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1.
Biol Trace Elem Res ; 202(5): 2391-2401, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37597070

RESUMO

Alendronate-functionalized graphene quantum dots (ALEN-GQDs) with a quantum yield of 57% were synthesized via a two-step route: preparation of graphene quantum dots (GQDs) by pyrolysis method using citric acid as the carbon source and post functionalization of GQDs via a hydrothermal method with alendronate sodium. After careful characterization of the obtained ALEN-GQDs, they were successfully employed as sensing materials with superior selectivity and sensitivity for the detection of nanomolar levels of arsenic ions (As(III)). According to the mechanistic investigation, arsenic ions can quench the fluorescence intensity of ALEN-GQDs through metal-ligand interaction between the As(III) ions and the surface functional groups of the fluorescent probe. This probe provided a rapid method to monitor As(III) with a wide detection range (44 nM-1.30 µM) and a low detection limit of 13 nM. Finally, to validate the applicability, this novel fluorescent probe was successfully applied for the quantitative determination of As(III) in rice and water samples.


Assuntos
Arsênio , Grafite , Pontos Quânticos , Corantes Fluorescentes , Alendronato , Espectrometria de Fluorescência/métodos , Íons
2.
Iran J Pharm Res ; 21(1): e126912, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36060907

RESUMO

This study aimed to investigate the synthesis, characterization, and biodistribution of scandium nanoparticles encapsulated within poly (amidoamine) (PAMAM) dendrimers, as well as to estimate the human absorbed dose. It also aimed to examine, in particular, the amine-terminated PAMAM dendrimers in generation 5. Irradiation of the compound in the nuclear reactor resulted in the formation of Sc-radioactive complex nanoparticles. The compound of the dendrimer-Sc3+ was confirmed by the UV-vis spectrometer. The size of the particles was less than 10 nm, and it was assessed using high-resolution transmission electron microscopy (HRTEM) and dynamic light scattering (DLS). The synthesized complex was irradiated by the 3 × 1011 n.cm-2s-1 flux of neutron for 2 h. Mice bearing a breast tumor were employed to assess the therapeutic dose that was delivered by the poly scandium-46-nanoparticles. As opposed to the untreated groups, a single injection of poly phosphate-buffered saline to intratumoral in other groups to deliver a dose of 100 µCi resulted in a statistically significant 39.24% reduction in tumor volume 14 days after injection. After applying the biokinetics data in mice, the human's absorbed dose from scandium-47 encapsulated PAMAM was extrapolated based on animal data. The absorbed doses in critical organs, including the liver, lung, spleen, kidney, and bone, were 0.879, 0.0472, 0.191, 0.107, and 0.155 mGy/MBq, respectively.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121409, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35617832

RESUMO

Herein, water-soluble emissive carbon quantum dots (His-CQDs) were synthesized from pyrolysis of sodium citrate in the presence of histidine under hydrothermal conditions. The as-synthesized His-CQDs were characterized using Fourier transform infrared (FT-IR), fluorescence spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM) techniques. The obtained His-CQDs display a strong emission peak at 534 nm when excited at 476 nm with a high quantum yield (61.8 %). The as-synthesized His-CQDs were applied as a new platform for highly selective determination of Mn(II) based on the fluorescence "turn-on" response with a limit of detection of 1.85 µg L-1 (at 3σ) and a linear range of 3.50-35.5 µg L-1 in aqueous solution. The sensing mechanism of the His-CQDs probe for the detection of Mn(II) was studied via density functional theory (DFT), FT-IR, and EDTA complexation methodology. In addition, His-CQDs were successfully applied to determine the accurate amounts of Mn(II) in whole blood control material. More importantly, the integrating such an efficient sensor with point-of-care technology can enable portable, easy-to-use, and rapid sensing systems for better biological and clinical applications.


