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1.
Dev Comp Immunol ; 102: 103477, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31470020

RESUMO

Two continuous macrophage cell lines (LCM07 and LCM10) were established for the first time from the head kidney of the marine fish large yellow croaker (Larimichthys crocea). To date, both cell lines have been subcultured for more than 100 passages in 12 months. Notably, the LCM07 and LCM10 cells have distinct morphology and immune function. LCM07 cells showed strong contact inhibition in crowded conditions, while this was not observed in the LCM10 cells because they could grow in an overlapping manner. Correspondingly, LCM10 cells were slenderer than LCM07 cells. LCM07 cells had stronger phagocytic ability than LCM10 cells, while LCM10 cells had stronger respiratory burst activity after incubation with lipopolysaccharide (LPS) and phorbol ester (PMA). LCM07 cells had stronger Escherichia coli killing ability than LCM10 cells. The mRNA of macrophage markers, namely that of CD11b, CD114, CD68, CD86, CD209, and CD163, were all expressed in primary macrophages as well as the two cell lines. The mRNA expression levels of selected inflammatory cytokines, namely interleukin (IL)-1ß, IL-8, and tumor necrosis factor (TNF)α, were all upregulated after incubation with LPS. LPS also regulated key components of the mitogen-activated protein kinase (MAPK) signaling pathway, i.e., p38, ERK (extracellular signal-regulated kinase), and JNK (Jun N-terminal kinase) and their phosphorylated forms. Arachidonic acid (ARA) downregulated the LPS-induced upregulation of IL-1ß, IL-8, and TNFα, revealing that LCM07 and LCM10 cells are useful for studying nutritional immunity. In conclusion, two distinct macrophage cell lines have been established for the first time from the head kidney of marine fish, which could be useful for studying immunity and nutritional immunity.

2.
Bioresour Technol ; 295: 122243, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622918

RESUMO

Rice husk is a widespread agriculture waste in rice-farming country. High silica content in rice husk prevent its efficient utilization. So in this work, concept of poly-generation was introduced to improve its utilization value. This study provided CO-rich syngas, phenol-abundant bio-oil, high-adsorption porous carbon and amorphous SiO2 as four end products for first time via combination of acid washing and activated carbon catalyst. Specifically, acid washing effectively decreasedsoluble ash, which altered pyrolysis paths, increased volatiles release and reduced impurities in bio-char. After catalytic pyrolysis, phenol content of 65.56% and CO of 56.09 vol% were detected in bio-oil and syngas from AWRH. For solid products, acid washing benefited both bio-char and silica. A low-cost porous carbon with developed pores and rich surface functional groups was prepared for water absorption. And high purity amorphous SiO2 was recycled from alkali etching solution. Finally, a green process with no waste emission was proposed.


Assuntos
Oryza , Fenol , Adsorção , Biomassa , Fenóis , Óleos Vegetais , Polifenóis , Porosidade , Pirólise , Dióxido de Silício
3.
Cancer Res Treat ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671936

RESUMO

Purpose: To investigate the prognostic impact of EBV-miR-BHRF1-1 with chronic lymphocytic leukemia (CLL) as well as role of EBV-miR-BHRF1-1 in p53 gene. Materials and Methods: Quantitative reverse transcription-PCR (qRT-PCR) and western blotting (WB) were used to quantify EBV-miR-BHRF1-1 and p53 expression in cultured CLL. Results: p53 aberration was associated with higher expression level of Epstein-Barr virus (EBV)-microRNA (miRNA, miR)-BHRF1-1 (p<0.001) which was also an independent prognostic marker for overall survival (OS) (p=0.028; HR 5.335 [1.193, 23.846]) in 97 newly-diagnosed CLL patients after adjusted with CLL-international prognostic index (CLL-IPI). We identified EBV-miR-BHRF1-1 as a viral miRNA regulator of p53. EBV-miR-BHRF1-1 repressed luciferase reporter activity by specific interaction with the seed region within the p53 3' untranslated region. Discordance of p53 messenger RNA and protein expression was associated with high EBV-miR-BHRF1-1 levels in CLL patients and cell lines. EBV-miR-BHRF1-1 inhibition upregulated p53 protein expression, induced cell cycle arrest and apoptosis and decreased cell proliferation in cell lines. EBV-miR-BHRF1-1 mimics downregulated p53 protein expression, decreased cell cycle arrest and apoptosis, and induced cell proliferation in cell lines. Conclusion: This study supported a role of EBV-miR-BHRF1-1 in p53 regulation in vitro. Our results support the potential of EBV-miR-BHRF1-1 as a therapeutic target in EBV-associated CLL with p53 gene aberration.

