabricated with the as-synthesized CoSe–Se@Ni foam electrode as the cathode, activated carbon@Ni foam electrode as the anode, and a thin filter paper separator soaked in 1 M aqueous KOH electrolyte solution. The ASC device showed a specific capacitance value of 106.73 F g−1 at 0.5 A g−1, and achieved an energy density of 37.94 Wh kg−1 at a power density of 475.30 W kg−1. The ASC device was utilized in an extended potential window of 1.6 V. The fabricated device displayed exceptional cycling stability with a capacitance retention of 93% after 5000 charge-discharge cycles.

There are ongoing efforts to develop novel phosphors with the properties required to make an object look as natural as it does under sunlight. It has been proven that particle morphology influences the luminescent properties of a phosphor. The rare-earth pyrosilicates, such as La2Si2O7 (LSO) are currently regarded as novel promising scintillators and protective pigments because of their good chemical and thermal stabilities. However, to date, there have been no reports available on the definite morphology of the LSO matrix and the precise luminescent properties of the trivalent europium (Eu3+)-doped LSO phosphor. Herein, we report the development of Eu3+-activated dumbbell-shaped LSO nanocrystalline phosphors using a two-step solvothermal and hydrothermal approach. After regrowth, the amorphous natured LSO:Eu3+ precursor was transformed into well-defined LSO:Eu3+ dumbbell-shaped nanocrystalline phosphors (LSO-R:Eu3+) with a pure monoclinic phase. The phase purity was verified by Rietveld refinement analysis. The formation mechanism of the dumbbell-shaped particles was evaluated using surface morphological studies, and the involvement of the crystal splitting mechanism was established. The luminescence spectra revealed robust red emission at 614 nm under ultraviolet (UV) and near-UV excitations. The dipole-dipole interactions between the neighboring Eu3+ ions induced the concentration quenching in LSO host matrix. Chromaticity coordinates (0.645, 0.342) emerged in the reddish-orange region and were comparable to the standard-definition and high-definition digital television coordinates (0.640, 0.330). Therefore, these results indicate that the synthesized LSO-R:Eu3+ dumbbell-shaped nanocrystalline phosphor is a promising auxiliary red component for assembling desired white light-emitting diodes for indoor illuminations.

Colorectal cancer (CRC) is one of the deadliest diseases worldwide due to a lack of early detection methods and appropriate drug delivery strategies. Conventional imaging techniques cannot accurately distinguish benign from malignant tissue, leading to frequent misdiagnosis or diagnosis at late stages of the disease. Novel screening tools with improved accuracy and diagnostic precision are thus required to reduce the mortality burden of this malignancy. Additionally, current therapeutic strategies, including radio- and chemotherapies carry adverse side effects and are limited by the development of drug resistance. Recent advances in nanotechnology have rendered it an attractive approach for designing novel clinical solutions for CRC. Nanoparticle-based formulations could assist early tumor detection and help to overcome the limitations of conventional therapies including poor aqueous solubility, nonspecific biodistribution and limited bioavailability. In this review, we shed light on various types of nanoparticles used for diagnosis and drug delivery in CRC. In addition, we will explore how these nanoparticles can improve diagnostic accuracy and promote selective drug targeting to tumor sites with increased efficiency and reduced cytotoxicity against healthy colon tissue.

Due to their unique optical properties like narrow emission bands, the applicability of fluorescent nanomaterials have recently been extended to various fields such as forensic science and urban farming. Herein, we report a novel fluorescent material of Mn4+ ions doped Ba2LaNbO6 (BLN:Mn4+) with nanorod-like morphology for latent fingerprint detection as well as plant growth light-emitting diodes (LEDs) through a facile citric acid-assisted sol-gel route. The crystallization, elemental composition and oxidation states present in the BLN:Mn4+ nanophosphors are confirmed by the X-ray diffraction and X-ray photoelectron spectroscopy analyses. The photoluminescence spectra reveal a promising red emission band at 685 nm wavelength region under both 351 and 510 nm excitations, which is the required far-red emission for phototropism in plants. Furthermore, the optimized BLN:0.25Mn4+ nanophosphors exhibited all the features required for three levels of latent fingerprint detection on various nonporous surfaces under 365 nm illumination. The fluctuation of the red value on pixel profile confirms the good affinity of BLN:0.25Mn4+ nanophosphors with the fingerprint ridges. Because of their excellent luminescent properties and brilliant performance in the latent fingerprint detection process, the synthesized BLN:Mn4+ nanophosphors can be considered as a promising fluorescent material for the fabrication of plant growth LEDs and latent fingerprint applications.

Novel hybrid decontamination processes based on visible-light-responsive photocatalysts (VLPHS) have recently become a focus of environmental research. In this study, the sonophotocatalytic degradation of the antibiotic tetracycline (TC) using a binary rGO/CdWO4 composite under simulated visible-light irradiation was demonstrated for the first time. Structural characterization confirmed that flower-like CdWO4 particles with a wolframite phase structure were successfully immobilized on the surface of the graphene oxide (GO). Subsequently, reduced GO/CdWO4 (rGO/CdWO4) VLPHS were prepared via the facile photocatalytic reduction of GO/CdWO4. A Box-Behnken design based on response surface methodology (RSM) was employed to determine the maximum efficiency of sonophotocatalytic degradation by optimizing the process parameters (pH, initial TC concentration, treatment time, and catalyst dosage). The high determination coefficients (R2 = 0.9818 and adjusted-R2 = 0.9636) indicated that the experimental values fitted the proposed RSM model well. Compared with CdWO4, rGO/CdWO4 VLPHS exhibited significant photoelectrochemical (PEC) performance, superior sonophotocatalytic activity, and mineralization efficiency. The enhanced catalytic activity was mainly due to the larger optical adsorption range, greater photo-induced charge carrier transfer, and higher surface area. In addition, rGO/CdWO4 exhibited a catalytic activity that was 1.5 and 3 times higher than that of commercial nano–ZnO and –TiO2, respectively. The kinetic analysis indicated that the degradation rate of TC follows the Langmuir–Hinshelwood kinetic model. The possible photocatalytic mechanism behind the degradation of TC by rGO/CdWO4 was also tentatively proposed. This study provides a simple and scalable pathway to produce highly efficient rGO-based VLPHS for photocatalytic and PEC applications.

