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1.
Dalton Trans ; 53(15): 6601-6608, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38512315

RESUMO

Multi-functionalised nano-platforms based on persistent-luminescence nanoparticles (PLNPs) have attracted considerable attention for biomedical applications owing to their lack of background noise and suitability for in vivo imaging without the need for in situ excitation. However, nano-platforms based on PLNPs for continuous photodynamic therapy (PDT) are currently lacking. Herein, we report a nano-platform (LiGa4.99O8:Cr0.01/IrO2, LGO:Cr/IrO2) prepared using PLNPs (LiGa4.99O8:Cr0.01, LGO:Cr) covalently bonded with iridium oxide nanoparticles (IrO2 NPs), producing near-infrared (NIR) persistent luminescence, "afterglow" PDT and photo-thermal therapy (PTT) effects. The LGO:Cr/IrO2 not only exhibits NIR-persistent luminescence at 719 nm and a PTT effect under 808 nm irradiation but also a continuous "afterglow" PDT effect without the need for in situ excitation owing to persistent energy transfer from LGO:Cr to the IrO2 NPs, in turn generating reactive oxygen species (ROS). This multi-functional nano-platform is expected to further promote the application of PLNPs in tumour treatment.


Assuntos
Nanopartículas , Neoplasias , Humanos , Luminescência , Diagnóstico por Imagem
2.
PeerJ ; 11: e16435, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025684

RESUMO

Introduction: English argumentative writing (EAW) is a 'problem-solving' cognitive process, and its relationship with critical thinking has drawn attention in China. This is because fostering EAW proficiency is a crucial element but a challenging task for Chinese high school English teaching and learning. The present study examined how critical thinking is related to Chinese high school students' EAW performance. The study identified eight critical thinking disposition (CTD) subscales and aims to determine whether EAW and CTD are correlated. Methods: A questionnaire modified from the Chinese Version Critical Thinking Disposition Inventory (CTDI-CV) and the Evaluation Criteria for English Argumentative Writing (ECEAW) were employed in this study. Both instruments were administered to 156 students from Grade 12. A purposive sampling of high school students was used in this study. Student EAW performance was scored by two experts based on the Evaluation Criteria for English Argumentative Writing. Results: A significant relationship was found between students' CTD and EAW abilities. Furthermore, among the eight CTD subdispositions, cognitive maturity, truth-seeking, analyticity, and justice were found to be positively correlated with EAW, and they all were found to be the main predictors of EAW proficiency among high school students. Conclusion: Zhangzhou high school students' CTDs were overall positive, and students' EAW performance correlated significantly with the overall CTD and its four subdispositions of cognitive maturity, truth-seeking, analyticity, and justice. These four subdispositions showed a significantly predictive validity on EAW performance as well.


Assuntos
Resolução de Problemas , Pensamento , Humanos , Aprendizagem , Estudantes , Redação
3.
Adv Mater ; 35(26): e2301127, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37119501

RESUMO

The electrochemical reduction of carbon dioxide into multi-carbon products (C2+ ) using renewably generated electricity provides a promising pathway for energy and environmental sustainability. Various oxide-derived copper (OD-Cu) catalysts have been showcased, but still require high overpotential to drive C2+ production owing to sluggish carbon-carbon bond formation and low CO intermediate (*CO) coverage. Here, the dilemma is circumvented by elaborately devising the OD-Cu morphology. First, computational studies propose a hollow and hierarchical OD-Cu microstructure that can generate a core-shell microenvironment to inhibit CO evolution and accelerate *CO dimerization via intermediate confinement and electric field enhancement, thereby boosting C2+ generation. Experimentally, the designed nanoarchitectures are synthesized through a heteroseed-induced approach followed by electrochemical activation. In situ spectroscopic studies further elaborate correlation between *CO dimerization and designed architectures. Remarkably, the hierarchical OD-Cu manifests morphology-dependent selectivity of CO2 reduction, giving a C2+ Faradaic efficiency of 75.6% at a considerably positive potential of -0.55 V versus reversible hydrogen electrode.

