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Rare earth elements (REEs) have been found broad applications in superconductive materials, catalysts, magnetics, hydrogen storage materials, and rechargeable batteries. By integrating REEs into different fields, their waste has caused severe environmental and health problems due to their contamination with groundwater sources and soil. Therefore, separating and recycling these elements from water sources and soil has become an urgent issue. The traditional methods for sequestration of the REEs from aqueous solutions are ion exchange, precipitation, solvent extraction, and adsorption. Adsorption is a promising technology for recovering REEs due to its facile application, economical, non-toxicity, and reusability. There are many adsorbent materials, such as carbon-based nanostructures, cyclodextrin, silica-based materials, organic and inorganic-based polymers etc., utilized for this approach. In recent years, researchers have focused on developing new hydrogel materials with highly porous morphology and cross-linked three-dimensional polymer networks, proven to be excellent sorbents for metal ions. However, their application for removing the REEs is very limited. In this study, we developed and characterized a shungite-based poly(vinyl alcohol) (PVA) hybrid hydrogel as a potential sorbent material for removing REEs. As an inorganic filler, shungite, a natural carbon-based mineral, has been integrated into the PVA-based hydrogel. The shungite-PVA hydrogel was synthesized using a freezing-thawing method using boric acid as a crosslinking agent. The surface morphology was investigated by scanning electron microscope (SEM) (Fig.1), and SEM images revealed homogenous pores on the surface of pure PVA hydrogel. After introducing shungite as an inorganic filler, most pores filled with shungite. In this study, the synthesized shungite-PVA hydrogels were used to sequestrate lanthanum (La3+) ions from aqueous solutions. The shungite-PVA hydrogels exhibited a high affinity towards La3+ ions with 39.1 mg/g uptake ratio for the contact time, and 51.4 mg/g maximum capacity. To investigate the kinetics of La3+ ion adsorption onto Shungite- PVA hydrogels, the non-linear forms of conventional kinetic models were used, namely pseudofirst and pseudo-second order rate laws. The plotted data was well-fitted to pseudo-second order with R2=0.999. Furthermore, the adsorption capacity and affinity of shungite-PVA hydrogel towards La3+ were evaluated by adsorption isotherms viz. Langmuir and Freundlich. Based on R2 values, the Langmuir model fits better with the experimental data and showed the adsorption of La3+ is deemed as monolayer adsorption. No sponsor

The contamination of water with dyes is a critical problem for the environment and a great deal of research is invested to produce the novel adsorbent composites with high adsorption capacity and at the same time gaining a major goal to alleviate their non-biodegradable and toxic nature. Therefore, many researchers put their attention to developing sustainable, biodegradable and nontoxic adsorbent systems with the photocatalytic property. Herein, a nanocarbon based natural source called shungite (SHT)was combined with PVA hydrogel to illustrate the degradation of aluminescent Bodipy dye in an aqueous solution via UV-light irradiation. SHT-PVA hydrogels have been characterized by FTIR and studied their swelling properties and thermal behaviors by TGA. No sponsor

In this study, PEG-L-ASNase enzyme was immobilized on UCNPs and its activity was improved by NIR. NaYF4: Yb3+, Er3+/PEI UCNPs were characterized to observe structural and morphological changes before/after enzyme immobilization. Additionally, optimum pH and optimum temperature values were determined for PEG-L-ASNase and NaYF4: Yb3+, Er3+/PEI-PEG-L-ASNase. While the optimum pH value was found to be 8.5 and 8 for PEG-L-ASNase and NaYF4: Yb3+, Er3+/PEI-PEG-L-ASNase, the optimum temperature values were determined as 40 oC and 45 oC, respectively. Also, after incubation at 50 °C for 6 hours, it was observed that PEG-L-ASNase and NaYF4: Yb3+, Er3+/ PEI-PEG-L-ASNase retained 28% and 59% of their initial activities, respectively. Moreover, the kinetic parameters (Km and Vmax) were calculated. These values for PEG-L-ASNase were found as 2.31 ± 0.04 mM and 140.85 ± 3.23 μmol/min, respectively. For NaYF4: Yb3+, Er3+/PEI-PEG-L-ASNase, the Km and Vmax values were calculated as 1.56 ± 0.06 mM and 138.89 ± 1.66 μmol/min, respectively. Finally, it was determined that the application of NIR at 800 mW, for 60 min at 1 cm increased the activity approximately 4 times compared to the PEG-L-ASNase. As a result, L-ASNase was successfully immobilized and the activity of the immobilized enzyme was increased approximately 4 times by using NIR light. Also, in this study is one of the pioneering studies in terms of the development of triggerable drug delivery systems. No sponsor