The morphology and structural defects of nanocrystalline photocatalysts (NCPHCs) play a pivotal role in their catalytic features. Herein, various morphologies of nickel molybdate (NiMoO4) NCPHCs were synthesized via a hydrothermal route in the presence of various shape controllers (SCs) followed by a calcination process. The SCs including β-cyclodextrin (β-CD), Tween 20, ethylenediaminetetraacetic acid, and sodium dodecyl sulfate led to the formation of the rod, urchin, sphere, and flake-like morphologies of NiMoO4, respectively. X-ray diffraction, Raman, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy results corroborated a pure phase of monoclinic crystal structure of NiMoO4 by utilizing the SCs in the reaction medium, whereas the SC-free NiMoO4 demonstrated the mixed α- and β-phases. To investigate the effect of morphology on the photocatalytic activity of NiMoO4 NCPHCs, the photocatalytic decolorization of Everzol Yellow 4GL, a bio-resistant azo dye as a model pollutant, was conducted under simulated solar-light irradiation. β-CD-assisted NiMoO4 rod-like NCPHC resulted in a 2-fold higher photocatalytic activity in comparison to the other fabricated morphologies and also a 1.5-fold higher photocatalytic efficiency than that of a commercial nano-ZnO, that can be attributed to the greater availability of hydroxyl functional groups and defects in the crystalline structure. Moreover, the photo-decolorization rate was assessed by first-order, second-order, parabolic-diffusion, and modified-Freundlich kinetic models. Consequently, the result proved that photocatalytic performance is highly depends on the morphology and crystalline-phase of the NCPHCs.

Energy conservation and environmental safety are the key requirements in the modern world. We report novel orange-emitting double perovskite Ba2LaNbO6:Eu3+ (BLN:Eu3+) nanophosphor fabricated using a citrate sol-gel method for use in general illumination and photocatalysis. After annealing at 800 ℃, the particles exhibited a nanorod-like morphology with monoclinic structure. The photoluminescence emission spectra exhibited an intense 5D0→7F1 transition at 594 nm and a moderate 5D0→7F2 transition at 615 nm, demonstrating that the Eu3+ ions occupied the La3+ sites with inversion symmetry. The optimal concentration of Eu3+ ions was found to be about 5 mol% for the BLN host lattice. Energy transfer from the NbO67- octahedrons to the Eu3+ ions was clearly witnessed when the BLN:Eu3+ nanophosphors were excited with both the characteristic excitation bands of Eu3+ (7F0→5L6) and NbO67- octahedrons at 392 and 380 nm, respectively. The thermal quenching temperature of 5 mol% Eu3+ ions doped BLN nanophosphors was found to be 183 ℃, indicating that these nanophosphors are very stable at high temperatures. In addition, the dye removal efficiency of the proposed BLN nanophosphors was verified using Rhodamine B (RhB) dye as a model pollutant under UV irradiation. Compared to a commercial nano-ZnO catalyst, our synthesized BLN nanophosphors showed superior RhB de-colorization efficiency. Therefore, the proposed BLN:Eu3+ nanophosphors are promising multifunctional materials for photocatalysis and general lighting applications.

The demand for battery-type materials having hierarchical architectures, large surface areas, and excellent redox properties, to develop high energy density asymmetric supercapacitors (ASCs), is increasing. Herein, a facile single-step wet chemical method is proposed, which allows an engineered combination of α-NiMoO4 hierarchical heterostructures to be used as advanced battery-type electrodes for ASCs. The as-synthesized architectures consist of versatile nanogeometries including nanowires, nanosheets, and nanoparticles in the form of Rhynchostylis retusa-like heterostructures, which synergistically enhance the energy storage properties; specifically, at a current density of 2 A g−1, heterostructured α-NiMoO4 exhibits a superior specific capacitance of 1061 F g−1 and an outstanding cycling stability of 96%. Moreover, an aqueous ASC is fabricated by combining such a redox-type α-NiMoO4 heterostructure and activated porous carbon as the positive and negative electrodes, respectively, separated with a piece of filter paper. This device shows high energy and power densities (31.8 W h kg−1 and 786.5 W kg−1, respectively), which are useful to operate various portable electronic appliances. Together with the excellent cycling stability and energy storage properties, the synthesized heterostructured metal molybdates exemplify a new approach to develop novel electrode materials for high-performance aqueous ASCs.