4.
Chem Commun (Camb) ; 59(19): 2799-2802, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36789697

RESUMO

Light, as a powerful energy source, has motivated the many endeavors of chemists in photochemical transformations. We were delighted to find that light has an inhibition effect on hydrogenation reactions. Exploring this previously unperceived effect will bring renewed understanding of interactions of light and matter. This work provides a breakthrough in ways to remotely control chemical reactions by light.

5.
Anal Chem ; 95(2): 1703-1709, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36583685

RESUMO

Disclosing the roles of reactive sites at catalytic interfaces is of paramount importance for understanding the reaction mechanism. However, due to the difficulties in the detection of reaction intermediates in the complex heterophase reaction system, disentangling the highly convolved roles of different surface atoms remains challenging. Herein, we used CoOx as a model catalyst to study the synergy of CoTd2+ and CoOh3+ active sites in the electrocatalytic oxygen evolution reaction (OER). The formation and evolution of reaction intermediates on the catalyst surface during the OER process were investigated by in situ surface-enhanced Raman spectroscopy (SERS). According to the SERS results in ion-substitution experiments, CoOh3+ is the catalytic site for the conversion of OH- to O-O- intermediate species (1140-1180 cm-1). CoOOH (503 cm-1) and CoO2 (560 cm-1) active centers generated during the OER, at the original CoTd2+ sites of CoOx, eventually serve as the O2 release sites (conversion of O-O- intermediate to O2). The mechanism was further confirmed on Co2+-Co3+ layered double hydroxides (LDHs), where an optimal ratio of 1:1.2 (Co2+/Co3+) is required to balance O-O- generation and O2 release. This work highlights the synergistic role of metal atoms at different valence statuses in water oxidation and sheds light on surface component engineering for the rational design of high-performance heterogeneous catalysts.

6.
Chem Sci ; 13(40): 11792-11797, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36320924

RESUMO

Colloidal superstructures comprising hetero-building blocks often show unanticipated physical and chemical properties. Here, we present a universal assembly methodology to prepare hetero-superstructures. This straightforward methodology allows the assembly of building block materials varying from inorganic nanoparticles to living cells to form superstructures. No molecular linker is required to bind the building blocks together and thus the products do not contain any unwanted adscititious material. The Fourier transform infrared spectra, high resolution transmission electron microscopic images and nanoparticle adhesion force measurement results reveal that the key to self-organization is stripping surface ligands by adding non-polar solvents or neutralizing surface charge by adding salts, which allow us to tune the balance between van der Waals attraction and electrostatic repulsion in the colloid so as to trigger the assembling process. As a proof-of-concept, the superior photocatalytic activity and single-particle surface-enhanced Raman scattering of the corresponding superstructures are demonstrated. Our methodology greatly extends the scope of building blocks for superstructure assembly and enables scalable construction of colloidal multifunctional materials.

7.
Biomed Res Int ; 2022: 8213895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093407

RESUMO

Homocysteine is an amino acid present in plasma, which is an important intermediate product in the metabolism of methionine and cysteine. Acute cerebral infarction (CI) is called acute CI of stroke. It is one of the most common diseases in neurology and has a serious impact, affecting people's lives. This article is aimed at studying the effect of data mining algorithms based on medical big data and the improved apriori algorithm on the analysis of the correlation between collateral compensation and homocysteine levels in patients with acute CI. This article proposes that there are many factors in patients with acute CI, among which are collateral compensation and homocysteine levels that are not easily determined. From the data in the tables in the experiment of this article, it can be seen that the collateral circulation of patients with acute CI is 8%, and the collateral circulation of patients without acute CI is 35%. The results indicate that both collateral compensation and homocysteine levels affect patients with acute CI. The higher the homocysteine level, the greater the probability of acute CI, and the better the state of collateral circulation, the less likely it is to suffer from acute CI.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Doença Aguda , Big Data , Infarto Cerebral/tratamento farmacológico , Homocisteína , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica
8.
Life (Basel) ; 12(8)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36013415