Theranostics is new term which defined as a combination of therapy and diagnosis to establish a targeted drug delivery and monitoring of treatment into a single nanosystem. The most important parameter in the theranostic platforms is their stability to be able to increase the crossing some biological barriers and avoid the aggregation in the circulatory system. Therefore, polymeric nanoparticles are highly desirable to design novel nanotheranostics due to their improved pharmacokinetic properties, stability in physiological conditions, biocompatibility, and biodegradability. In our studies, we designed and synthesized some polymeric nanocapsules and one part of these nanocapsules utilized as a pH responsive nanosystem which includes Doxorubicin (Dox), a chemotherapeutic drug, and upconversion nanoparticles (UCNPs) as a luminescent probe and the other part of the nanocapsules were used for the photodynamic therapy (PDT) by loading the capsules with photosensitizer molecules, a derivative of Bodipy. Both studies exhibited excellent stability in phosphate buffered solutions (pH:7.4) which is proved by Zetasizer measurements, dynamic light scattering studies and stability tests. The size of the nanocapsules were dramatically decreased by increasing the stirring rate. In the first study, the nanocapsules were loaded with Dox up to ~63 % efficiency and acid-induced release (~47 %) obtained at pH 3.6 and 5.5. It was found that encapsulation decreased toxicity of UCNPs as confirmed in a cellular assay (L-929 and MCF-7 cell lines). In the second study, a higher encapsulation efficiency of Bodipy has been observed. The singlet oxygen measurements of the Bodipy encapsulated nanocapsules have been done in the presence of a trap molecule, resulted in a promising PDT activity. As a result, for both studies, a less soluble drug molecules in solution become highly soluble via encapsulation technology using a polysaccharide nanocapsule. Further studies, such as biological experiments are ongoing. No sponsor

Photodynamic therapy (PDT) is an alternative clinically approved treatment method to obliterate the cancerous lesion by producing reactive oxygen species (ROS) via activated photosensitizer (PS) molecule at a certain wavelength1. In recent years, Bodipy (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) as a photosensitizer molecule has been extensively investigated in PDT2,3. However, the use of many Bodipy PS in PDT has been limited due to their insolubility in aqueous solutions. Therefore, nanotechnology offers tremendous solutions to building up nano-carrier systems for insoluble molecules. We have herein developed a stable formulation of hybrid Bodipy PS via conjugation of TiO2 nanoparticles to the Bodipy PS. In this study, a heavy metal substituted Bodipy PS molecule has been synthesized and linked to polyethyleneimine (PEI) functionalized TiO2 nanoparticles to increase the stability and biocompatibility of the photosensitizer in physiological conditions (pH:7.4) as a potential photodynamic therapy agent and investigated PDT effect on CRL-4010 and MDA-MB-231 cancer cells. No sponsor

