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1.
J Environ Radioact ; 275: 107426, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522413

RESUMO

Echinacea purpurea marc (EPM), a residual of echinacea herb after the extraction process, was used as a natural low-cost sorbent for competitive sorption of 152+154Eu(III), 60Co(II) and 134Cs(I) radionuclides. The EPM was ground to prepare it for use in the sorption process. The variables influencing the sorption process were assessed, including pH, contact time, concentrations of metal ions, and temperature. EPM was characterized by different analytical instruments such as FTIR, SEM, XRD, and DTA/TGA. pH 4.0 was selected as the ideal pH value for competitive sorption of the studied ions. Adsorption kinetics data found that the sorption followed a pseudo-second-order model. The adsorption isotherm data was significantly better suited by the Langmuir isotherms in the case of Eu(III) ions while following Freundlich in the case of Co(II) and Cs(I) ions. Positive ΔHo values confirm the endothermic character of metal ion sorption onto EPM. The loading efficiencies of Eu(III), Co(II), and Cs(I) ions in the EPM column were 66.67%, 9.59%, and 4.81%, respectively. The EPM is a cost-effective and efficient separation of Eu(III) ions more than Cs(I) and Co(II) ions. Therefore, in the future, it will be a starting point for the separation of trivalent elements of lanthanide ions.


Assuntos
Radioisótopos de Césio , Radioisótopos de Cobalto , Adsorção , Radioisótopos de Césio/química , Radioisótopos de Césio/análise , Radioisótopos de Cobalto/química , Európio/química , Cinética , Poluentes Radioativos do Solo/análise
2.
Appl Radiat Isot ; 191: 110558, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36410075

RESUMO

In this study, gamma rays were used as an initiator to prepare starch-acrylic acid/nanohalloysite, P(Stc-AA/NHal) composite for the removal of Co(II) from aqueous solutions. The characteristic peaks of P(Stc-AA/NHal) composite was confirmed by Fourier transform infrared spectroscopic analysis (FTIR). The morphological structure was examined using a scanning electron microscope (SEM). Differential thermal analysis (DTA) and thermogravimetric analysis (TGA) were also used to characterize the composite and demonstrate its high thermal stability. Using a batch sorption technique and 60Co as a radiotracer, the P(Stc-AA/NHal) composite was evaluated for Co(II) ions removal from aqueous solutions. The effect of pH, contact time, metal ion concentration, and temperature on Co(II) ions sorption were studied. The kinetic data of adsorption fit accurately with the pseudo-second-order adsorption model. Finally, the equilibrium adsorption results fitted the Langmuir isotherm model very well. The highest adsorption capacity measured was 103.6 mg g-1.


Assuntos
Acrilatos , Amido , Íons , Adsorção
3.
Int J Biol Macromol ; 229: 344-353, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36586656

RESUMO

A sustainable and efficient nanobentonite@sodium alginate@oleylamine (Nbent@Alg@OA) nanocomposite has been successfully synthesized via coating reaction of nanobentonite (Nbent) with alginate (Alg) and oleylamine (OA). The nanocomposite has been characterized and examined for the adsorption of 60Co(II) and 152+154Eu(III) radionuclides from simulated radioactive waste solution. FT-IR, XRD, SEM, and HR-TEM techniques have been applied to confirm the structural and morphological characteristics of the Nbent@Alg@OA nanocomposite. The effects of various parameters, such as pH of the medium, initial concentration of the radionuclides, contact time, and temperature on the adsorption of 60Co(II) and 152+154Eu(III) radionuclides were investigated by the batch adsorption technique. The results revealed that the optimum pH values for the adsorption of 152+154Eu (III) and 60Co (II) radionuclides were 4 and 5, respectively. The adsorption capacity of 152+154Eu(III) (65.6219 mg/g) was found greater than that of 60Co(II) (47.3469 mg/g). The adsorption process was found to be well described by the pseudo-second-order kinetic model. Furthermore, the equilibrium isotherm evaluation revealed that the Langmuir model was adequately matched with the adsorption data. According to the thermodynamic characteristics, the adsorption process was endothermic and spontaneous. Regeneration and reuse of Nbent@Alg@OA nanocomposite confirmed that the recycled nanocomposite was sufficiently efficient in several successive practical applications.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Alginatos/química , Radioisótopos de Cobalto , Nanocompostos/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética
4.
Appl Radiat Isot ; 178: 109970, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34619628

RESUMO

Khellin was successfully extracted from Ammi visnaga fruits with a recovery percent of 96.15%. Next radio-iodination of Khellin was successfully achieved with a high yield. The biodistribution study of [131I]iodo-khellin in tumour bearing mice revealed that khellin preferentially localization at tumour tissue. Target prediction study for [131I]iodo-khellin revealed that PI3K and VEGFR are potential targets for iodo-khellin with good affinity. The results of this study potentiate [131I]iodo-khellin as a good theranostic agent for tumour imaging and therapy.


Assuntos
Radioisótopos do Iodo/administração & dosagem , Quelina/metabolismo , Neoplasias/terapia , Medicina de Precisão , Animais , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Radioisótopos do Iodo/química , Quelina/química , Quelina/isolamento & purificação , Masculino , Camundongos , Simulação de Acoplamento Molecular , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Distribuição Tecidual
5.
Int J Biol Macromol ; 163: 79-86, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32603728

RESUMO

A simple and efficient separation method of carrier-free 47Sc from neutron irradiated titanium target using a novel chitosan-acrylic acid/multiwalled carbon nanotubes (CS-AA/MWCNTs) composite was established. The synthesis of the CS-AA/MWCNTs composite was achieved using gamma radiation-induced template polymerization. The grafting efficiency (GE%) of AA on CS onto the surface of f-MWCNTs reached a maximum of~84% under the optimized conditions (30 wt% CS, 1.0 wt% AA, 0.15 wt% f-MWCNTs, >0.2 wt% N,N'-Methylenebisacrylamide (NMBA), and irradiation dose ~25 kGy). Different analyses (FT-IR, SEM, TGA and DTA) were examined for confirming the structural morphology and mechanical properties of the new synthesized composite. Interestingly, the CS-AA/MWCNTs composite depicted a selective adsorption of Sc(III) rather than Ti(IV) ions at pH 5 with adsorption efficiency of ~93.93%. The ionic exchange separation of no-carrier-added (NCA)47Sc(III) from irradiated TiO2 target on CS-AA/MWCNTs composite packed column efficiently eluted 47Sc(III) by 91 ± 0.8% using 1 M HCl solution. The quality control tests (radionuclidic, radiochemical, and chemical purities) for the eluted 47Sc(III) clarified its high purity and validity for cancer theranostics.


Assuntos
Acrilatos/química , Quitosana/química , Resinas Compostas/síntese química , Nanotubos de Carbono/química , Nêutrons , Radioisótopos/isolamento & purificação , Escândio/isolamento & purificação , Titânio/química , Adsorção , Cromatografia Líquida , Resinas Compostas/química , Análise Diferencial Térmica , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Nanotubos de Carbono/ultraestrutura , Polimerização , Medicina de Precisão , Radioisótopos/análise , Radioisótopos/química , Escândio/análise , Escândio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Termogravimetria , Titânio/efeitos da radiação
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