RESUMO
A new biosorbent was fabricated by modification of bacterial cellulose biopolymer grafted with lanthanum sulfide decorated carboxylated multiwall carbon nanotube (La2S3@MWCNT@BC). The sorbent was employed in a green alternative dispersive-solid phase extraction of a variety of 14 pesticides in environmental water samples. The analyses were performed using GC-µECD. The properties and structure of La2S3@MWCNT@BC nanocomposite were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and adsorption-desorption isotherms. The composition of the sorbent was also investigated to evaluate the adsorptive properties of its constituents. The impact of various parameters influencing extraction efficacies such as sorbent dose, adsorption time, sample pH, ionic strength, and desorption conditions was investigated. The method was validated by specificity, matrix effect % (-0.4 to -7.4), enrichment factor (4-10), limits of quantification (0.007-0.31 µg L-1), matrix-matched calibration linearity (0.01-200 µg L-1), determination coefficients (r2=0.9921-0.9998), and precision. The optimized method was applied for the analysis of multiclass pesticides in seven environmental and drinking waters and the recoveries were obtained in the 81-108 % range with RSDs of 2.5-4.7 %. This paper is the first report on the synthesis and use of La2S3@MWCNT@BC nanocomposite to extract pesticides from different water samples. The greenness of the procedure was evaluated by the AGREE protocols.
Assuntos
Celulose , Lantânio , Nanotubos de Carbono , Praguicidas , Poluentes Químicos da Água , Nanotubos de Carbono/química , Lantânio/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Celulose/química , Praguicidas/análise , Praguicidas/química , Praguicidas/isolamento & purificação , Sulfetos/química , Limite de Detecção , Extração em Fase Sólida/métodosRESUMO
The pentavalent arsenic compound roxarsone (RSN) is used as a feed additive in poultry for rapid growth, eventually ending up in poultry litter. Poultry litter contains chicken manure, which plays a vital role as an affordable fertilizer by providing rich nutrients to agricultural land. Consequently, the extensive use of poultry droppings serves as a conduit for the spread of toxic forms of arsenic in the soil and surface water. RSN can be easily oxidized to release highly carcinogenic As(III) and As(IV) species. Thus, investigations were conducted for the sensitive detection of RSN electrochemically by developing a sensor material based on lanthanum manganese oxide (LMO) and functionalized carbon nanofibers (f-CNFs). The successfully synthesised LMO/f-CNF composite was confirmed by chemical, compositional, and morphological studies. The electrochemical activity of the prepared composite material was examined using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The obtained results confirmed that LMO/f-CNF showed enhanced electrocatalytic activity and improved current response with a good linear range (0.01-0.78 µM and 2.08-497 µM, respectively), exhibiting a low limit of detection (LOD) of 0.004 µM with a high sensitivity of 13.24 µA µM-1 cm-2 towards the detection of RSN. The noteworthy features of LMO/f-CNF composite with its superior electrochemical performance enabled reliable reproducibility, exceptional stability and reliable practical application in the analysis of tap water and food sample, affording a recovery range of 86.1-98.87%.