RESUMO

NAC transcription factors play an important regulatory role in tomato fruit ripening. We chose a novel perspective to explore the traces left by two paleopolyploidizations in the NAC family using a bioinformatics approach. We found that 85 (S. lycopersicum) and 88 (S. pennellii) members of the NAC family were present in two tomatoes, and most of them were amplified from two paleohexaploidizations. We differentiated NAC family members from the different paleohexaploidizations and found that the SWGT-derived NAC genes had more rearrangement events, so it was different from the DWGT-derived NAC genes in terms of physicochemical properties, phylogeny, and gene location. The results of selection pressure show that DWGT-derived NAC genes tended to be positively selected in S. lycopersicum and negatively selected in S. pennellii. A comprehensive analysis of paleopolyploidization and expression reveals that DWGT-derived NAC genes tend to promote fruit ripening, and are expressed at the early and middle stages, whereas SWGT-derived NAC genes tend to terminate fruit growth and are expressed at the late stages of fruit ripening. This study obtained NAC genes from different sources that can be used as materials for tomato fruit development, and the method in the study can be extended to the study of other plants.

9.
Front Oncol ; 12: 916251, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35880167

RESUMO

Background: Increasing evidence indicates that immune cell infiltration (ICI) affects the prognosis of multiple cancers. This study aims to explore the immunotypes and ICI-related biomarkers in ovarian cancer. Methods: The ICI levels were quantified with the CIBERSORT and ESTIMATE algorithms. The unsupervised consensus clustering method determined immunotypes based on the ICI profiles. Characteristic genes were identified with the Boruta algorithm. Then, the ICI score, a novel prognostic marker, was generated with the principal component analysis of the characteristic genes. The relationships between the ICI scores and clinical features were revealed. Further, an ICI signature was integrated after the univariate Cox, lasso, and stepwise regression analyses. The accuracy and robustness of the model were tested by three independent cohorts. The roles of the model in the immunophenoscores (IPS), tumor immune dysfunction and exclusion (TIDE) scores, and immunotherapy responses were also explored. Finally, risk genes (GBP1P1, TGFBI, PLA2G2D) and immune cell marker genes (CD11B, NOS2, CD206, CD8A) were tested by qRT-PCR in clinical tissues. Results: Three immunotypes were identified, and ICI scores were generated based on the 75 characteristic genes. CD8 TCR pathways, chemokine-related pathways, and lymphocyte activation were critical to immunophenotyping. Higher ICI scores contributed to better prognoses. An independent prognostic factor, a three-gene signature, was integrated to calculate patients' risk scores. Higher TIDE scores, lower ICI scores, lower IPS, lower immunotherapy responses, and worse prognoses were revealed in high-risk patients. Macrophage polarization and CD8 T cell infiltration were indicated to play potentially important roles in the development of ovarian cancer in the clinical validation cohort. Conclusions: Our study characterized the immunotyping landscape and provided novel immune infiltration-related prognostic markers in ovarian cancer.

10.
J Phys Chem Lett ; 13(24): 5495-5500, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35695751

RESUMO

Due to the challenge in measuring hot electron energy under reaction conditions, very few studies focus on experimental determination of hot carrier energy. Here, we adjust the energy state of free electrons in Au nanoparticles to quantify the hot electron energy in plasmonic photocatalysis. Reactant molecules with different reduction potentials such as 4-nitrothiophenol (4-NTP), 4-iodothiophenol (4-ITP), etc. are chosen as molecular probes to investigate the reducing ability of hot electrons. By comparing the voltage required to achieve the same conversion of photo- and electro-reaction pathways, we calibrate the maximum energy efficiency of hot electrons in 4-NTP reduction to be 0.32 eV, which is much lower than the excitation photon energy of 1.96 eV. Our work provides insight into the energy distribution of hot electrons and will be helpful for rational design of highly efficient plasmon-mediated chemical reactions.

11.
Chemistry ; 28(36): e202200138, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35441499

RESUMO

Water-splitting has emerged as a promising alternative strategy to produce clean hydrogen fuel. However, current electrocatalytic water splitting suffers from sluggish kinetics, thus developing efficient electrocatalysts is crucial. Identifying reaction centers discloses the reaction mechanism and will undoubtedly facilitate the design and optimization of efficient water splitting electrocatalysts. This review summarizes several advances involving the identification of the actual active sites and intermediates capture on the catalytic surface. The morphology and valence states change on 2D materials are chose to illustrate how structural evolution affect catalytic activity. Specifically, in situ/ex situ electron microscopy techniques that used for the characterization of catalytic sites, and spectroscopy techniques that used to detect active intermediates at the molecular level are highlighted. In addition, several perspectives, such as the development of new in situ techniques and electrokinetic analysis methods, are emphasized to shed light on future research.