4.
Opt Express ; 27(19): 27229-27241, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674588

RESUMO

An accurate model for the silicon refractive index including its temperature and wavelength dependence is critically important for many disciplines of science and technology. Currently, such a model for temperatures above 22°C in the optical communication bands is not available. The temperature dependence in the spectral response of integrated echelle grating filters made in silicon-on-insulator is solely determined by the optical properties of the slab waveguide, making it largely immune to dimensional uncertainties. This feature renders the echelle filters a reliable tool to evaluate the thermo-optic properties of silicon. Here we investigate the temperature dependence of silicon echelle filters for the wavelength range of both O and C bands, measured between 22°C to 80°C. We show that if a constant thermo-optic coefficient of silicon is assumed for each band, as is common in the literature, the predictions show an underestimate of up to 10% in the temperature-induced channel wavelength shift. We propose and assess a model of silicon refractive index that encompasses both the wavelength and temperature dependence of its thermo-optic coefficients. We start from literature data for bulk silicon and further refine the model using the echelle filter measurement results. This model is validated through accurate predictions of device channel wavelengths and their temperature dependence, including the quadratic term, over a wide wavelength and temperature range. This work also demonstrates a new high-precision method for characterizing the optical properties of a variety of materials.

5.
Chem Commun (Camb) ; 55(96): 14458-14461, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31728469

RESUMO

A detailed mechanism study on the anion ligand promoted selective C-H bond fluorination is reported. The role of the anion ligand has been clarified by experimental evidence and DFT calculations. Moreover, the nitrate promoted C-F bond reductive elimination enabled a selective C-H bond fluorination of various symmetric and asymmetric azobenzenes to access diverse o-fluoroanilines.

6.
Biotechnol Lett ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776751

RESUMO

OBJECTIVES: Previously, we have found that the matrix attachment region (MAR) may confer a 'distance effect' on transgene expression. This work aims to systematically explore the increased transgene expression in transfected Chinese hamster ovary (CHO) cells due to the characteristics of MAR and its mechanism. RESULTS: Compared with the control vector, 500 and 1000 bp DNA distances between MAR and the cytomegalovirus promoter can increase transgene expression by 1.77- and 1.56-fold, respectively. Meanwhile, transgene expression was not affected when 2000 and 2500 bp spacer DNAs were inserted, but a declining trend was observed when a 1500 bp spacer DNA was inserted. The vector containing a 500 bp DNA distance significantly increased the expression of the enhanced green fluorescent protein, and this increase was not related to transgene copy numbers. CONCLUSIONS: A short DNA distance-containing MAR confers high transgene expression level in transfected CHO cells, but a distance threshold does not exist in the vector system.

7.
Opt Lett ; 44(23): 5840-5843, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31774793

RESUMO

Miniaturized silicon photonics spectrometers capable of detecting specific absorption features have great potential for mass market applications in medicine, environmental monitoring, and hazard detection. However, state-of-the-art silicon spectrometers are limited by fabrication imperfections and environmental conditions, especially temperature variations, since uncontrolled temperature drifts of only 0.1°C distort the retrieved spectrum precluding the detection and classification of the absorption features. Here we present a new strategy that exploits the robustness of machine learning algorithms to signal imperfections, enabling recognition of specific absorption features in a wide range of environmental conditions. We combine on-chip spatial heterodyne Fourier-transform spectrometers and supervised learning to classify different input spectra in the presence of fabrication errors, without temperature stabilization or monitoring. We experimentally show the differentiation of four different input spectra under an uncontrolled 10°C range of temperatures, about $ 100\times $100× increase in operational range, with a success rate up to 82.5% using state-of-the-art support vector machines and artificial neural networks.

8.
J Immunol ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748346

RESUMO

Coxsackievirus B is a common cause of viral myocarditis and pancreatitis. IL-17A is intensively involved in the pathogenesis of viral myocarditis. Whether IL-17A plays a role in Coxsackievirus B-induced pancreatitis, characterized by acinar cell destruction and immune infiltration, remains largely unknown. We found a significant, but transient, increase of IL-17A expression and γδT influx in the pancreas of C57BL/6J mice within 3 d following CVB3 infection. The pancreatic IL-17A was mainly produced by Vγ4 γδ T cells, to a lesser extent by CD4+ Th17 cells. IL-17A-/- and TCRδ-/- mice both reduced their susceptibility to CVB3 infection and pancreatitis severity when compared with the wild-type mice, without altering viral load. mAb depletion of Vγ4γδ T cells significantly improved mice survival and pancreatic pathology via decreasing Th17 expansion and neutrophil influx into the pancreas compared with isotype-treated mice. Transfer of Vγ4γδ T cells from wild-type, but not IL-17-/-, mice reconstituted TCRδ-/- mice to produce IL-17 and develop pancreatitis to the level of wild-type mice during CVB3 infection, indicating γδ T IL-17A is required for the onset of viral pancreatitis. IL-23 was robustly induced in the pancreas within the first day of infection. Administration of exogenous rIL-23 to mice increased CVB3 pancreatitis through in vivo expansion of IL-17+γδT17 cells at 12 h postinfection. Our findings reveal a key pathogenic role for early-activated γδT17 cells in viral pancreatitis via promoting neutrophil infiltration and Th17 induction. This IL-23/γδT17/neutrophil axis is critically involved in the onset of CVB3 pancreatitis and represents a potential treating target for the disease.