Assuntos
Compostos de Cálcio , Técnicas Eletroquímicas , Lantânio , Nanofibras , Óxidos , Roxarsona , Titânio , Nanofibras/química , Lantânio/química , Óxidos/química , Técnicas Eletroquímicas/métodos , Roxarsona/química , Roxarsona/análise , Titânio/química , Compostos de Cálcio/química , Poluentes Químicos da Água/análise , Carbono/química , Limite de Detecção , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Animais , Compostos de Manganês/químicaRESUMO
The rare earth metal element lanthanum (La) possesses carcinogenic, genotoxic, and accumulative properties, necessitating urgent development of an efficient and cost-effective method to remove La. However, current sorbents still encounter challenges such as poor selectivity, low sorption capacity, and high production costs. This study therefore proposes a promising solution: the creation of phytic acid-assisted sludge hydrochars (P-SHCs) to eliminate La from water and soil environments. This method harnesses phytic acid's exceptional binding ability and the economical hydrothermal carbonization process. P-SHCs exhibit robust sorption affinity, fast sorption kinetics, and excellent sorption selectivity for La when compared with pristine hydrochars (SHCs). This advantage arises from the remarkable binding ability of phosphate functional groups (polyphosphates) on P-SHCs, forming P-O-La complexes. Moreover, P-SHCs demonstrate sustained sorption efficiency across at least five cycles, with a slight decrease attributed to the loss of phosphorus species and mass during recycling. Furthermore, P-SHCs demonstrated superior economic feasibility, with a higher estimated cost-benefit ratio than that of other sorbents. Our study further validates the exceptional passivation capability of P-SHCs, showcasing relative stabilization efficiency ranging from 37.6 % to 79.6 % for La contamination. Additionally, acting as soil passivation agents, P-SHCs foster the enrichment of specific soil microorganisms such as Actinobacteria and Proteobacteria, capable of solubilizing phosphorus and resisting heavy metals. These findings present novel ideas and technical support for employing P-SHCs in combatting environmental pollution stemming from rare earth metals.
Assuntos
Lantânio , Ácido Fítico , Lantânio/química , Fósforo , Solo , Polifosfatos , AdsorçãoRESUMO
Attapulgite co-modified by lanthanum-iron (MT-LHMT) was used to study its effectiveness and mechanism in controlling phosphorus release from sediments. MT-LHMT has high adsorption capacity for phosphate and the maximum adsorption capacity of MT-LHMT to phosphate can reach 75.79 mg/g. The mechanism mainly involved electrostatic action, surface precipitation and ligand exchange between MT-LHMT bonded hydroxyl and phosphate to form La-O-P and Fe-O-P inner-sphere complexes. MT-LHMT has excellent adsorption performance in the pH range of 3-8. In addition to HCO3-, CO32- and HA- had a negative effect on the phosphorus removal of MT-LHMT, while NO3-, Cl-, SO42-, K+, Ca2+ and Mg2+ had a positive or no effect on phosphorus removal. MT-LHMT significantly reduced the risk of phosphorus release from overlying water in different dose effects and covering methods, as well as the unstable inactivation of flowing phosphorus, sediment dissolved reactive phosphorus (DRP) and available phosphorus with medium diffusion gradient in thin film in the sediment-water interface (Labile-PDGT). The MT-LHMT capping wrapped with fabric can reduce the risk of nitrogen release from sediment to overlying water more than only MT-LHMT capping. The results of this study showed that the MT-LHMT capping wrapped with fabric has high potential and can be used as an active capping material to manage the nitrogen and phosphorus load in surface water.
Assuntos
Fósforo , Poluentes Químicos da Água , Fósforo/química , Ferro/química , Lantânio/química , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Fosfatos , Nitrogênio , LagosRESUMO
A novel lanthanum-modified-chitosan-attapulgite (La-CTS-ATP) composite with efficient adsorption of phosphate in water was prepared and characterized. The adsorption properties were investigated by adsorption kinetics, adsorption isotherms and thermodynamics. An orthogonal design test was used to explore the optimal preparation conditions of La-CTS-ATP. Various characterizations exhibited the successful modification of lanthanum and the effective adsorption of phosphate. The batch experiments showed that La-CTS-ATP exhibited excellent stability within pH range of 4-10 and the disturbance of co-existing substances (Cl-, NO3-, HCO3-, SO42-). Chemisorption played the main role in phosphate adsorption from kinetic studies. Isotherm studies illustrated monolayer uptake of adsorbents onto the adsorbent, and the maximum adsorption capacity was 102.90 mg/g, much higher than other La-based adsorbents. The reaction process was spontaneous (ΔG < 0), exothermic (ΔH < 0) and disordered (ΔS > 0) from thermodynamic analysis. The excellent reusability of La-CTS-ATP was investigated, after five cycles, the phosphate removal rate and desorption rates were 72.93 % and 77.44 %, respectively. The dynamic adsorption experiments showed that the faster the flow rate, the shorter the time for La-CTS-ATP to get saturation, and the maximum adsorption capacity was slightly reduced. The surface precipitation, electrostatic attraction, and ligand exchange were the main mechanisms affecting its adsorption behavior. The adsorbent exhibited excellent effectiveness in real wastewater (breeding wastewater and domestic wastewater). In this study, a novel and effective adsorbent for phosphorus removal was produced in contaminated water, and the analysis of the adsorption process of the system provides new insights for related research.