In the present study, polyethyleneimine (PEI) coated superparamagnetic iron oxide nanoparticles (SPIONs) having the size of 15 nm in diameter with high magnetic saturation (60 emu/g) have been prepared by co-precipitation method. The synthesized PEI-Fe3O4 nanoparticles have been fully characterized by transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) techniques. The free amine groups on the PEI-Fe3O4 surface has been covalently functionalized with carboxymethyl cellulose (CMC) by the catalysis of N,N'-Dicyclohexylcarbodiimide (DCC) and N, N'-Dimethylpyridin-4-amine (DMAP) coupling to produce CMC-Fe3O4 nanocarriers. The prepared CMC-Fe3O4 nanocarriers have been loaded with a well-known anti-tumor drug doxorubicin (Dox) and investigated its loading and releasing profiles from the nanocarrier. The CMC acted as an excellent nanocarrier for Dox with a loading efficiency ≈ 86%. The drug releasing profile has been studied at different pH values (3.5; 5.5; and 7.4). When the pH of the release medium (phosphate buffer solution) was changed from 7.4 to 5.5 or 3.6, the drug release has been increased which indicates that the drug releasing is pH dependent. No sponsor

Proceeding In this study, carboxymethyl cellulose (CMC) functionalized superparamagnetic iron oxide nanoparticles (SPIONs) have been synthesized as a novel theranostic platform which enables magnetic resonance (MR) imaging-guided and pH-responsive targeted drug delivery. In order to build up this platform, firstly, polyethyleneimine (PEI) modified SPIONs with the size of 15 nm in diameter have been preapared by coprecipitation technique. Then, the free amine groups on the PEI-SPIONs surface has been further functionalized covalently with CMC by the catalysis of N,N'-dicyclohexylcarbodiimide (DCC) and N,N'-dimethylpyridin-4-amine (DMAP) coupling to produce CMC-SPIONs. After the surface modification of PEI-SPIONs with CMC, the saturation magnetization just decreased from 60 to 58 emu/g compared to PEI-SPIONs which indicated that the CMC-SPIONs could be used as T1 agent in MRI. The resultant CMC-SPIONs have been loaded with a well-known anti-tumor durg Doxorubicin (Dox) and investigated its loading and releasing profiles from the nanocarrier. The CMC acted as an excellent nanocarrier for Dox with a loading efficinecy ≈ 86%. The drug releasing profile has been studied at different pH values (3.5; 5.5; and 7.4). The results show that when the pH of the release medium (phosphate buffer solution) was changed from 7.4 to 5.5 or 3.6, the Dox release has been incereased which indicates that the Dox releasing is pH dependent for the developed platform. The study provides a method to fabricate a multifunctional magnetic nanocarrier platform without loosing its magnetic efficiency during functionalization process and may utilize for biomedical imaging and cancer therapy. No sponsor

TiO2 nanoparticles conjugated luminescence upconversion (TiO2-UC) nanocomposites have been fabricated by covalently linking of carboxyl-functionalized TiO2 and amino-functionalized NaYF4:Yb3+,Er3+,Ce3+ upconversion nanoparticles (UCNP) in the presence of N,N'–dicyclohexylcarbodiimide (DCC) /4-dimethylaminopyridine (DMAP) coupling reagents. The carboxyl-functionalized TiO2 nanoparticles and amino-functionalized UCNPs have been synthesized by hydrothermal method with 5±2 and 55±10 nm in diameter, respectively. In the synthesis of UCNPs, the percentage of stabilizing agent (polyethyleneimine, PEI), the mole ratios of NaCl/NH4F and the co-doping ratio of Ce3+ ion have been found to be a significant effect on their size and morphology. Size, morphology, conjugation as well as photo-physical properties of all synthesized nanomaterials have been characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and fluorescence spectroscopy. UCNPs and TiO2-UCnanocomposites exhibit strong green luminescence at room temperature under 980 nm excitation leaded the emissions at 440, 520, 540 and 658 nm, representing 2H9/2 → 4 I15/2, 2H11/2→4 I15/2, 4 S3/2→4 I15/2 and 4 F→4 I15/2 transitions, respectively. The water dispersible luminescence nanocomposites having NIR light utilizing ability are promising for efficient light harvesting and/or bio-imaging applications. No sponsor