Assuntos
Pontos Quânticos , Carbono/química , Histidina , Íons , Limite de Detecção , Manganês , Pontos Quânticos/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Therm Biol ; 104: 103201, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35180977

RESUMO

Hyperthermia, the mild elevation of temperature to 40-45 °C, can induce cancer cell death and enhance the effects of radiotherapy and chemotherapy. Due to the nature of hyperthermia, especially their ability to combine nanotechnology, hyperthermia possesses the potential to open a novel paradigm for the therapeutic strategies. However, achievement of its full potential as a clinically relevant treatment modality has been restricted by its inability to effectively and preferentially heat malignant cells. The main challenge of current hyperthermia treatment is to adequately heat whole volumes of deep-seated tumors without overheating surrounding healthy tissues. So, hyperthermia is under clinical trials (research study with people) and is not widely available. In this Review, we summarize a basic knowledge of hyperthermia before focusing on their applications to the cancer therapy and synthesis. We try to give a comprehensive view of the role of nanomaterials in the designing of hyperthermia-based therapeutic protocols and compare the studies in this field with the purpose of providing a source of helpful information for planning forthcoming hyperthermia researches. However, establishing comparisons between hyperthermia studies is a challenge due to the widely different conditions used by different authors, which, in some cases, is aggravated by the lack of crucial information concerning a certain aspect of the procedure.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas Metálicas/uso terapêutico , Neoplasias/terapia , Humanos , Temperatura
5.
Water Sci Technol ; 84(9): 2557-2577, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34810331

RESUMO

Synthesized Fe0-rGO nanocomposite with ratio of 1/1 (w/w) was prepared and has been used as adsorbent for the removal of Carbamazepine (CBZ) from aqueous solution. The adsorbent was characterized by various techniques such as Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Field Emission Scanning Electron Microscopy (FE-SEM) analyses. Linear experiments were performed to compare the best fitting isotherms and kinetics. The Freundlich isotherm (R2>0.90) and pseudo second order kinetic (R2>0.99) fitted well the experimental data. On the basis of the Langmuir isotherm, the maximum adsorption capacity of Fe0-rGO for CBZ was up to 50 mg g-1 at 30 °C. The pH, adsorbent dose, and initial concentration of CBZ were observed to be the leading parameters that affected the removal of CBZ considering the analysis of variance (ANOVA; p<0.05). The optimum process value of variables obtained by numerical optimization corresponds to pH 3.07, an adsorbent dose of 36.2 mg, an initial CBZ concentration of 5 mg L-1 and at 30.15 °C. The results of optimum conditions reveal that a maximum of 94% removal efficiency can be achieved; whereas, this phenomenon was independent of temperature (p-value>0.05). Moreover, Fe0-rGO can be used to remove diclofenac (DIC) and cetirizine (CTZ) simultaneously. To sum up, the Fe0-rGO is a promising adsorbent not only for the efficient removal of CBZ but also for the reduction of coexisting drugs in aqueous solution.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Adsorção , Carbamazepina , Grafite , Concentração de Íons de Hidrogênio , Ferro , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Anal Bioanal Chem ; 413(25): 6289-6301, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34345948

RESUMO

The present study introduces a novel nanocomposite based on reduced graphene oxide, nitrogen-doped graphene quantum dots, and palladium and silver nanoparticles (rGO/NGQD/AgPd) as an electrocatalyst toward nitrite oxidation reaction. Metal nanoparticles were prepared via a green one-pot photochemical reduction procedure utilizing UV light and NGQD simultaneously as a reducing and directing agent. Formation of the nanocomposite was thoroughly demonstrated by the FT-IR, XRD, Raman, XPS, FE-SEM, and TEM characterization tests. Various electrochemical tests evaluated the efficiency of the prepared sensing platform on the surface of a gold working electrode. Sensitivity and limit of detection (LOD) were calculated to be 0.854 µA.µM-1.cm-2 and 0.052 µM, respectively, from the chronoamperometry data. Finally, the proposed sensor was successfully applied for the determination of nitrite ions in river and mineral water samples as natural water sources.