9.
Bioorg Med Chem Lett ; : 126774, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31685339

RESUMO

In continuation of our program to discover new potential antifungal agents, a series of amide and imine derivatives containing a kakuol moiety were synthesized and characterized by the spectroscopic analysis. By using the mycelium growth rate method, the target compounds were evaluated systematically for antifungal activities in vitro against four plant pathogenic fungi, and structure-activity relationships (SAR) were derived. Compounds 7d, 7e, 7h, 7i and 7r showed obvious inhibitory activity against the corresponding tested fungi at 50 µg/mL. Especially, compounds 7e and 7r displayed more potent antifungal activity against B. cinerea than that of thiabendazole (a positive control). Moreover, compound 7e also exhibited good activity against A. alternata with EC50 values of 11.0 µg/mL, and the value was slightly superior to that of thiabendazole (EC50 = 14.9 µg/mL). SAR analysis showed that the ether group was a highly sensitive structural moiety to the activity and the type as well as position of substituents on benzene ring could make some effects on the activity.

11.
Phys Chem Chem Phys ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31728475

RESUMO

The boundary between a capacitor and a battery is vague for layered transition metal sulfides, especially when it comes to TiS2 with a multi-phase transition process. In this work we analyzed both the quasi-static process and dynamic process of K+ storage in TiS2 with carbonate based electrolytes, which proved to be an intercalation pseudocapacitive behavior.

12.
Psychol Med ; : 1-12, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31685046

RESUMO

BACKGROUND: The microbiota-gut-brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients. METHODS: We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD. RESULTS: The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890. CONCLUSIONS: The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.

13.
Scand J Immunol ; : e12851, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733121

RESUMO

Acute liver injury is a common pathological basis for a variety of acute liver diseases in the clinic, which can eventually lead to liver fibrosis and even liver failure. In this study, we found that T cell Ig and mucin domain protein 3 (Tim-3) and TLR4 receptors play important roles in CCl4-induced acute liver injury. Tim-3 is a negative regulator that is expressed by T cells and macrophages. Using antibodies against Tim-3 (anti-Tim-3 Ab), we studied the Tim-3 signal in an animal model of acute liver injury and found that a large number of inflammatory factors were upregulated. In vitro experimental data shown that anti-Tim-3 Ab treatment increased interferon-É£ production by concanavalin A (ConA) stimulated spleen T cells, and we found that the expression level of interleukin (IL)-6 was increased in a macrophage/spleen T cell coculture system, while administration of galectin-9 (Gal-9, a Tim-3 ligand) reduced the IL-6 production. This indicates that the importance of the Tim-3/Gal-9 signaling pathway in maintaining hepatic homeostasis. The Tim-3 signaling pathway inhibits TLR4-mediated NF-κB activity, and an anti-Tim-3 Ab does not affect the liver injury in TLR4-deficient mice. Regulation between Tim-3 and-TLR4 determines the severity of liver damage. The negative regulation of Tim-3 reflects the protective mechanisms of patients with impaired liver function, and these results provide important information about innate and adaptive responses in the regulation of liver damage. This finding is potentially important for the study of early liver injury.

14.
J Clin Lab Anal ; : e23096, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691380

RESUMO

BACKGROUND: Identification of biomarkers for acute myeloid leukemia (AML) is important for treating this malignancy. Recent studies have reported that microRNAs (miRNAs) are stably detectable in the blood/plasma and can be used as biomarkers for various types of cancer including AML. The aim of this study was to analyze miR-223 level in serum as a potential indicator for AML diagnosis and prognosis prediction. METHODS: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the levels of miR-223 in the serum samples from 131 patients and 70 healthy individuals. RESULTS: The results revealed that serum miR-223 was underexpressed in AML patients, particularly those in intermediate and unfavorable cytogenetic risk groups. Further analysis revealed that serum miR-223 could yield a receiver operating characteristic (ROC) area under the curve (AUC) of 0.849 with 83.2% sensitivity and 81.4% specificity. Moreover, a significant increase in serum miR-223 level was observed in AML subjects after their treatment. Reduced serum miR-223 level was highly associated with aggressive clinical variables and shorter survival of patients. Furthermore, miR-223 expression was identified to be an independent prognostic predictor of worse overall survival. CONCLUSION: In conclusion, miR-223 may be a reliable diagnostic and prognostic biomarker for AML.