Recently, organic–inorganic hybrid structures have gained significant interest and are considered as an innovative alternative for the development of multifunctional materials. Herein, we report highly reliable and reproducible protein–inorganic hybrid CaMoO4:Eu3+ microstructures as a novel photocatalyst for decontamination of environments using an energy-efficient and cost-effective green synthesis. In this synthesis process, streptavidin (SA) serves as an organic scaffold and builds covalent bonds with the amine groups of the CaMoO4:Eu3+ surface, which leads to the formation of membrane-bound-like structures. Because of the well overlapped absorption bands of tyrosine residues and CaMoO4:Eu3+, SA acts as a sensitizer and transfers more UV energy to the MoO4 moieties of CaMoO4:Eu3+, resulting in an enhanced emission intensity along with a blue shifted absorption spectrum. Compared to the commercial TiO2, the CaMoO4:Eu3+ host and SA modified CaMoO4:Eu3+ microstructures exhibit 145 and 207% higher dye removal efficiencies for methylene blue, signifying their light absorption efficiency and higher number of surface-active sites. After hybridization with SA, the CaMoO4:Eu3+ sample offers more photo-generated electrons to improve the photocatalytic activity along with an enhanced photocurrent density of 0.72 μA cm−2, which is about 1.5 times higher than that of the CaMoO4:Eu3+ host. Moreover, the SA modified CaMoO4:Eu3+ sample displayed excellent photocatalytic stability after 6 reusability cycles. Our synthesis strategy for protein–inorganic hybrid CaMoO4:Eu3+ opens a new avenue for the production of cutting-edge materials for industrial-scale catalysis and solid-state lighting applications.

Selenium-enriched nickel selenide (NiSe-Se) nanotubes supported on highly conductive nickel foam (NiSe-Se@Ni foam) were synthesized using chemical bath deposition with the aid of lithium chloride as a shape-directing agent. The uniformly grown NiSe-Se@Ni foam, with its large number of electroactive sites, facilitated rapid diffusion and charge transport. The NiSe-Se@Ni foam electrode exhibited a superior specific capacitance value of 2447.46 F g

The Gastric cancer (GC) is the third deadliest malignant disease worldwide. The most common conventional therapies include the use of anticancer drugs; however, their use is ineffective and is limited due to the poor solubility of the drug and its ability to damage the immune system, since anticancer drugs have a small therapeutic drug, overdosing can lead to the toxicity in the systemic organs such as lung, liver and kidneys. Nanotechnology, which has been developed about a decade ago is considered to be a more advantageous therapy compared to the conventional methods for the therapy of cancers like GC. Varied type of nanoparticles that are multifunctional are now used to enhance the solubility and effectiveness of the drug for the treatment, prevention and diagnosis with the annual clinical trials. Moreover, they are biocompatible and less toxic to the normal healthy cells. The organic and inorganic nanoparticles that are used in the cancer diagnosis and drug delivery system include lipid, protein, metal and polymer-based materials. This chapter gives an overview on the types of nanoparticle used in the research for the GC therapy. Additionally, we have briefly described the combinational approaches, including gene therapy and immunotherapy, along with nanoparticles that includes antibody mediated, enzyme and ligand mediated strategies.

Upconversion Sr2(Gd.98-xEr.02Ybx)8Si6O26 (SGSO:2Er3+/xYb3+) phosphor materials were synthesized using a citrate sol-gel process. X-ray diffraction patterns confirmed their hexagonal structure. Field emission scanning electron microscopy images of SGSO:2Er3+/xYb3+ phosphors depicted submicron particles. The enhanced upconversion luminescence properties of SGSO:2Er3+/xYb3+ phosphors were analysed as a function of Yb3+ ion concentration and laser power. The energy transfer induced enhanced emission of the Er3+/ Yb3+ ions co-doped SGSO phosphors was ascribed to multi-phonon relaxation. The calculated chromaticity coordinates of the SGSO:2Er3+/xYb3+ phosphors showed emissions could be tuned by changing Yb3+ ion concentration. Optimized sample exhibited the chromaticity coordinate values near to the ultra-high definition television standard green emission coordinates.

Fluorescence intensity ratio (FIR)-based optical thermometry has attracted a great deal of attention because it allows accurate and reliable temperature measurements with high spatial resolution and real-time monitoring. Herein, we report the novel Sr2Gd8(SiO4)6O2:Er3+ (SGSO:Er3+) phosphor as an optical thermometry material. The sol-gel method is used to synthesize the oxyapatite structured SGSO:Er3+ phosphors, which exhibits a rod-like morphology. The photoluminescence spectra of SGSO:Er3+ phosphors displays two distinct green emission bands corresponding to the electronic transitions 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2. The temperature-induced variations in the FIR result in a maximum sensitivity of 3.4 × 10−3 K−1 at 463 K. Further, the CIE chromaticity coordinates do not shift from the green region when the temperature is increased from 303 to 483 K and the color purity only decreasing from 77.6 to 71.4%. The SGSO:2Er3+ phosphor exhibits the color-purity of 93.5% when excited with low-energy electron beam. These results suggest that the SGSO:2Er3+ phosphor is a promising material for optical temperature sensors and display devices.

Autophagy is a conserved catabolic process involving large protein degradation by a ubiquitous autophagosomic signaling pathway, which is essential for cellular homeostasis. It is triggered by environmental factors such as stress, lack of nutrients, inflammation, and eliminating intracellular pathogens. Although the mechanisms underlying autophagy are still unclear, increasing evidence illuminates the magnitude of autophagy in a wide range of physiological processes and human diseases. Simultaneously, research community has focused on the triggering of autophagy by the internalization of engineered nanomaterials, which indicates a new line of revolution in cancer cure. However, most studies on nanoparticle-induced autophagy focus on brain, breast, and cervical cancers; limited reports are available on gastrointestinal (GI) cancers. Therefore, the aim of this mini review is to discuss in detail the role of autophagy in GI malignancy and the status of research on nanoparticle-induced autophagy.