Assuntos
Quitosana , Poluentes Químicos da Água , Fosfatos/química , Água/química , Lantânio/química , Quitosana/química , Cinética , Águas Residuárias , Adsorção , Poluentes Químicos da Água/química , Trifosfato de Adenosina , Concentração de Íons de HidrogênioRESUMO
In the present work, 5 wt% CaB6/hydroxyapatite (HA) bioceramic coatings with different La2O3contents (0-0.6 wt%) have been fabricated by a laser cladding technique on Ti-6Al-4V. The effects of La2O3contents on microstructure and properties of the laser-cladded 5 wt% CaB6/HA coatings have been carefully investigated. The results show that the microstructure is obviously refined, and the structure is relatively uniform after doping 0.2-0.4 wt% La2O3. As the La2O3content increases, the corrosion resistance are found to increase firstly and then gradually decrease. The x-rays diffraction analysis confirms that the amount of HA and TCP (calcium phosphate) in the coating reaches maximum after doping 0.2 wt% La2O3. The La2O3-doped coatings show a significantly higher bone-like apatite precipitation after immersion in simulated body fluid compared with La2O3-free coating. In vitro experiment also shows that 5 wt% CaB6/HA bioceramic coatings with 0.2-0.4 wt% La2O3are more suitable for the attachment and proliferation of MG63 cells, exhibiting superior bioactivity and biocompatibility.
Assuntos
Materiais Biocompatíveis , Cerâmica , Lantânio/química , Óxidos/química , Ligas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/toxicidade , Fosfatos de Cálcio/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cerâmica/química , Cerâmica/farmacologia , Cerâmica/toxicidade , Durapatita/química , Humanos , Lasers , Modelos Biológicos , Titânio/químicaRESUMO
In this work, extract from leaves of Couroupita guianensis (C.guianensis) abul was used as a potential reducing agent for the synthesis of lanthanum oxide (La2O3) nanoparticles (NPs). In addition, the morphology and several physicochemical properties of the La2O3 NPs were improved by introducing the ionic liquid of 1-butyl 3-methyl imidazolium tetra fluoroborate (BMIM BF4) as a stabilizing agent. The structure of the La2O3 (without ionic liquid) and IL-La2O3 (with ionic liquid) NPs were analyzed by X-ray diffraction (XRD). The chemical composition of the synthesized NPs was analyzed using the energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) studies. Optical and morphological studies were also performed. The antibacterial, antioxidant, anti-inflammatory, anti-diabetic and anticancer properties of the La2O3 and IL-La2O3 NPs were evaluated.
Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Química Verde , Hipoglicemiantes/farmacologia , Lantânio/farmacologia , Óxidos/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/metabolismo , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Lantânio/química , Lantânio/metabolismo , Lecythidaceae/química , Nanopartículas/química , Nanopartículas/metabolismo , Óxidos/química , Óxidos/metabolismo , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Propriedades de SuperfícieRESUMO
The superoxide radical ion is involved in numerous physiological processes, associated with both health and pathology. Its participation in cancer onset and progression is well documented. Lanthanum(III) and gallium(III) are cations that are known to possess anticancer properties. Their coordination complexes are being investigated by the scientific community in the search for novel oncological disease remedies. Their complexes with 5-aminoorotic acid suppress superoxide, derived enzymatically from xanthine/xanthine oxidase (X/XO). It seems that they, to differing extents, impact the enzyme, or the substrate, or both. The present study closely examines their chemical structure by way of modern methods-IR, Raman, and 1H NMR spectroscopy. Their superoxide-scavenging behavior in the presence of a non-enzymatic source (potassium superoxide) is compared to that in the presence of an enzymatic source (X/XO). Enzymatic activity of XO, defined in terms of the production of uric acid, seems to be impacted by both complexes and the pure ligand in a concentration-dependent manner. In order to better relate the compounds' chemical characteristics to XO inhibition, they were docked in silico to XO. A molecular docking assay provided further proof that 5-aminoorotic acid and its complexes with lanthanum(III) and gallium(III) very probably suppress superoxide production via XO inhibition.
Assuntos
Inibidores Enzimáticos/química , Gálio/química , Lantânio/química , Ácido Orótico/análogos & derivados , Superóxidos/química , Xantina Oxidase/antagonistas & inibidores , Ácido Orótico/químicaRESUMO
Lanthanide ions (Ln3+) doped hydroxyapatite (HAP) particles are well established in biomedical areas. Although Ln elements are closely located in the periodic table and have plenty of similar characteristics, the minor differences in the effective ionic radii could cause alterations in the physicochemical and biological properties of HAP substitutes. The present study synthesized lanthanum-(La-) and gadolinium-(Gd-) doped HAP particles (La-HAP and Gd-HAP). And the effects of two types of particles on bone marrow stem cells (BMSCs) viability were also measured and compared in vitro. The results indicated that the Gd-HAP adsorbed more serum proteins from culture media and inhibited the new layer of apatite formation on its surface when comparing to La-HAP with a similar crystalline structure, particle size, and Zeta potential. These surface modifications can significantly reduce the cell adhesion of Gd-HAP, simultaneously decreasing the Gd-HAP particle uptake efficiency. Moreover, the cell viability of Gd-HAP remained higher than that of La-HAP in culture periods. We concluded that a slight variation in the effective ionic radii between Gd3+ and La3+ could alter the adsorption of serum proteins on the particles' surface, modulating subsequent cellular responses. The present work provides an interesting view that Gd-HAP is endowed with better cellular biocompatibility than La-HAP.
Assuntos
Materiais Biocompatíveis/química , Durapatita/química , Gadolínio/química , Lantânio/química , Adsorção , Animais , Materiais Biocompatíveis/farmacologia , Proteínas Sanguíneas/química , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , RatosRESUMO
Rationale: Osteoporotic patients suffer symptoms of excessive osteoclastogenesis and impaired osteogenesis, resulting in a great challenge to treat osteoporosis-related bone defects. Based on the positive effect of rare earth elements on bone metabolism and bone regeneration, we try to prove the hypothesis that the La3+ dopants in lanthanum-substituted MgAl layered double hydroxide (La-LDH) nanohybrid scaffolds simultaneously activate osteogenesis and inhibit osteoclastogenesis. Methods: A freeze-drying technology was employed to construct La-LDH nanohybrid scaffolds. The in vitro osteogenic and anti-osteoclastogenic activities of La-LDH nanohybrid scaffolds were evaluated by using ovariectomized rat bone marrow stromal cells (rBMSCs-OVX) and bone marrow-derived macrophages (BMMs) as cell models. The in vivo bone regeneration ability of the scaffolds was investigated by using critical-size calvarial bone defect model of OVX rats. Results: La-LDH nanohybrid scaffolds exhibited three-dimensional macroporous structure, and La-LDH nanoplates arranged perpendicularly on chitosan organic matrix. The La3+ dopants in the scaffolds promote proliferation and osteogenic differentiation of rBMSCs-OVX by activating Wnt/ß-catenin pathway, leading to high expression of ALP, Runx-2, COL-1 and OCN genes. Moreover, La-LDH scaffolds significantly suppressed RANKL-induced osteoclastogenesis by inhibiting NF-κB signaling pathway. As compared with the scaffolds without La3+ dopants, La-LDH scaffolds provided more favourable microenvironment to induce new bone in-growth along macroporous channels. Conclusion: La-LDH nanohybrid scaffolds possessed the bi-directional regulation functions on osteogenesis and osteoclastogenesis for osteoporotic bone regeneration. The modification of La3+ dopants in bone scaffolds provides a novel strategy for osteoporosis-related bone defect healing.