15.
Med Teach ; : 1-7, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718353

RESUMO

Background and aim: The increasing opportunities for medical students to participate in international electives may improve students' professionalism and cultural competence. However, the students' overall experiences may be unpredictable, unstructured and lack supervision. There is scant evidence with respect to their learning outcomes. These reflections demonstrate that short-term supervised elective can provide students with structured learning experiences to achieve specific learning objectives.Methods: We carried out daily debriefs and a weekly summary with seven Curtin Medical School students from Perth, Australia during an 18-days supervised elective in the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. The daily debriefs and the weekly summary in different disciplines become the content of the reflections discussed in this article.Results: The main themes identified in the feedback were as follows: Skills in history taking and physical examination; clinical reasoning; diagnosis and management of diseases rarely seen in Australia; awareness of clinical ethics; merits and demerits of different systems of healthcare; sensitivity to issues in doctor-patient relationships; work ethics; enhancement of cultural competence; and personal development.Conclusions: These reflections provide insight into how overseas electives may be structured to improve students' clinical reasoning skills in this hospital. These students achieved their learning outcomes under joint supervision from both institutions. The clinical skills learned from these experiences enhanced the students' professionalism and cultural competence, giving students the opportunities to appreciate the multitude healthcare model of bio-psycho-social-political-economical-spiritual dimensions.

16.
J Pharm Biomed Anal ; : 112975, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735472

RESUMO

Ischemic stroke is the main cause of disability and mortality worldwide. 10-O-(N N-dimethylaminoethyl)-ginkgolide B methane-sulfonate (XQ-1 H) is a novel drug based on the remedial approach for ischemic stroke. Clopidogrel, a widely used anti-platelet drug, is often co-prescribed in the clinic. In this study, we established an UPLC-MS/MS spectrometry method for the determination of XQ-1H and investigated the pharmacokinetic effect of clopidogrel on XQ-1H in rats subjected to middle cerebral artery occlusion (MCAO). Meanwhile, the anti-apoptotic and neuroprotective effects of XQ-1H and its combination with clopidogrel were also studied. The results revealed that XQ-1H and its combination with clopidogrel abridged brain infarct volume, cerebral edema and alleviated neurological dysfunction caused by cerebral ischemic reperfusion injury. Further study demonstrated that XQ-1H combined with clopidogrel lessened TUNEL positive cells, up-regulated bcl-2 expression notably and down-regulated bax expression as compared to both XQ-1H and clopidogrel individually. In addition, a rapid, sensitive UPLC-MS/MS method was developed to quantify the concentration of XQ-1H in MCAO/R rats. Our pharmacokinetic results showed that clopidogrel significantly increased the exposure of XQ-1H, increased the peak plasma concentration (Cmax), area under the curve (AUC) and slowed elimination of XQ-1H in the co-administered group. Besides, for further exploring which CYP450 isoforms are involved in the XQ-1H metabolism, XQ-1H was incubated in human liver microsomes (HLMs) system with or without P450 isoform-selective inhibitors. Our results revealed that clopidogrel altered pharmacokinetics of XQ-1H potentially and subsequently enhanced the pharmacological effect of XQ-1H. Moreover, XQ-1H could be applied as an efficacious neuroprotective agent for ischemic stroke because of its considerable effect on averting neuronal apoptosis.

17.
J Agric Food Chem ; 67(43): 12094-12104, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566978

RESUMO

A large portion of Maillard reaction products (MRPs) cannot be absorbed in the upper gut and therefore may be further decomposed and utilized by colonic microbiota (CM). This work reported the stability of UV-absorbent MRPs, fluorescent MRPs and peptide-bound N(ε)-(carboxymethyl)-lysine (CML) in high molecular weight (HMW, >10 kDa), medium molecular weight (MMW, 1-10 kDa), and low molecular weight (LMW, <1 kDa) gastrointestinal digests of glyoxal-glycated casein in the presence of CM. Fluorescent MRPs showed high stability, whereas UV-absorbent MRPs may be partially decomposed. A higher depletion rate of CML was found in the LMW fraction (38.7%) than in the MMW (21.7%) and HMW (9.6%) fractions. The 16S rRNA sequencing results revealed both beneficial and detrimental changes in CM composition induced by the glycated fractions. Generation of short-chain and branched-chain fatty acids in fermentation solutions with glycated fractions was significantly suppressed compared with that in fermentation solution with unglycated digests. This work revealed the possible interplay between peptide-bound MRPs and CM.