Since the commercialization of white light-emitting diodes (WLEDs) in 1996, they are rapidly replacing conventional lighting sources and have become an essential commodity for day-to-day human life. At present, most of the WLEDs existing in the market are rare-earth based, which are very limited, expensive and often not available due to monopolistic supply conditions. Hence, there is a serious demand for novel rare-earth free phosphors to achieve cost-effective and energy-efficient WLEDs with excellent luminous efficacy for general illumination. Herein we report on highly efficient rare-earth free Cs(1−x)RbxVO3 phosphors as a single emitting compound for near UV-based WLEDs manufactured by the citrate sol–gel method for the first time. Rietveld refinement is performed for the X-ray diffraction patterns of the CsVO3 host and CsVO3:0.25Rb phosphors to reveal their orthorhombic pyroxene structure. The difference in the ionic radii of Rb+ and Cs+ ions led to a more distorted VO43− tetrahedron with a broken Td symmetry, which allows spin forbidden transitions for CsVO3:0.25Rb phosphors, resulting in enhanced internal and external quantum efficiencies of 94.7% and 84.5% along with superior luminescence properties compared to the CsVO3 host. When varying the input current from 20 to 200 mA, the fabricated WLED exhibited a good color rendering index of 69.7–81.5 and an extremely high luminous efficacy of 94.8–58.7 lm W−1, which are among the highest values for the same host lattice. These rare-earth free CsVO3:0.25Rb phosphors with a single emitting center may emerge as a new class of advanced inorganic phosphors for near UV-based WLEDs in the lighting industries.

Evolution of a simple, efficient and reproducible strategy for the rational design of hierarchically structured metal chalcogenide-based supercapacitors has attracted considerable research interest in recent years. Herein, a facile wet-chemistry approach is employed to design three-dimensional forest-like porous nickel sulfide nanotrees on nickel foam (NiS NTs/Ni foam) for use as a cathode material in hybrid supercapacitors. The growth time plays a crucial role in controlling the surface morphology, and the optimal growth conditions (3 h at 85 °C) led to the growth of forest-like NiS NTs/Ni foam with reliable adherence. The forest-like NiS NTs/Ni foam shows maximum areal and specific capacities of 752.71 μA h cm−2 and 342.1 mA h g−1 at a current density of 4 mA cm−2, with an excellent cycling stability of 89.4%. This result is primarily due to the availability of more surface-active sites in the well-defined hierarchical architecture, which allow the rapid diffusion of electrolyte ions and minimize the electron transport limitation. Utilizing the hierarchical NiS NTs/Ni foam as a cathode and activated carbon-based anode, we further fabricated a hybrid supercapacitor, which demonstrates a wide potential window of 1.6 V with high areal energy and power densities of 0.472 mW h cm−2 and 21.5 mW cm−2, respectively. The fabricated hybrid supercapacitor is successfully utilized to drive various electronic gadgets for real-life applications. The electrochemical performance of a hierarchically structured NiS-based binder-free electrode with our facile approach paves a new pathway for the development of novel metal chalcogenides for high-performance hybrid supercapacitors.

We report a facile and large-scale synthesis of size-tunable and nontoxic mesoporous silica-coated Gd2O3:Eu3+ (Gd@mSi) core–shell nanostructures using a TPAOH assisted modified UHP technique. The role of TPAOH in controlling the particle size was evaluated. The potentiality of these Gd@mSi core–shell nanoparticles before and after folic acid conjugation was established by in vitro fluorescence microscopy of the U2OS cell lines for cancer imaging and therapy.

At present, phosphor-converted white light-emitting diodes (pc-WLEDs), developed by combining an ultraviolet (UV)/near-UV (NUV) LED and a single-component white emitting phosphor, have attracted significant interest and are emerged as the new-generation green light sources. Herein, we report a highly photostable and novel Gd2TiO5 (GT):Dy3+/Eu3+ nanophosphors as single-component white emitting phosphors by sol-gel route. Based on X-ray diffraction pattern, Rietveld refinement is performed to authorize the orthorhombic phase of the GT nanophosphors. The nanosized particles with nearly spherical morphology is perceived after annealing at 1100 ℃. The Dy3+ and Eu3+ ions individually-doped GT nanophosphors exhibited pleasant white and reddish-orange emissions by monitoring with their respective excitation wavelengths. Tunable white light emission is achieved by co-doping the various concentrations of Eu3+ ions to the optimized GT:1.5Dy3+ nanophosphors under both UV (270 nm) and NUV (362 nm) excitations. The energy transfer probability is discussed and the energy transfer efficiency from Dy3+ to Eu3+ ions is calculated from the luminescence decay profiles. On rising the Eu3+ ions content from 0.25 to 6 mol%, the energy transfer efficiency is increased from 14% to 73% for co-doped GT nanophosphors. Besides, the optimized samples of Dy3+ and Eu3+ ions individually-doped and co-doped GT samples exhibited high quantum efficiencies and increased photostability. Thus, the acquired results signifying that these GT:Dy3+/Eu3+ nanophosphors can serve as potential single-component white emitting phosphors for UV and/or NUV-based pc-WLEDs.

To meet the requirements of warm white light-emitting diodes (WLEDs) with extreme thermal stability, high color rendering index and low color temperature, which is equivalent to natural sunlight, we need to develop novel phosphor materials that can efficiently absorb excitation energy from near-ultraviolet (NUV) LEDs and produce desired visible emissions. The Sr 2+ and Eu 2+ ions co-activated Ba 2 SiO 4 ((BaSr)Si:Eu 2+ ) green-emitting nanophopshors for NUV or blue excitation-based WLEDs are reported. After annealing at 1300 °C, the X-ray diffraction patterns established the pure orthorhombic phase of (BaSr)Si:Eu 2+ nanophosphors. The evolution of (BaSr)Si:Eu 2+ nanorods from the surface of the sub-micron sized (BaSr)Si:Eu 2+ particles showed a tremendous effect on the luminescent properties by enhancing the transmittance of the (BaSr)Si:Eu 2+ nanophosphor. The incorporation of Sr 2+ ions along with Eu 2+ ions into the Ba 2+ sites, the emission intensity was increased, and also the quantum efficiency was enhanced from 47 to 59%. Upon excitation at 370 nm, the Ba 2 SiO 4 :Eu 2+ phosphor exhibited a bluish-green emission while the yellowish-green emission was revealed by the (BaSr)Si:Eu 2+ nanophosphor. The thermal stability of the (BaSr)Si:Eu 2+ nanophosphor was verified at elevated temperatures and the activation energy for thermal quenching was found to be 0.38 eV. When the (BaSr)Si:Eu 2+ nanophosphor was coated on a NUV LED chip, the enriched green emission was observed by increasing the input current from 100 to 250 mA. The (BaSr)Si:Eu 2+ is expected to be a promising green-emitting phosphor material for the fabrication of NUV or blue excitation-based warm WLEDs for general illumination.