7.
Mikrochim Acta ; 188(4): 121, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33694010

RESUMO

A voltammetric genosensor has been developed for the early diagnosis of COVID-19 by determination of RNA-dependent RNA polymerase (RdRP) sequence as a specific target of novel coronavirus. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) uses an RdRP for the replication of its genome and the transcription of its genes. Here, the silver ions (Ag+) in the hexathia-18-crown-6 (HT18C6) were used for the first time as a redox probe. Then, the HT18C6(Ag) incorporated carbon paste electrode (CPE) was further modified with chitosan and PAMAM dendrimer-coated silicon quantum dots (SiQDs@PAMAM) for immobilization of probe sequences (aminated oligonucleotides). The current intensity of differential pulse voltammetry using the redox probe was found to decrease with increasing the concentration of target sequence. Based on such signal-off trend, the proposed genosensor exhibited a good linear response to SARS-CoV-2 RdRP in the concentration range 1.0 pM-8.0 nM with a regression equation I (µA) = - 6.555 log [RdRP sequence] (pM) + 32.676 (R2 = 0.995) and a limit of detection (LOD) of 0.3 pM. The standard addition method with different spike concentrations of RdRP sequence in human sputum samples showed a good recovery for real sample analysis (> 95%). Therefore, the developed voltammetric genosensor can be used to determine SARS-CoV-2 RdRP sequence in sputum samples. PAMAM-functionalized SiQDs were used as a versatile electrochemical platform for the SARS-CoV-2 RdRP detection based on a signal off sensing strategy. In this study, for the first time, the silver ions (Ag+) in the hexathia-18-crown-6 carrier were applied as an electrochemical probe.


Assuntos
Teste para COVID-19/instrumentação , Nanotecnologia/métodos , RNA Polimerase Dependente de RNA/genética , SARS-CoV-2/genética , Técnicas Biossensoriais , Dendrímeros , Diagnóstico Precoce , Eletrodos , Humanos , Limite de Detecção , Escarro/virologia , Replicação Viral/genética
8.
Mikrochim Acta ; 187(10): 562, 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32920698

RESUMO

The first dual-modality highly intensive fluorescent and colorimetric nanoprobe for Fe3+ ions and histidine is reported. The carbon dots doped by nitrogen and sulfur (N,S-CDs) prepared by the one-pot hydrothermal method have an excitation/emission wavelength of 320/420 nm with 56% quantum yield. N,S-CDs exhibit strong visible fluorescence with high stability at pH ~ 7.0. The fluorescence intensity of the N,S-CDs is quenched in the presence of Fe3+ ions which are recovered upon the addition of histidine. The addition of Fe3+ ions also induces a color change from yellow to red. Using colorimetric determination, Fe3+ and histidine exhibited linearity in the range 75-675 and 100-375 µmol L-1, respectively, while with fluorometric determinations the dynamic range was 0.1-275 and 0.1-3 µmol L-1 for Fe3+ and histidine, respectively. The limits of detection were 19 nmol L-1 and 0.03 µmol L-1 using fluorometry and 20 µmol L-1 and 24.2 µmol L-1 using colorimetry, for Fe3+ and histidine respectively. The relative standard deviations (n = 5) for Fe3+ (10 µmol L-1) and histidine (1 µmol L-1) using fluorometry were 4.6 and 7.3% and using colorimetry at 100 µmol L-1 of Fe3+ and 150 µmol L-1 of histidine were 3.2 and 5.6%, respectively. The developed fluorometric method was applied for the determination of Fe3+ and histidine in various foods and biological fluid samples as well as intracellular imaging of iron. The accuracy of the method for iron determination was confirmed by the analysis of certified reference materials (wheat flour, tomato leaves, and whole milk powder) and quality control materials (whole milk powder, serum, and urine), whereas for histidine, the accuracy was determined by recovery experiment and independent analysis. Good recovery values in ranges of 92-96% and 94-98% were achieved for Fe3+ and histidine, respectively. Graphical abstract.


Assuntos
Colorimetria/métodos , Fluorometria/métodos , Histidina/química , Ferro/química , Nitrogênio/química , Pontos Quânticos/metabolismo , Enxofre/química , Humanos
9.
Talanta ; 214: 120886, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278407

RESUMO

The recent rapid advances in the synthesis, functionalization and application of nanomaterials have enabled scientists to develop metal nanoclusters (MNCs) stabilized with a variety of scaffolds/protecting ligands including thiols, polymers, proteins, dendrimers and nucleic acids. Considering the unique optical, electronic and physical properties of MNCs, they have been successfully used for the tumor marker biosensing assays. In recent years, the ultrasensitive and accurate detection of tumor markers has been of critical importance for the screening or diagnosis of cancers at their early stages. Nanoclusters have revolutionized the design of biosensors and provided an opportunity for the selective and sensitive determination of tumor markers. Here, we review the synthesis, stabilization and promising applications of fluorescent MNCs, with particular focus on their potential for designing tumor marker biosensors. Finally, the current challenges and future perspectives on the emerging MNC-based biosensors are highlighted as well. Our intended audiences are the broader scientific communities interested in the nanomaterial-based biosensors, and our review paper will, hopefully, open up new horizons for those scientists who manipulae the biological properties of nanoclusters. This review is based on publications available up to January 2020.