Assuntos
Regeneração Óssea/efeitos dos fármacos , Lantânio/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Alicerces Teciduais/química , Animais , Regeneração Óssea/genética , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dioxigenases/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Lantânio/química , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , NF-kappa B/metabolismo , Nanoestruturas/ultraestrutura , Osteocalcina/metabolismo , Osteogênese/genética , Osteoporose/metabolismo , Ligante RANK/farmacologia , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genéticaRESUMO
OBJECTIVES: Although halophilic archaea are rich in natural environments, their biotechnological applications are not as prevalent as those of other extremophiles, such as thermophiles and alkaliphiles. This study presents an simple method to prepare a hydrogel composite using crude cell lysate of a halophilic archaea, Halorubrum ejinoor sp. (H.e.) which was isolated from a saline lake in Inner Mongolia, China. Furthermore, formation mechanism and potential applications of the hydrogel as an adsorbing material are discussed. RESULTS: Halorubrum ejinoor sp. (H.e.) cell lysate was firstly prepared by adding pure water onto the H.e. cell pellet, followed by a short incubation at 60 °C. The cell lysate was injected into different metal ion (or H+) solutions to obtain the hydrogel composite. It was observed that H+, Fe3+, La3+, Cu2+, and Ca2+ induced gelation of the cell lysate, while Fe2+, Co2+, Ni2+, Mg2+, Na+, and K+ did not. DNA and extracellular polysaccharides (EPS) in the H.e. cell lysate were found to be responsible for the gelation reaction. These results suggest that DNA and EPS should be crosslinked by metal ions (or H+) and form a networked structure in which the metal ion (or H+) serves as an anchor point. Potential application of the hydrogel as an adsorbing material was explored using La3+-induced H.e. hydrogel composite. The hydrogel composite can adsorb the fluoride, phosphate and DNA-binding carcinogenic agents, such as acridine orange. CONCLUSIONS: The simplicity and cost effectiveness of the preparation method might make H.e. hydrogel a promising adsorbing material. This work is expected to expand the technical applications of haloarchaea.
Assuntos
Extratos Celulares/química , Halorubrum/química , Hidrogéis/síntese química , Lantânio/química , Laranja de Acridina/análise , Adsorção , DNA Arqueal/química , Fluoretos/análise , Hidrogéis/química , Fosfatos/análise , Polissacarídeos/químicaRESUMO
In this study, we report on antiproliferative benzyloxy dihydropyrimidinones (DHPMs) produced by the Biginelli reaction of benzyloxy benzaldehyde, urea, and diverse 1,3-diones. The reaction was catalyzed by lanthanum triflate and completed within 1-1.5 h, with 74-97% yield. The antiproliferative assay was carried out for all synthesized dihydropyrimidinones against six human solid tumor cell lines. Six compounds showed good antiproliferative activity with GI50 values below 5 µM. Among all the synthesized compounds, the most potent derivative showed good antiproliferative activity against all cell lines with GI50 values in the range of 1.1-3.1 µM. These DHPMs comply with druglikeness. Furthermore, ADMET prediction and the effect of P-glycoprotein on the antiproliferative activity were also studied. Overall, our method allows eco-friendly access to benzyloxy DHPMs as potential anticancer drugs.