Assuntos
Hidrogênio , Água , Catálise , Domínio Catalítico , Elétrons
12.
J Am Chem Soc ; 144(11): 5003-5009, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35286081

RESUMO

The central dilemma in label-free in situ surface-enhanced Raman scattering (SERS) for monitoring of heterogeneously catalyzed reactions is the need of plasmonically active nanostructures for signal enhancement. Here, we show that the assembly of catalytically active transition-metal nanoparticles into dimers boosts their intrinsically insufficient plasmonic activity at the monomer level by several orders of magnitude, thereby enabling the in situ SERS monitoring of various important heterogeneously catalyzed reactions at the single-dimer level. Specifically, we demonstrate that Pd nanocubes (NCs), which alone are not sufficiently plasmonically active as monomers, can act as a monometallic yet bifunctional platform with both catalytic and satisfactory plasmonic activity via controlled assembly into single dimers with an ∼1 nm gap. Computer simulations reveal that the highest enhancement factors (EFs) occur at the corners of the gap, which has important implications for the SERS-based detection of catalytic conversions: it is sufficient for molecules to come in contact with the "hot spot corners", and it is not required that they diffuse deeply into the gap. For the widely employed Pd-catalyzed Suzuki-Miyaura cross-coupling reaction, we demonstrate that such Pd NC dimers can be employed for in situ kinetic SERS monitoring, using a whole series of aryl halides as educts. Our generic approach based on the controlled assembly into dimers can easily be extended to other transition-metal nanostructures.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Catálise , Ouro/química , Nanopartículas Metálicas/química , Paládio , Polímeros
13.
World J Clin Cases ; 10(5): 1527-1535, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35211590

RESUMO

BACKGROUND: Osteoporosis is a systemic bone disease characterized by decreased bone mass, impaired bone mass, and reduced bone strength that leads to increased bone fragility and fracture. Type 2 diabetes mellitus (T2DM) complicated with osteoporosis is a common systemic metabolic bone disease, and reduced bone mass and bone strength are considered the main clinical features; however, the pathogenesis of this disease has not been fully clarified. Its occurrence is considered related to sex, age, and genetic factors. There are many risk factors for diabetes complicated with osteoporosis. Therefore, exploring these risk factors will help prevent it. AIM: To investigate the relationships among serum glucagon-like peptide-1 (GLP-1) levels, matrix Gla protein (MGP) levels, and diabetes with osteoporosis. METHODS: Sixty patients with T2DM complicated with osteoporosis confirmed by the endocrinology department of our hospital were selected as the case group. Sixty T2DM patients with bone loss were selected as the control group. Sixty healthy participants were selected as the healthy group. The general data, bone mineral density index, and bone metabolic markers of the three groups were compared. The relationships among GLP-1 levels, MGP levels, and the bone mineral density index of the case group were analyzed using linear correlation analysis and a logistic regression model. RESULTS: Differences in sex, smoking, and drinking among the case group, control group, and healthy group were not statistically significant (P > 0.05). The mean age of the case group was older than those of the control and healthy groups (P < 0.05). The body mass index, fasting plasma glucose level, HbA1c level, hypertension rate, and coronary heart disease rate of the case and control groups were higher than those of the healthy group (P < 0.05). The serum GLP-1 and MGP levels of the case group were lower than those of the control and healthy groups; these differences were statistically significant (P < 0.05). The serum GLP-1 and MGP levels of the control group were lower than those of the healthy group; these differences were statistically significant (P < 0.05). The serum GLP-1 and MGP levels of the case group were significantly positively correlated with the bone mineral density values of the hip and lumbar spine (P < 0.05). The results of the logistic regression model showed that age and duration of diabetes were independent risk factors for osteoporosis in diabetic patients (P < 0.05) and that increased GLP-1 and MGP values were protective factors against osteoporosis in diabetic patients (P < 0.05). CONCLUSION: Serum GLP-1 and MGP levels of diabetic patients with osteoporosis were significantly decreased and positively correlated with bone mineral density and were independent risk factors for osteoporosis in diabetic patients.