Assuntos
Biomarcadores Tumorais/sangue , Técnicas Biossensoriais , Corantes Fluorescentes/química , Nanoestruturas/química , Neoplasias/sangue , Compostos Organometálicos/química , Humanos , Neoplasias/diagnóstico por imagem
10.
J Pharm Biomed Anal ; 179: 112989, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31767223

RESUMO

In continuing our effort focused towards the design and development of nanostructured carbon-based biosensors, herein we report an amine-ionic liquid functionalized reduced graphene oxide (NH2-IL-rGO) immunosensing nanoplatform for the electrochemical detection of human papillomavirus (HPV16) DNA in patients with HPV16-positive head and neck cancer (HNC). The model reaction considered in this work was based on grafting of IL to the surface of GO via its silylanization with 3-chloropropyltrimethoxysilane followed by N-alkylation with sodium imidazole salt. Then, the obtained NH2-IL-rGO was immobilized on a multiwalled carbon nanotube (MWCNT) modified electrode surface and, subsequently used for loading aminated DNA probes via covalent bonds by the glutaraldehyde (GA) reagent. In the presence of anthraquinone-2-sulfonic acid monohydrate sodium salt (AQMS) as a redox-active DNA intercalator, the hybridization of ssDNA probes with the target HPV16 DNA strands (complementary strands) led to a significant increase in the genosensor response. The strong specific interaction between the immobilized probe chain and the complementary chain enabled the detection of the HPV16 gene with the differential pulse voltammetry (DPV) measurements. The described method provided an excellent accuracy and good selectivity, compared to the existing methods. This low-cost genosensor can detect ultralow concentrations of HPV16 DNA with a limit of detection of 1.3 nM (at 3σ) and a linear range of 8.5 nM-10.7 µM. To validate the accuracy and performance of method, the extracted clinical sample DNA was used on the pDNA-modified electrode unlike other works that used PCR products.


Assuntos
DNA Viral/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Neoplasias de Cabeça e Pescoço/diagnóstico , Papillomavirus Humano 16/genética , Líquidos Iônicos/química , Nanotubos de Carbono/química , Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Limite de Detecção , Nanoestruturas/química
11.
Iran J Pharm Res ; 18(2): 569-578, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531042

RESUMO

Novel biodegradable Poly (L-lactic acid) (PLLA) microspheres containing ytterbium were designed for intra-tumoral radiotherapy, especially for radioembolization. 175Yb possess both therapeutic beta and diagnostic gamma radiations. In this work, a process of making ready radiomicrospheres 175Yb (acac)3-loaded PLLA for more consideration has been investigated. The radiomicrospheres were prepared with approximate size of 20-40 µm, and radionuclidic purity > 92%. The radiomicrospheres were stable in-vitro for up to 72 h in normal saline, and also in human serum albumin (HSA). Biodistribution in mice bearing 4T1 tumor showed specific radionuclide uptake over 48 h. Tumor necrosis was also observed at the injection site up to 12 days after injection. These data indicated that 175Yb-PLLA microspheres could be prepared and considered further for radiomicrospheres tumor therapy.