Assuntos
Antineoplásicos , Proliferação de Células/efeitos dos fármacos , Pirimidinonas , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lantânio/química , Estrutura Molecular , Pirimidinonas/síntese química , Pirimidinonas/química , Pirimidinonas/farmacologia , Relação Estrutura-Atividade , Ureia/químicaRESUMO
Luminescent Ln3+ -doped nanoparticles (NPs) functionalised with the desired organic ligand molecules for haemocompatibility studies were obtained in a one-pot synthesis. Chelated aromatic organic ligands such as isophthalic acid, terephthalic acid, ibuprofen, aspirin, 1,2,4,5-benzenetetracarboxylic acid, 2,6-pyridine dicarboxylic acid and adenosine were applied for surface functionalisation. The modification of the nanoparticles is based on the donor-acceptor character of the ligand-nanoparticle system, which is an alternative to covalent functionalisation by peptide bonding as presented in our recent report. The aromatic groups of selected ligands absorb UV light and transfer their excited-state energy to the dopant Eu3+ ions in LaF3 and SrF2 NPs. Herein, we discuss the structural and spectroscopic characterisation of the NPs and the results of haemocompatibility studies. Flow cytometry analysis of the nanoparticles' membrane-binding is also presented.
Assuntos
Eritrócitos/efeitos dos fármacos , Európio/farmacologia , Fluoretos/farmacologia , Lantânio/farmacologia , Nanopartículas/química , Estrôncio/farmacologia , Relação Dose-Resposta a Droga , Európio/química , Fluoretos/química , Humanos , Lantânio/química , Ligantes , Estrutura Molecular , Estrôncio/química , Relação Estrutura-AtividadeRESUMO
Photodynamic therapy (PDT) applications are limited by the low penetration of UV-visible light into biological tissues. Considering X-rays as an alternative to excite photosensitizers (PS) in a deeper tumor, an intermediate particle able to convert the X-ray energy into visible light (scintillating nanoparticle, ScNP) is necessary. Moreover, accumulation of PS in the target cells is also required. Genetically encoded proteins could be used as a photosensitizer, allowing the exclusive expression of PS inside the tumor cells. Here, the interaction of eGFP, KillerOrange, and KillerRed proteins with LaF3:Tb3+ ScNP was investigated, for the first time, in terms of its physicochemical and energy transfer properties. The protein structure, stability, and function were evaluated upon adverse physiological conditions and X-ray irradiation. Optimal parameters for energy transfer from ScNP to the proteins were investigated, paving the way for the use of genetically encoded photosensitizers for applications in X-ray activated photodynamic therapy.
Assuntos
Fluoretos/química , Lantânio/química , Proteínas Luminescentes/química , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Térbio/química , Linhagem Celular Tumoral , Transferência de Energia , Humanos , Proteínas Luminescentes/genética , Modelos Moleculares , Nanopartículas/ultraestrutura , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/metabolismo , Raios XRESUMO
Generally, the addition of exogenous stem cells and host-to-scaffold immune responses restricts the clinical applications of hydroxyapatite (HA)/chitosan (CS) scaffolds for bone regeneration. To achieve "facilitated endogenous tissue engineering", magnetic M-type hexagonal ferrite (SrFe12O19) nanoparticles were incorporated into bone scaffolds to recruit endogenous stem cells. Then, lanthanum incorporation was utilized to regulate host-to-scaffold immune responses and to provide a pro-regenerative environment for recruited endogenous stem cells. Here, we first fabricated and characterized magnetic lanthanum-doped HA/CS scaffolds. The MLaHA/CS scaffolds were demonstrated to be effective at recruiting rat bone marrow mesenchymal stem cells (rBMSCs) and modulating host-to-scaffold immune responses by promoting macrophage polarization into the anti-inflammatory phenotype (M2) in vitro. By further examining the underlying mechanism, we found that MLaHA/CS scaffolds could promote the osteogenic differentiation of rBMSCs by upregulating the phosphorylation of the Smad 1/5/9 pathway. When MLaHA/CS scaffolds were implanted into rat calvarial defects, the incorporation of magnetic nanoparticles and lanthanum significantly promoted the new bone regeneration, as revealed by micro-CT assays and histological staining. Our findings suggest that MLaHA/CS shows great potential for use as a cell-free and biocompatible scaffold for bone regeneration.