14.
Acta Trop ; 226: 106224, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34757041

RESUMO

BACKGROUND: Snails that host the parasitic worm Schistosoma were once controlled or eliminated in Wuhan, China. However, safety measures associated with the outbreak of novel coronavirus disease 2019 (COVID-19) halted snail detection and extermination efforts. The impact of the COVID-19 pandemic on urban schistosomiasis transmission remains unclear. This study aimed to investigate snail density and the associated risk of a schistosomiasis outbreak in Wuhan. METHODS: The density and infection status of snails were monitored by global positioning system satellites, and outbreak risk was calculated by adjusting the Kaiser model. SigmaPlot was used to create a three-dimensional risk matrix. RESULTS: The living snail frame occurrence rate was 1.48%, and the average living snail density was 0.054/0.11 m2 in 2020, indicating an increase relative to the respective 2019 values (0.019/0.11 m2). No infectious snails were observed in the survey area. The possibility, harmfulness, and uncontrollability indicator values were 0.842, 0.870, and 0.866, respectively. The areas at greatest risk were the northern bank of Tianxingzhou and the Tianxingzhou and Hongshan districts overall. The existing snail sites in the northern bank of Tianxingzhou exhibited the highest risk scores, followed by those in Pak Sha Chau, with the highest risk score found in Yangsiji Village. The events likely to occur in Hongshan District were also likely to have high severity. CONCLUSIONS: During the COVID-19 outbreak, the risk of schistosomiasis increased due to snail colonies returning to their sites of origin in Wuhan, suggesting a need for strengthened infection control and prevention measures.


Assuntos
COVID-19 , Animais , China/epidemiologia , Controle de Doenças Transmissíveis , Humanos , Pandemias , SARS-CoV-2 , Schistosoma
15.
Angew Chem Int Ed Engl ; 60(36): 19774-19778, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34184371

RESUMO

NiFe-based electrocatalysts have attracted great interests due to the low price and high activity in oxygen evolution reaction (OER). However, the complex reaction mechanism of NiFe-catalyzed OER has not been fully explored yet. Detection of intermediate species can bridge the gap between OER performances and catalyst component/structure properties. Here, we performed label-free surface-enhanced Raman spectroscopic (SERS) monitoring of interfacial OER process on Ni3 FeOx nanoparticles (NPs) in alkaline medium. By using bifunctional Au@Ni3 FeOx core-satellite superstructures as Raman signal enhancer, we found direct spectroscopic evidence of intermediate O-O- species. According to the SERS results, Fe atoms are the catalytic sites for the initial OH- to O-O- oxidation. The O-O- species adsorbed across neighboring Fe and Ni sites experiences further oxidation caused by electron transfer to NiIII and eventually forms O2 product.

16.
Medicine (Baltimore) ; 99(49): e23202, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285694

RESUMO

BACKGROUND: Rectovaginal fistula (RVF) is a pathologic channel between the anterior wall of the rectum and the posterior wall of the vagina, is rare, and the majority is of traumatic origin. The most common causes are obstetric trauma, local infection, rectal surgery or caused by chronic inflammatory bowel disease. Once the disease will seriously affect the patient's quality of life, and generally not self-healing, most require surgical intervention. At present, diverting stoma is mainly used in patients with severe RVF or complicated RVF or patients with Crohn disease. Due to the lack of large sample, linical studies, its clinical effectiveness is still controversial. The purpose of this systematic review is to evaluate the efficacy of diverting stoma in the treatment of diverting stoma. METHODS: EMBASE, PubMed, the Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Biomedical Literature Database (CBM), and Chinese VIP Information will be searched systematically by 2 reviewers from the inception until October 2020. The original study that randomized controlled trials (RCTs), clinical controlled trials (CCTs), nonrandomized control trials (NCTs), and retrospective trials (RTs) of diverting stoma for RVF will be selected. In addition, similar searches will be conducted for the reference lists, researches in progress, and the citation lists of identified publications. Study selection, data extraction, and assessment of the quality will be performed independently by 2 reviewers who have been trained prior to data extraction. A meta-analysis will be conduct if the quantity and quality of the original studies included are satisfactory; otherwise, a descriptive analysis will be conducted. Review Manager 5.4 software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark) will be using for data synthesis and assessment the risk of bias according by Cochrane Handbook. RESULT: This study will provide a comprehensive review of current evidence for the treatment of diverting stoma on RVF. CONCLUSION: The conclusion of this study will provide a judging basis that whether the treatment of RVF with diverting stoma is effective. INPLASY REGISTRATION NUMBER: INPLASY2020090070.