18.
Free Radic Biol Med ; 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31626947

RESUMO

We found recently that benzohydroxamic acid (BHA) could detoxify the chlorinated quinoid carcinogens via an unusual Lossen rearrangement reaction. However, it is not clear what would happen when the nitrogen hydrogen of BHA was substituted with methyl and other alkyl groups. Here we show that N-methyl benzohydroxamic acid (N-MeBHA, a simple model compound for the classic iron-chelator deferoxamine, which is a typical N-alkyl trihydroxamic acid) could react with 2,5-dichloro-1,4-benzoquinone (DCBQ) to form a relatively stable initial carbon-oxygen bonding conjugation intermediate CBQ-O-N-MeBHA. However, the major final product was identified, unexpectedly, as a carbon-nitrogen bonding conjugate CBQ(OH)-N(CH3)-COAr, which is the rearranged isomer of CBQ-O-N-MeBHA. Interestingly, a new 18-line nitrogen-centered radical and a carbon-centered quinone ketoxy radical were observed by the ESR spin-trapping method, which was further confirmed by HPLC-MS and 15N-isotope labeling methods. We further found that both new DNA adducts and DNA strand breaks could be produced by the reactive nitrogen-centered radical. Taken together, we propose that the reaction between DCBQ and N-MeBHA was not via the Lossen rearrangement, but rather through a novel radical homolysis and recoupling pathway. Analogous results were observed for other chlorinated quinones and N-alkyl hydroxamic acids including the widely-used trihydroxamate iron-chelating drug deferoxamine. This represents the first report of unexpected radical pathway for the reaction between chlorinated quinones and N-alkyl hydroxamic acids under normal physiological conditions, which may have broad biological and environmental significance for future study of carcinogenic chloroquinones and hydroxamic acid drugs.

19.
Infect Immun ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31611271

RESUMO

Human α-defensins are 3-5 KDa, disulfide-bridged peptides with a multiplitude of anti-microbial activities and immunomodulatory functions. Recent studies show that human enteric α-defensin 5 (HD5), a host defense peptide important for intestinal homeostasis and innate immunity, aids the highly infectious enteropathogen Shigella to breach the intestinal epithelium in vitro and in vivo Whether or not and how HD5 influences Shigella infection of resident macrophages following its invasion of the epithelial epithelium remains poorly understood. Here we report that HD5 greatly promoted phagocytosis of Shigella by macrophages by targeting the bacteria to enhance bacterium-to-cell contacts in a structure- and sequence-dependent fashion. Subsequent intracellular multiplication of phagocytosed Shigella led to massive necrotic cell death and release of the bacteria. HD5-promoted phagocytosis of Shigella was independent of the status of the type 3 secretion system. Further, HD5 neither inhibited nor enhanced phagosomal escape of Shigella Collectively, these findings confirm a potential pathogenic role of HD5 in Shigella infection of not only epithelial cells but also macrophages, illuminating how an enteropathogen exploits a host protective factor for virulence and infection.

20.
Inorg Chem ; 58(21): 14325-14330, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31622085

RESUMO

The photoluminescence of lanthanide ions inside fullerenes is usually very weak due to the quenching effect of the fullerene cage. In the case of Er@C82, the near-infrared emission from the Er3+ ion is completely quenched by the C82 fullerene cage. It remains challenging to turn on the photoluminescence of Er@C82 and other monometallofullerenes. In this work, we adopt a covalent modification strategy to alter the electronic structure of the fullerene cage for sensitizing the near-infrared emission of Er3+ ions in metallofullerenes Er@C2n (2n = 72, 76, and 82). After covalent modification with trifluoromethyl, phenyl, or dichlorophenyl groups, the erbium metallofullerenes exhibit photoluminescence at 1.5 µm, which is the characteristic emission of the Er3+ ion. Particularly, the otherwise nonfluorescent metallofullerene Er@C82 is transformed into fluorescent derivatives by using this strategy. The photoluminescence from the Er3+ ion is ascribed to energy transfer from the fullerene cage to the Er3+ ion. According to theoretical calculations, the sensitization of the Er3+ ion by the fullerene cage is associated with the large HOMO-LUMO gap and the closed-shell electronic structure of the metallofullerene derivatives. This work provides useful guidance for the design and synthesis of new fluorescent metallofullerenes.

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