Nanostructured inorganic materials are potential building blocks for advanced materials and devices with desired functions. Latent fingerprint technology requires cost-effective and high-quality luminescent nanomaterials to identify an individual with sufficient information. We report the synthesis and growth mechanism of novel nanostructured CaGd2ZnO3(CO3)2·H2O and CaGd2ZnO5 materials through a urea- and EDTA-mediated hydrothermal process. The conversion from the carbonate to the oxide form is explained using physicochemical measurements. Furthermore, when doped with Eu3+ ions, CaGd2ZnO5 nanostructures exhibit superior luminescent properties to replace conventional red phosphors for latent fingerprint technology. In contrast to previously reported individual fluorescent nanoparticles, CaGd2ZnO5:5Eu3+ nanostructures provide three levels of identification with high-quality imaging on various hydrophilic and hydrophobic substrates. These properties demonstrate that CaGd2ZnO5:Eu3+ nanorod bundles are a promising luminescent material for solid-state lighting and latent fingerprint technologies.

Female-specific cancers are the most common cancers in women worldwide. Early detection methods remain unavailable for most of these cancers, signifying that most of them are diagnosed at later stages. Furthermore, current treatment options for most female-specific cancers are surgery, radiation and chemotherapy. Although important milestones in molecularly targeted approaches have been achieved lately, current therapeutic strategies for female-specific cancers remain limited, ineffective and plagued by the emergence of chemoresistance, which aggravates prognosis. Recently, the application of nanotechnology to the medical field has allowed the development of novel nano-based approaches for the management and treatment of cancers, including female-specific cancers. These approaches promise to improve patient survival rates by reducing side effects, enabling selective delivery of drugs to tumor tissues and enhancing the uptake of therapeutic compounds, thus increasing anti-tumor activity. In this review, we focus on the application of nano-based technologies to the design of novel and innovative diagnostic and therapeutic strategies in the context of female-specific cancers, highlighting their potential uses and limitations.

Cancer theranostics represents a strategy that aims at combining diagnosis with therapy through the simultaneous imaging and targeted delivery of therapeutics to cancer cells. Recently, the folate receptor alpha has emerged as an attractive theranostic target due to its overexpression in multiple solid tumors and its great functional versatility. In fact, it can be incorporated into folate-conjugated nano-systems for imaging and drug delivery. Hence, it can be used along the line of personalized clinical strategies as both an imaging tool and a delivery method ensuring the selective transport of treatments to tumor cells, thus highlighting its theranostic qualities. In this review, we will explore these theranostic characteristics in detail and assess their clinical potential. We will also discuss the technological advances that have allowed the design of sophisticated folate-based nanocarriers harboring various chemical properties and suited for the transport of various therapeutic agents.

The glycoprotein FRα is a membrane-attached transport protein that is shielded from the immune system in healthy cells. However, it is upregulated in various malignancies, involved in cancer development and is also immunogenic. Furthermore, FRα is a tumor-associated antigen endowed with unique properties, thus rendering it a suitable target for immunotherapeutic development in cancer. Various anti- FRα immunotherapeutic strategies are thus currently being developed and clinically assessed for the treatment of various solid tumors. These approaches include passive anti-FRα immunotherapies, such as monoclonal antibodies, or active immunotherapies, such as CART, folate haptens and vaccines. In this review, we will explore the advances in the field of FRα-based immune therapies and discuss both their successes and shortcomings in the clinical setting.

Tb 3+ ions activated Ba 4 La 6 O(SiO 4 ) 6 (BLSO:Tb 3+ ) phosphors were synthesized by a citrate sol-gel method. The X-ray diffraction pattern confirmed their oxyapatite structure. The field-emission scanning electron microscope image established that the BLSO:Tb 3+ phosphor particles were closely-packed and acquired irregular shapes. The photoluminescence (PL) excitation spectra of BLSO:Tb 3+ phosphors showed intense f–d transitions along with low intense peaks corresponding to the f–f transitions of Tb 3+ ions in the lower energy region. The PL emission spectra displayed the characteristic emission bands of Tb 3+ ions, and the optimized concentrations were found to be at 1 and 6 mol% for blue and green emission peaks, respectively. The cathodoluminescece (CL) spectra exhibited a similar behavior that was observed in the PL spectra except the intensity variations in the blue and green regions. The CL spectra of the BLSO:6 mol% Tb 3+ phosphor unveiled accelerating voltage induced luminescent properties.