Assuntos
Fístula Retovaginal/cirurgia , Estomas Cirúrgicos , Feminino , Humanos , Metanálise como Assunto , Revisões Sistemáticas como Assunto
17.
Small ; 16(47): e2001529, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33140581

RESUMO

Selective oxidation of alcohols to aldehydes under mild conditions is important for the synthesis of high-value-added organic intermediates but still very challenging. For most of the thermal and photocatalytic systems, noble metal catalysts or harsh reaction conditions are required. Herein, the synthesis and use of Ag2 S-CdS p-n nanojunctions as an efficient photocatalyst for selective oxidation of a series of aromatic alcohols to their corresponding aldehydes is reported. High quantum efficiencies (59.6% and 36.9% under 380 and 420 nm, respectively) are achieved in air atmosphere at room temperature. Photoluminescence and photo-electrochemical tests show that the excellent performance is mainly due to the p-n junction-enhanced charge separation and transfer for the activation of both O2 (in air) and substrates. This study demonstrates the potential of p-n junction in photocatalytic synthesis under mild conditions.

18.
Angew Chem Int Ed Engl ; 59(41): 18003-18009, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32602629

RESUMO

This work reports on an assembling-calcining method for preparing gold-metal oxide core-satellite nanostructures, which enable surface-enhanced Raman spectroscopic detection of chemical reactions on metal oxide nanoparticles. By using the nanostructure, we study the photooxidation of Si-H catalyzed by CuO nanoparticles. As evidenced by the in situ spectroscopic results, oxygen vacancies of CuO are found to be very active sites for oxygen activation, and hydroxide radicals (*OH) adsorbed at the catalytic sites are likely to be the reactive intermediates that trigger the conversion from silanes into the corresponding silanols. According to our finding, oxygen vacancy-rich CuO catalysts are confirmed to be of both high activity and selectivity in photooxidation of various silanes.

19.
Angew Chem Int Ed Engl ; 58(27): 9049-9053, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31025515

RESUMO

Bifunctional Au@Ni core-satellite nanostructures synthesized by a one-step assembly method were employed for in situ surface-enhanced Raman spectroscopic (SERS) monitoring of Ni-catalyzed C-C bond-forming reactions. Surprisingly, the reaction that was thought to be an Ullmann-type self-coupling reaction, was found to be a cross-coupling reaction proceeding by photoinduced aromatic C-H bond arylation. In situ SERS monitoring enabled the discovery, and a series of biphenyl compounds were synthesized photocatalytically, and at room temperature, using cheap Ni nanoparticle catalysts.

20.
Mater Sci Eng C Mater Biol Appl ; 95: 256-263, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30573248

RESUMO

Graphene-based nanomaterials show great potential in photo-chemotherapy, but their photo-thermal effect is not very satisfactory. Herein, we presented a facile and low-cost strategy to grow Au clusters on the reduced graphene oxide (rGO) sheets aiming to improve photothermal effect. Au clusters with low-concentration was directly conjugated on the surface of rGO by electrostatic forces. To improve its biocompatibility, 3­(3­phenylureido) propanoic acid (PPA)-PEG (PPEG) had been introduced as biodegradable backbone to form rGO/Au/PPEG nanohybrids via π-π accumulation. The obtained rGO-based nanohybrids showed excellent biocompatibility, stability, low cytotoxicity, and enhanced photo-thermal conversion efficiency. To verify the synergistic photo-chemotherapy, doxorubicin (DOX) as a drug model had been loaded in rGO/Au/PPEG nanohybrids. The results indicated that rGO/Au/PPEG/DOX exhibited synergistic therapeutic efficacy compared with single chemotherapy or photothermal therapy, endowing this designed rGO-based nanohybrids with great potential for cancer treatments.


Assuntos
Ouro/química , Grafite/química , Fototerapia/métodos , Doxorrubicina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
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