12.
J Pharm Biomed Anal ; 172: 259-267, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078062

RESUMO

In this study, a simple and lable-free voltammetric immunosensor was successfully developed for the ultrasensitive detection of prostate specific antigen (PSA). To do this, multiwalled carbon nanotube (MWCNT)/L-histidine functionalized reduced graphene oxide (His-rGO) was demonstrated as a bifunctional nanoplatform for covalently attaching thionine redox indicator and anti-PSA antibody (Ab). The MWCNT enhanced electrical conductivity and facilitated the electron transfer between thionine and the glassy carbon electrode. While, the presence of anti-PSA antibody blocked the electron transfer of thionine and decreased redox signals. The principle response of proposed immunosensor was based on the selective interaction of PSA with thionine-NH2-GO-COOH-Ab. This selective interaction led to further decrease of response current of attached electrochemical probe. The liner calibration curve for tumor marker determination was 10 fg mL-1-20 ng mL-1 (R2 = 0.996). Under optimized conditions, the immunosensor was able to selectively detect PSA with a limit of detection (LOD) of 2.8 fg mL-1 at 3σ. The relative standard deviations (RSDs) for single-electrode repeatability and electrode-to-electrode reproducibility were less than 2.9% and 5.7% (n = 5), respectively. Furthermore, the as-proposed immunosensor showed excellent performance in detection of PSA in the human serum and saliva samples, which implies that the current strategy has a promising feature for the clinical assessment of tumor marker status in patients with prostate cancer.


Assuntos
Técnicas Biossensoriais/instrumentação , Detecção Precoce de Câncer/instrumentação , Imunoensaio/instrumentação , Nanotubos de Carbono/química , Neoplasias da Próstata/diagnóstico , Biomarcadores Tumorais/metabolismo , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Grafite/química , Humanos , Limite de Detecção , Masculino , Nanopartículas Metálicas/química , Óxidos/química , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismo , Reprodutibilidade dos Testes
13.
J Pharm Biomed Anal ; 172: 223-229, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060035

RESUMO

A highly selective, sensitive, and rapid colorimetric sensor for the determination of dopamine (DA) was developed using the color change of S-doped carbon dots functionalized gold nanoparticles (S-CDs@Au NPs). The base of the method is the formation of a complex between the amine groups of dopamine with carboxylic groups of S-CDs@Au NPs followed by their aggregation with Fe3+ ions which acts as the linkers causing a red shift from 520 to 670 nm in the localized surface plasmon peak of S-CDs@Au NPs. The ratio of absorbance intensity at 670 nm to 520 nm was monitored as the analytical signal for determination of dopamine. The parameters affecting the analytical signal including reaction time, solution pH, the concentration of Au NPs and concentration of Fe3+ were optimized. At optimized conditions, the calibration curve was linear in the concentration range of 0.81-16.80 µM of dopamine. The detection and quantification limits were 0.23 µM and 0.77 µM, respectively. The intra-day and inter-day relative standard deviation (RSDs) at 5.0 µM of DA were 3.9% and 5.6%, respectively (n = 5). The applicability of the method for determination of DA in dopamine ampoule, urine and serum human samples was investigated.


Assuntos
Carbono/química , Dopamina/química , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Ressonância de Plasmônio de Superfície/métodos
14.
Mater Sci Eng C Mater Biol Appl ; 97: 679-687, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678956

RESUMO

In this study, a high-performance biosensing nanoplatform based on amidoxime-modified polyacrylonitrile nanofibers decorated with Ag nanoparticles (AgNPs-PAN-oxime NFs) is described. The AgNPs-PAN-oxime NFs were prepared by the combination of electrospinning technique and chemical modification of nitrile group in the PAN. The proposed signal amplifiying nanoplatform was applied in the fabrication of an electrochemical aptasensor for the sensitive detection of CA 125 based on aptamer-cDNA duplex and target induced strand displacement recognition mechanism. The aptasensing interface offers high sensitivity and selectivity for detection of tumor marker due to inherent advantages such as high specific surface area of NFs, good conductivity by doping AgNPs into the polymer NFs and especially the ideal selectivity of anti CA 125 aptamer to its target. The electrochemical aptasensor revealed a wide dynamic linear range (DLR) from 0.01 to 350 U mL-1 with a correlation coefficient of 0.991 and limit of detection (LOD) of 0.0042 U mL-1. Additionally, the designed aptasensor showed acceptable selectivity, reproducibility, repeatability and stability. The satisfactory results for determination of CA 125 in serum samples compared to ELISA method (p-value > 0.05) indicated the potential application of aptasensor in clinical monitoring of tumor biomarker for early diagnosis and management of ovarian cancer.