Single, double and triple trivalent rare-earth (RE3+ = Dy3+, Tm3+, Tm3+/Dy3+ and Tm3+/Dy3+/Eu3+) ions activated Sr2Gd8(SiO4)6O2 (SGSO) phosphors were synthesized by a sol–gel process. X-ray diffraction profiles confirmed their oxyapatite structure after annealing at 1450 °C for 12 h. Morphological studies were performed by taking scanning and transmission electron microscopy images, which displayed rod-like shapes. SGSO phosphors exhibited good photoluminescence (PL) properties in the respective regions when doped with Dy3+ and Tm3+ ions. Dy3+ co-activated SGSO:Tm3+ phosphors revealed tunable emissions from cool white light to warm white light towards the yellow region based on the co-activator concentration. However, Eu3+ ions co-doped SGSO:Tm3+/Dy3+ phosphors tuned the emissions towards the red region. The energy transfers from Tm3+ to Dy3+ ions and Tm3+/Dy3+ to Eu3+ ions were established based on the energy level diagram. The cathodoluminescence properties of these phosphors showed excellent emission behavior when the single, double or triple trivalent RE ions were doped into the SGSO host lattice. Unlike the case of the PL, the energy transfer process was observed to take place. The calculated Commission Internationale de l'Eclairage chromaticity coordinates of Tm3+ and Dy3+ individual ion doped SGSO phosphors confirmed the blue and white emissions, while the co-doped samples exhibited tunable emissions.

A series of Eu3+ ions activated Ba4La6(SiO4)6O (BLSO:Eu3+) phosphors were synthesized by a modified citrate sol–gel process. The structural properties of these phosphors were explored by means of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy. The XRD patterns confirmed their oxyapatite structure with the space group of P63/m after annealing at 1400 °C. The scanning electron microscope image exhibited the irregular morphology of BLSO:Eu3+ particles and the elemental mapping confirmed that the Eu3+ ions were distributed homogeneously on the La3+ ion sites. Photoluminescence (PL) excitation spectra of BLSO:Eu3+ exhibited the charge transfer band (CTB) and intense f–f transitions of Eu3+ ions in the violet and blue wavelength regions. The CTB intensity decreased and the f–f transition of Eu3+ ions increased with increasing the Eu3+ ion concentration due to the presence of defects in the 4f and 6h sites of the BLSO host lattice. This feature facilitates the strong absorption in the near-ultraviolet (NUV) region, which is useful for high color rendering index NUV based white light-emitting diodes for display and lighting applications. The PL spectra displayed intense red emission (5D0 → 7F2) along with considerable orange emission (5D0 → 7F1) with good asymmetry ratios and chromaticity coordinates, and exhibited better emission performance than that of commercial Y2O3:Eu3+ phosphors. The three-dimensional PL spectra revealed their strong emission characteristics under UV, NUV and visible excitation wavelengths. The cathodoluminescence properties were also similar to the PL results, confirming that the BLSO:Eu3+ phosphors emit stable red emission under different excitation sources as compared to the commercial Y2O3:Eu3+ phosphors.

Rare-earth niobate compounds are excellent nonlinear optical materials. Unlike other niobate materials, gadolinium ortho-niobate (GdNbO4) is reported to be inert in the visible region. The synthesis of pure-phase GdNbO4 with a definite morphology suitable for biomedical applications is still a great challenge. In this study, a novel strategy is introduced to successfully facilitate the bioavailability of GdNbO4:Eu3+ luminescent material by harnessing the pre-ouzo effect during the synthesis of mesoporous GdNbO4:Eu3+ nanospheroids. Because of the materialization of GdNbO4 nanodomains, the mesoporous GdNbO4 nanospheroids exhibit paramagnetic behaviour and allows the strong broadband excitation between 300 and 500 nm, which permits NbO6 emissions to be obtained in the visible region, whereas Eu3+ activated mesoporous GdNbO4 nanospheroids produce an intense red emission under UV, near-UV and visible excitations. These mesoporous nanospheroids also demonstrate excellent cellular internalization for HCT116 and SW680 colon cancer cells and work in conjunction with optical and magnetic resonance imaging for the accurate diagnosis and prognosis of anatomical and physiological functions. The conjugation of chlorin e6 with mesoporous GdNbO4:Eu3+ nanospheroids leads to efficient photodynamic therapy (PDT) in cancer treatment. Ultimately, our approach represents an advance in the use of mesoporous GdNbO4:Eu3+ nanospheroids as multifunctional nanoprobes for multimodal imaging and PDT.

A series of Dy3+ ions activated CaGd2ZnO5 (CGZO) nanophosphors were synthesized by a modified citrate sol–gel method. The X-ray diffraction pattern confirmed their orthorhombic structure. The field-emission scanning electron microscope images established that the CGZO particles acquired irregular shapes within the nanometer range. The photoluminescence (PL) excitation spectra of CGZO:Dy3+ showed a strong host absorption band along with low intense peaks corresponding to the f–f transitions of Dy3+ ions, indicating that efficient energy transfer occurred between the CGZO host lattice and Dy3+ ions. The PL emission spectra exhibited the characteristic emission bands of Dy3+ ions (4F9/2→6H15/2 at 486 nm and 4F9/2→6H13/2 at 572 nm) with high intense yellow emission and the optimized concentration was found to be 1 mol% in this CGZO host lattice. The cathodoluminescence spectra also showed a similar behavior that observed in the PL spectra and the emission intensities of the CGZO:1Dy3+ nanophosphor increased continuously with increasing the accelerating voltage and filament current. These novel nanophosphors are expected to have potential applications in the fields of optical displays and field-emission display systems.