Assuntos
Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Quitosana/farmacologia , Durapatita/farmacologia , Imunomodulação/efeitos dos fármacos , Lantânio/farmacologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Regeneração Óssea/imunologia , Quitosana/química , Durapatita/química , Lantânio/química , Fenômenos Magnéticos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Camundongos , Tamanho da Partícula , Células RAW 264.7 , Propriedades de SuperfícieRESUMO
The present work demonstrated the invention of synergistically strengthen of chemical and biological removal of phosphorus (P) in biological wastewater treatment, which was achieved by exposure the bioreactors to different levels of La-based-adsorbents. We fabricated a high-performance La2O2CO3 micro-adsorbent (H-La2O2CO3) and added it into sequencing batch reactors. When activated sludge was exposed to 40 mg/L H-La2O2CO3 for 40 d, effluent total phosphorus (TP) concentration significantly decreased to approximately 0.18 mg/L, with the steady removal efficiency of 96.4%, which is superior to the biological phosphorus removal (BPR). The effect of H-La2O2CO3 dosages on P removal in biological wastewater treatment was also detailedly investigated. The H-La2O2CO3 adsorbent could not only capture P by chemical bonding itself, but also increased protein (PN) contents of extracellular polymeric substances (EPS) and changed the functional group of EPS to chemically adsorb P. Additionally, the results of 16s rDNA molecular analysis revealed that the species richness and microbial diversity varied with the different dosages of adsorbent. Sequence analyses showed that the appropriate concentration of H-La2O2CO3 addition increased the contents of several polyphosphate accumulating organisms (PAOs) at genus level in sludge.
Assuntos
Reatores Biológicos/microbiologia , Carbonatos/química , Lantânio/química , Fósforo/análise , Esgotos/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Microbiota/efeitos dos fármacos , Polifosfatos/análise , RNA Ribossômico 16S , Esgotos/microbiologia , Águas Residuárias/microbiologiaRESUMO
In the present work, talc (a low-cost clay) encapsulated salts alginate (TAL) beads were synthesized by cross-linking with lanthanum ion and tested for phosphate adsorption. Multiple methods were applied for the characterization of composites. The combined effect of talc and lanthanum improved phosphate removal performance of TAL beads. Factors such as talc content, La3+ concentration, adsorbent dosage, pH, co-existing ions (Cl-, NO3- and SO42-) were studied in batch experiments. The optimized TAL-7 beads exhibited satisfactory selectivity towards phosphate in the coexistence of competing anions and could remain efficient phosphate removal in the pH range of 4-6. The phosphate removal efficiency reached to 95% with a maximum uptake of 16.4 mg P/g obtained at the optimal pH 4. Further experiments suggested that Langmuir isotherm model and the pseudo-second-order kinetic model could well describe the phosphate adsorption process of TAL-7 beads. Moreover, TAL-7 beads exhibited superior phosphate fixation performance in the long-term experiment. The results from adsorption experiment and characterization analysis demonstrated that TAL-7 beads could be a cost-effective and promising biosorbent for phosphate adsorption and fixation in the aqueous environment.