Assuntos
Resinas Acrílicas/química , Aptâmeros de Nucleotídeos/química , Antígeno Ca-125/sangue , Técnicas Eletroquímicas/métodos , Nanofibras/química , Neoplasias Ovarianas/diagnóstico , Técnicas Biossensoriais/métodos , Eletrodos , Feminino , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Oximas/química , Reprodutibilidade dos Testes , Prata/química
15.
Biol Trace Elem Res ; 190(1): 262-272, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30343481

RESUMO

In the present study, for the first time, the magnetic graphene oxide was simultaneously functionalized and reduced with the aim of imidazole-based L-histidine amino acid (rGO/Fe3O4-histidine). The prepared nanocomposite was characterized by field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, Raman spectroscopy, and vibrating sample magnetometer. The synthesized rGO/Fe3O4-histidine nanosheets were implied for solid phase extraction of ultra-trace amounts of Zn2+, Cu2+, and Mn2+ from biological samples prior to ICP-OES determination. The calibration curves were linear in the concentration ranges of 0.4-182.0, 0.4-215.0, and 0.2-168.5 µg L-1 for Zn2+, Cu2+, and Mn2+, respectively. The limits of detection were 0.12, 0.10, and 0.04 µg L-1 for Zn2+, Cu2+, and Mn2+, respectively. The relative standard deviations (RSDs) at 50.0 µg L-1 for single-sorbent repeatability and sorbent-to-sorbent reproducibility were less than 6.7 and 9.2% (n = 5), respectively. The accuracy of the method was confirmed by the analysis of a serum quality control material (QCM, Seronorm™ Human Serum REF NO 203105) and hair certified reference material (CRM, Human Hair IAEA-086).


Assuntos
Antioxidantes/química , Grafite/química , Histidina/química , Oligoelementos/química , Cobre/química , Manganês/química , Extração em Fase Sólida , Espectrometria por Raios X , Análise Espectral Raman , Zinco/química
16.
J Med Phys ; 43(3): 173-178, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30305775

RESUMO

PURPOSE: This investigation focuses on biodistribution of irradiated dendrimer encapsulated ytterbium-175 (175Yb) and to estimate the absorbed dose from intravenous injection of PAMAM encapsulated 175Yb to human organs. METHODS: A dendrimer compound containing an average of 55 Yb+3 ions per dendrimer was prepared and irradiated with neutrons for 2h at 3×1011 n.cm-2s-1 neutron flux. The resulting mixture was injected into a group of tumor bearing mice and the mice were excised, weighed and counted at certain times to study the biodistribution. The human organs absorbed dose was assessed by MIRD schema and MCNP simulation. RESULTS: The specific activity and radiochemical purity of the irradiated nano-composite were 7MBq/mg and >99% respectively. The rapid up take of dendrimer was in liver, lung, and, spleen. MIRD and MCNPX were applied for dose estimation. The human absorbed dose in liver, lung, spleen, kidney and bone that simulated by MCNP are 1.266, 0.8081, 0.8347, 0.03979 and 0.01706 mGy/MBq respectively and these values for MIRD schema are 1.351, 0.73, 1.03, 0.039, and 0.0097 mGy/MBq respectively. CONCLUSION: The results showed that 175Yb-PAMAM nano-radiopharmaceutical has potential of application for liver and lung tumors.

17.
J Labelled Comp Radiopharm ; 61(8): 586-594, 2018 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-29644706

RESUMO

Radioembolization with radioactive microspheres has been an effective method for the treatment of liver lesions. The aim of this study was to prepare carrier-free 188 Re loaded poly (L-lactic acid) (PLLA) microspheres through 188 Re sulfide colloidal nanoparticles (188 Re-SC nanoparticles). The formation of 188 Re-SC nanoparticles was confirmed by ultraviolet-visible spectrophotometry. The labeling yield of 188 Re-SC nanoparticles was verified using the RTLC method. Effects of synthesis parameters on morphology and size of prepared 188 Re-sulfide colloidal-PLLA microspheres (188 Re-SC-PLLA microspheres) were studied by scanning electron microscopy. In vitro stability of 188 Re-SC-PLLA microspheres was investigated in normal saline at room temperature and in human serum at 37°C. In vivo distribution studies and gamma camera imaging were performed in healthy BALB/c mice. The microspheres could be prepared with sizes between 13 and 48 µm (modal value 29 µm) and radiolabeling efficiency >99%. After incubation, the microspheres were found stable in vitro up to 72 hours. The biodistribution after intravenous injection in healthy BALB/c mice showed high accumulation in lung as a first capture pathway organ for microsphere followed by great retention over 48 hours for these microspheres. These data show that 188 Re-SC-PLLA microspheres are suitable candidate for clinical studies.