GdPO 4 :Eu 3+ nanorods (~20 nm) were synthesized by a facile hydrothermal technique based on the water/2-PrOH interface. The size of nanorods was controlled by varying the reaction temperature and solvent interface. After calcination at 700 °C, the hexagonal phase of as-prepared GdPO 4 ·H 2 O:Eu 3+ nanorods was transformed into the monoclinic phase, which was confirmed by XRD patterns and TEM images. During the calcination process, along with the phase transformation, the size of nanorods was also shortened by the removal of H 2 O molecules from the lattice. Photoluminescence (PL) excitation spectra revealed the efficient energy transfer between Gd 3+ and Eu 3+ ions and the orange-red emission was typically observed from PL spectra because the Eu 3+ ions exist with inversion symmetry in the lattice. Also, these GdPO 4 :Eu 3+ nanorods were highly dispersible in water.

Green color-emitting novel CaGd2ZnO5:Tb3+ (CGZO:Tb3+) nanophosphors were synthesized by a citrate sol–gel method. The structural and morphological properties were elucidated by X-ray diffraction and transmission electron microscope measurements. The photoluminescence properties of orthorhombic-phased CGZO:Tb3+ nanophosphors were studied as a function of Tb3+ ion concentration. The CGZO:Tb3+ nanophosphors revealed the enhanced broadband excitation between ultraviolet (UV)-B and UV-A regions. Under 317 nm excitation, even at dilute Tb3+ ion concentrations, only the emission transitions from 5D4 energy level were exhibited. This unusual behavior is due to the occurrence of nonradiative energy transfer via f–d transition rather than cross-relaxation process. The cathodoluminescence also showed similar behavior at low accelerating voltages. These luminescent powders are expected to find potential applications such as white light-emitting diodes and optical display systems.

Although much progress has been made in treating cancers, cancer death rates in and around the United States are still high. Current treatments are either ineffective against some cancers or detrimental to patients, which decreases their quality of life. The use of nanotechnology in cancer therapy can potentially increase patient survival, reduce side effects, and reduce mortality rates because nanoparticles (NPs) have the potential to target only tumors and bypass healthy cells. NPs possess many features, including size, shape, charge, and composition, which allow them to carry chemotherapeutics to cancer cells. NPs can also be used in radiotherapy as radiosensitizers and in imaging as contrast agents. Many studies have performed in vitro and/or in vivo experiments on these particles in human and animal cell lines. This review discusses recent studies on different NPs and their potential use in cancer therapy.

Oriented attachment assisted self-assembled three-dimensional (3D) flower-like La(OH)3:Eu3+ nanorod bundles were successfully synthesized by a facile wet-chemical method. Hexamethylenetetramine played an important role in the formation of the hexagonal phase of La(OH)3:Eu3+ with respect to the reaction time and its concentration. No other surfactants or capping agents were used. The calcination temperature did not show any influence on the morphological texture, and the La2O3:Eu3+ phase was obtained by a subsequent annealing process. The phase formation and morphological properties were confirmed by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The photoluminescence properties were studied for both the synthesized La(OH)3:Eu3+ and La2O3:Eu3+ samples, and also compared with that of the solid-state reaction based La2O3:Eu3+ phosphor. The 3D flower-like La2O3:Eu3+ nanorod bundles showed an intense red emission due to the hypersensitive 5D0 → 7F2 transition with good asymmetric ratio and chromaticity coordinates. Likewise, a systematic study of the cathodoluminescence (CL) properties was carried out in detail. Furthermore, to estimate the CL potentiality, the La2O3:Eu3+ phosphor was compared with a commercially available Y2O3:Eu3+ red phosphor.

Red color-emitting CaGd2ZnO5:Eu3+ (CGZO:Eu3+) nanophosphors were synthesized by a facile sol–gel process. The structural and luminescent properties of these phosphors were investigated as a function of annealing temperature and Eu3+ ion concentration. The orthorhombic phase was confirmed at different annealing temperatures, showing an irregular morphology within the nanoscale range. Photoluminescence (PL) excitation spectra of CGZO:Eu3+ showed host absorption band (HAB), charge transfer band (CTB), and intense f–f transitions of Eu3+ in the violet and blue wavelength regions. The CTB intensity increased and the HAB intensity decreased with increasing annealing temperature or Eu3+ ion concentration. The CGZO:Eu3+ exhibited a strong absorption in the blue region as compared to the CTB and had a superior property compared to available commercial phosphors. This feature facilitates the fabrication of high color rendering index white light-emitting diodes for display systems. In PL spectra, an intense red emission was observed due to the hypersensitive 5D0→7F2 transition with good asymmetry ratio and chromaticity coordinates. Optimized annealing temperature and concentration of Eu3+ ions were observed for CGZO host lattice based on the 466 nm excitation wavelength. The cathodoluminescent properties were also similar to the PL results.

Er 3+ ions single-doped, Dy 3+ /Er 3+ ions co-doped, and Er 3+ /Dy 3+ /Sm 3+ ions triple-doped SrY 2 O 4 nanocrystalline phosphors were synthesized by a citrate sol–gel method. X-ray diffraction patterns confirmed their pure orthorhombic structure after annealed at 1300 °C and the morphology of particles was found to be nearly spherical. The Er 3+ ions single-doped phosphor samples showed an intense green emission band around 548 nm and the concentration quenching occurred at dilute concentrations (1 mol%) because the 4 S 3/2 energy state of Er 3+ ions can be easily quenched by means of cross relaxation to a metastable state. The Dy 3+ /Er 3+ ions co-doped phosphors exhibited a classic yellowish green emission due to efficient energy transfer from Dy 3+ to Er 3+ ions under 365 nm excitation. By adding a series of Sm 3+ ions to the Dy 3+ /Er 3+ ions co-doped SrY 2 O 4 phosphors, a pleasant white light emission which is essential for white light-emitting diodes was obtained. Likewise, from the cathodoluminescence measurements, a warm white light emission that is required for field-emission displays was achieved with accelerating voltage of 5 kV and filament current of 55 μA. A possible energy transfer mechanism was discussed and the energy transfer efficiencies were also calculated.