Assuntos
Alginatos/química , Hidrogéis/química , Lantânio/química , Fosfatos/análise , Talco/química , Poluentes Químicos da Água/análise , Adsorção , Ânions , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Fosfatos/química , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodosRESUMO
Osteogenic differentiation is great significance for improving the bone regeneration. Present study evaluates the osteogenic ability of lanthanum (La3+) and silicate (SiO44-) substituted hydroxyapatite (MHAP) - polymeric composite coated surface treated titanium (Ti) implant. The bio-ceramic MHAP was synthesized by hydrothermal process with assistance of calcium alginate template. For enhance the hydrophilicity, the polymer poly (vinyl pyrrolidone) (PVP) was included in the composite by ultra-sonication method. The negative zeta potential value -9.97 mV of Ca-alg/ La, Si-HAP was observed after the incorporation of PVP in the matrix. Incorporation of minerals and PVP polymer was confirmed and analyzed by Energy Dispersive X-ray analysis (EDX), Fourier Transform Infra-Red spectroscopy (FT-IR) and Electron Microscopy techniques. A compact coating of the composite with the thickness of 448 nm on Ti surface was achieved by Electrophoretic deposition (EPD) method. The in-vitro MTT assay method and alkaline phosphate ALP activity (94% and 0.94 a.u respectively for the optimized composite) were utilized to determine the cell viability and differentiation on human Bone Marrow-Derived Stem Cells (hBMSCs). The osteogenic ability of bio-composite coated Ti in hBMSCs and in-vivo rat model has strongly suggests the fabricated Ti plate with bio-composite coatings can act as promising biomaterial for orthopedics.
Assuntos
Alginatos/farmacologia , Prótese Ancorada no Osso , Interface Osso-Implante/cirurgia , Materiais Revestidos Biocompatíveis , Hidroxiapatitas/farmacologia , Osseointegração/efeitos dos fármacos , Tíbia/cirurgia , Titânio/química , Alginatos/química , Fosfatase Alcalina/metabolismo , Animais , Interface Osso-Implante/fisiopatologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Composição de Medicamentos , Humanos , Hidrogéis , Hidroxiapatitas/química , Lantânio/química , Lantânio/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Desenho de Prótese , Ratos Wistar , Recuperação de Função Fisiológica , Silicatos/química , Silicatos/farmacologia , Propriedades de Superfície , Tíbia/fisiopatologiaRESUMO
Prostate cancer is one of the primary causes of death around the world. As an important drug, flutamide has been used in the clinical diagnosis of prostate cancer. However, the over dosage and improper discharge of flutamide could affect the living organism. Thus, it necessary to develop the sensor for detection of flutamide with highly sensitivity. In this paper, we report the synthesis of lanthanum cobaltite decorated halloysite nanotube (LCO/HNT) nanocomposite prepared by a facile method and evaluated for selective reduction of flutamide. The as-prepared LCO/HNT nanocomposite shows the best catalytic performance towards detection of flutamide, when compared to other bare and modified electrodes. The good electrochemical performance of the LCO/HNT nanocomposite modified electrode is ascribed to abundant active sites, large specific surface area and their synergetic effects. Furthermore, the LCO/HNT modified electrode exhibits low detection limit (0.002 µM), wide working range (0.009-145 µM) and excellent selectivity with remarkable stability. Meaningfully, the developed electrochemical sensor was applied in real environmental samples with an acceptable recovery range.
Assuntos
Poluentes Ambientais/análise , Flutamida/análise , Lantânio/química , Nanocompostos/química , Catálise , Argila , Técnicas Eletroquímicas/métodos , Eletrodos , Grafite/química , Humanos , Limite de Detecção , Minerais , Nanotubos/químicaRESUMO
We report the first targeted nuclear medicine application of the lanthanum radionuclides 132/135 La. These isotopes represent a matched pair for diagnosis via the positron emissions of 132 La and therapy mediated by the Auger electron emissions of 135 La. We identify two effective chelators, known as DO3Apic and macropa, for these radionuclides. The 18-membered macrocycle, macropa, bound 132/135 La with better molar activity than DO3Apic under similar conditions. These chelators were conjugated to the prostate-specific membrane antigen (PSMA)-targeting agent DUPA to assess the use of radiolanthanum for in vivo imaging. The 132/135 La-labeled targeted constructs showed high uptake in tumor xenografts expressing PSMA. This study validates the use of these radioactive lanthanum isotopes for imaging applications and motivates future work to assess the therapeutic effects of the Auger electron emissions of 135 La.