Assuntos
Embolização Terapêutica/métodos , Microesferas , Nanopartículas/química , Poliésteres/química , Poliésteres/uso terapêutico , Radioisótopos/uso terapêutico , Rênio/uso terapêutico , Sulfetos/química , Animais , Coloides , Camundongos , Camundongos Endogâmicos BALB C , Poliésteres/metabolismo , Poliésteres/farmacocinética , Distribuição Tecidual
18.
IEEE Trans Nanobioscience ; 15(6): 549-554, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27824577

RESUMO

The aim of this study is preparation of dendrimer encapsulated ytterbium-175 radio-nanoparticles and investigation of the compound chemical characteristic before and after the neutron irradiation and also study the in vivo biodistribution for targeted radiopharmaceutical dose delivery to solid tumors. For preparation of dendrimer-metal nanocomposite, a dendrimer compound containing an average of 55 Yb+3 ions per dendrimer was prepared. The synthesized encapsulated ytterbium irradiated by neutron for 2 h at 3×1011 n.cm [Formula: see text] neutron flux. The resulting mixture was injected into 2 separate groups of tumor bearing mice. One group were injected intravenously and the other group were injected directly in tumor and were excised, weighed and counted at certain times to study the biodistribution and to compare the tumor treatment and the leakage of the radiopharmaceutical to non-target organs. The formation of dendrimer-Yb3+complex was confirmed by UV-vis spectrometer. High-resolution transmission electron microscopy (HRTEM) and Dynamic Light Scattering (DLS) results showed a particle size of less than 10 nm. The specific activity and radio-ytterbium purity of the irradiated nano-composite were as follows: 7 MBq/mg and >95%. The measured radiochemical purity by Instant Thin Layer Chromatography (ITLC) was more than 99%. In intravenous injection the complex showed rapid up take in liver, spleen, and lung, while accumulation in other organs was insignificant. In tumor direct injection the average size of the tumor mass in mice was reduced by 30%.


Assuntos
Dendrímeros , Portadores de Fármacos , Neoplasias Experimentais/metabolismo , Itérbio , Animais , Linhagem Celular Tumoral , Dendrímeros/química , Dendrímeros/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Feminino , Fígado/química , Fígado/metabolismo , Pulmão/química , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Baço/química , Baço/metabolismo , Distribuição Tecidual , Itérbio/química , Itérbio/farmacocinética
19.
J Environ Health Sci Eng ; 12(1): 7, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24397886

RESUMO

The effects of varying operating conditions on metals removal from aqueous solution using a novel platinum nanopartcles/Zeolite-4A adsorbent are reported in this paper. Characterization of the adsorbent showed successful production of platinum nanopartcles on Zeolite-4A using 3 Wt% platinum. The effects of operation conditions on metals removal using this adsorbent were investigated. The optimal metals adsorption was observed at pH 7, 0.1 g/10 mL dosage and 30 min contact time. Sorption data have been interpreted in terms of Langmuir and Freundlich isotherms.

20.
J Labelled Comp Radiopharm ; 56(1): 12-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24285135

RESUMO

Gold nanorods (GNRs) can be used in various biomedical applications; however, very little is known about their in vivo tissue distribution by radiolabeling. Here, we have developed a rapid and simple method with high yield and without disturbing their optical properties for radiolabeling of gold rods with iodine-131 in order to track in vivo tissue uptake of GNRs after systemic administration by biodistribution analysis and γ-imaging. Following intravenous injection into rat, PEGylated GNRs have much longer blood circulation times.


Assuntos
Nanopartículas Metálicas/química , Compostos Radiofarmacêuticos/farmacocinética , Animais , Ouro/química , Radioisótopos do Iodo/química , Radioisótopos do Iodo/farmacocinética , Marcação por Isótopo , Nanopartículas Metálicas/análise , Polietilenoglicóis/química , Compostos Radiofarmacêuticos/química , Ratos , Distribuição Tecidual
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