A series of Dy3+ ion single-doped and Dy3+/Eu3+ ion co-doped white-light emitting SrY2O4 nanocrystalline phosphors were synthesized by a citrate sol–gel method. After the samples were annealed at 1300 °C, the X-ray diffraction patterns confirmed their orthorhombic structure. The particles were closely-packed and their optical properties were monitored by photoluminescence spectroscopy. The Dy3+ ions acted as luminescent centers and substituted Y3+ ions in the SrY2O4 host lattice, where they are located in Cs sites, and the characteristic emission of Dy3+ ions (4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions) with intense yellow emission band at 578 nm occurred. When the Eu3+ ions were co-doped into the SrY2O4:Dy3+ (1 mol%) nanocrystalline phosphor, white-light emission was observed under excitation at 381 nm. The energy transfer between Eu3+ and Dy3+ ions was calculated and the chromaticity coordinates were also presented. The cathodoluminescence (CL) spectra confirmed that the penetration depth is inversely proportional to the total atomic weight and atomic number of the compound. From CL analysis, the emission intensities of Dy3+ ion single-doped and Dy3+/Eu3+ co-doped SrY2O4 nanocrystalline phosphors increased continuously upon increasing both the accelerating voltage from 1 to 5 kV and the filament current from 30 to 47 μA.

Mesoporous particles are emerging as multifunctional biomaterials for imaging and drug delivery in several disease models, including cancer. We developed PEGylated α-Gd2(MoO4)3 marigold flower-like mesoporous particles for the purpose of drug delivery and, more specifically, evaluated their ability to deliver curcumin. The obtained mesoporous particles significantly conjugated the curcumin particles on their surfaces by inducing the formation of curcumin nanoparticles. In vitro studies of the PEGylated mesoporous particles filled with curcumin demonstrated that these particles could considerably facilitate the continuous and sustained release of curcumin into the cytoplasm and nucleus. As a result, the intracellular release of curcumin can inhibit proliferation in two human pancreatic cancer cell lines: MIA PaCa-2 and PANC-1. Additionally, the particles showed the increased inhibition of pIKKα, pIKKα/β and NF-κB-DNA binding activity as compared to pure curcumin. The curcumin conjugated mesoporous particles are concentrated in the cytoplasm and nucleus of the treated cancer cell lines. Consequently, these mesoporous particles are an effective method for drug delivery that can cross the biological barriers of the body targeting the cellular nucleoplasm.

Marigold flower-like monoclinic (α)-Gd2(MoO4)3 particles with PEGylation are prepared by regrowth technology using solvothermal and hydrothermal methods. The growth mechanism of the flower-like morphology has been explained by taking SEM images of the intermediate products. SEM images of the calcined products displayed their visible pores and confirmed the stability of flower-like texture. PEGylation of α-Gd2(MoO4)3 and stability of PEG in the complex system have been verified by means of Fourier transform infrared spectra and X-ray diffraction patterns. The nitrogen adsorption–desorption isotherms of PEGylated α-Gd2(MoO4)3 particles established their mesoporous nature, and these mesoporous particles exhibited gorgeous red emission when exciting with UV or visible wavelengths. The synthesized particles show both hydrophilic and hydrophobic nature, depending on the stability of PEG and calcination temperature. The hydrophilic particles have the capacity to penetrate cells, translocate to the nucleus, and t...

Ca2Gd8(SiO4)6O2 (CGS) nanophosphors with different concentrations of single-doped Dy3+ ions and co-doped Dy3+/Eu3+ ions were prepared by a solvothermal synthesis. Very fine particles in the nanometer range could be achieved by this method, as evidenced by transmission electron microscope measurements. The hexagonal phase of the oxyapatite structure was confirmed by X-ray diffraction patterns. The energy transfer between Eu3+ and Dy3+ ions was investigated by photoluminescence excitation and emission properties. These phosphors had absorption bands in the UV and NUV region, which are suitable for the emission wavelength of UV or NUV light-emitting diodes (LEDs). With increasing the Eu3+ ion concentration, the emission peak intensity corresponding to the 5D0→7F2 transition increased and the yellow (4F9/2→6H13/2) emission intensity also increased compared to the blue (4F9/2→6H15/2) emission intensity due to the increased energy transfer between Dy3+ to Eu3+ ions. Thus, the Eu3+ ions compensated the red emission component of the Dy3+ doped CGS nanophosphors. Such phosphors are expected to have potential applications for NUV based white LEDs.

We reported the novel red-emitting phosphors of trivalent europium (Eu3+) ions activated CaGd4O7 (CG) prepared by a sol–gel method. After the samples were annealed at 1500 °C, the X-ray diffraction patterns confirmed their monoclinic structure and the transmission electron microscopy image showed the nanocrystallinity of the CG: Eu3+ phosphor. The photoluminescence excitation spectra exhibited the efficient energy transfer from the Gd3+ to Eu3+ by overlapping the f–f transition of Gd3+ excitation band with charge transfer band of Eu3+ ions. The photoluminescence (PL) spectra showed the emission band in the entire visible region at lower Eu3+ concentration and the red emission at higher Eu3+ concentration. All the decay curves were well fitted by single exponential functions. The temperature dependent luminescence measurements were performed for identifying the thermal stability of CG: Eu3+ phosphors at elevated temperatures. The cathodoluminescent (CL) spectra also presented a similar behavior to that observed in PL spectra. Form the PL, CL, and decay analysis the optimum concentration of Eu3+ ions in the CG host lattice was found to be 5 mol%. The CIE chromaticity coordinates varied from yellow to red in visible spectral region by increasing the Eu3+ concentration.