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1.
Analyst ; 149(2): 304-349, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38051130

RESUMO

With the rapid development of fluorescent nanoparticles (FNPs), such as CDs, QDs, and MOFs, the construction of FNP-based probes has played a key role in improving chemical sensors. Ratiometric fluorescent probes exhibit distinct advantages, such as resistance to environmental interference and achieving visualization. Thus, FNP-based dual-emission ratiometric fluorescent probes (DRFPs) have rapidly developed in the field of metal ion and small molecule detection in the past few years. In this review, firstly we introduce the fluorescence sensing mechanisms; then, we focus on the strategies for the fabrication of DRFPs, including hybrid FNPs, single FNPs with intrinsic dual emission and target-induced new emission, and DRFPs based on auxiliary nanoparticles. In the section on hybrid FNPs, methods to assemble two types of FNPs, such as chemical bonding, electrostatic interaction, core satellite or core-shell structures, coordination, and encapsulation, are introduced. In the section on single FNPs with intrinsic dual emission, methods for the design of dual-emission CDs, QDs, and MOFs are discussed. Regarding target-induced new emission, sensitization, coordination, hydrogen bonding, and chemical reaction induced new emissions are discussed. Furthermore, in the section on DRFPs based on auxiliary nanoparticles, auxiliary nanomaterials with the inner filter effect and enzyme mimicking activity are discussed. Finally, the existing challenges and an outlook on the future of DRFP are presented. We sincerely hope that this review will contribute to the quick understanding and exploration of DRFPs by researchers.

2.
Infect Drug Resist ; 15: 6115-6128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277249

RESUMO

Background: Metagenomic next-generation sequencing (mNGS) has been widely studied, due to its ability of detecting all the microbial genetic information unbiasedly in a sample at one time and not relying on traditional culture. However, the application of mNGS in the diagnosis of clinical pathogens remains challenging. Methods: From December 2019 to March 2021, 134 specimens including Broncho alveolar lavage fluid (BAFL), blood, sputum, cerebrospinal fluid (CSF), bile, pleural fluid, pus, were continuously collected in The First Hospital of Qinhuangdao, and their retrospective diagnoses were classified into infectious disease (128, 95.5%) and noninfectious disease (6, 4.5%). The pathogen-detection performance of mNGS was compared with conventional microbiological tests (CMT) and culture method. In addition, the antibiotic resistance genes (ARGs) and evolutionary relationship of common drug-resistant A. baumannii were also analyzed. Results: Compared with CMT and culture methods, mNGS showed higher sensitivity in pathogen detection (74.2% vs 57.8%; P < 0.001 and 66.3% vs 31.7%; P < 0.001, respectively). Importantly, for cases that mNGS-positive only, 18 (35%) cases result in diagnosis modification, and 7 (23%) cases confirmed the clinical diagnosis. In 17 cases that A. baumannii were both detected in mNGS and culture, ade genes were the most frequently detected ARGs (from 13 cases), followed by sul2 and APH(3")-Ib (both from 12 cases). High consistency was observed among these ARGs and the related phenotype (100% for ade genes, 91.6% for sul2 and APH(3")-Ib). A. baumannii strains were classified into three groups, and most were well-clustered. It suggested those strains may be the epidemic strains. Conclusion: In our study, mNGS had a higher sensitivity than CMT and culture method. And the result of ARGs frequency and cluster analysis of A. baumannii was of great significance to the anti-infective therapy.

3.
ACS Omega ; 6(25): 16565-16572, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34235328

RESUMO

Manganese dioxide (MnO2) nanosheet-based fluorescence sensors often use oxidase-like activity or wide absorption spectrum for detection of antioxidants. In those strategies, MnO2 nanosheets were reduced to Mn2+ by antioxidants. However, few strategies emphasize the role of Mn2+ obtained from MnO2 reduction in the design of the fluorescence sensor. Herein, we expanded the application of a MnO2 nanosheet-based fluorescence sensor by involving Mn2+ in the detection process using ascorbic acid (AA) as a model target. In this strategy, carbon dots (CDs), MnO2 nanosheets, and tetraphenylporphyrin tetrasulfonic acid (TPPS) comprise a ternary system for ratiometric fluorescence detection of AA. Initially, CDs were quenched by MnO2 nanosheets based on the inner filter effect, while TPPS maintained its fluorescence intensity. After the addition of AA, MnO2 nanosheets were reduced to Mn2+ so that the fluorescence intensity of CDs was recovered and TTPS was quenched by coordination with Mn2+. Overall, AA triggered an emission intensity increase at 440 nm for CDs and a decrease at 640 nm for TPPS. The ratio intensity of CDs to TPPS (F 440/F 640) showed a good linear relationship from 0.5 to 40 µM, with a low detection limit of 0.13 µM for AA detection. By means of the alkaline phosphatase (ALP)-triggered generation of AA, this strategy can be applied for the detection of ALP in the range of 0.1-100 mU/mL, with a detection limit of 0.04 mU/mL. Furthermore, this sensor was applied to detect AA and ALP in real, complex samples with ideal recovery. This novel platform extended the application of MnO2 nanosheet-based fluorescence sensors.

4.
Mediators Inflamm ; 2021: 7372893, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33551679

RESUMO

BACKGROUND: Our previous research showed the antioxidant activity of anthocyanins extracted from Aronia melanocarpa of black chokeberry in vitro. Ischemia acute kidney injury is a significant risk in developing progressive and deterioration of renal function leading to clinic chronic kidney disease. There were many attempts to protect the kidney against this progression of renal damage. Current study was designed to examine the effect of pretreatment with three anthocyanins named cyanidin-3-arabinoside, cyanidin-3-glucodise, and cyaniding-3-galactoside against acute ischemia-reperfusion injury in mouse kidney. METHODS: Acute renal injury model was initiated by 30 min clamping bilateral renal pedicle and followed by 24-hour reperfusion in C57Bl/6J mice. Four groups of mice were orally pretreated in 50 mg/g/12 h for two weeks with cyanidin-3-arabinoside, cyanidin-3-glucodise, and cyaniding-3-galactoside and anthocyanins (three-cyanidin mixture), respectively, sham-control group and the renal injury-untreated groups only with saline. RESULTS: The model resulted in renal dysfunction with high serum creatinine, blood urea nitrogen, and changes in proinflammatory cytokines (TNF-ɑ, IL-1ß, IL-6, and MCP-1), renal oxidative stress (SOD, GSH, and CAT), lipid peroxidation (TBARS and MDA), and apoptosis (caspase-9). Pretreatment of two weeks resulted in different extent amelioration of renal dysfunction and tubular damage and suppression of proinflammatory cytokines, oxidative stress, lipid peroxidation, and apoptosis, thus suggesting that cyanidins are potentially effective in acute renal ischemia by the decrease of inflammation, oxidative stress, and lipid peroxidation, as well as apoptosis. CONCLUSION: the current study provided the first attempt to investigate the role of anthocyanins purified from Aronia melanocarpa berry in amelioration of acute renal failure via antioxidant and cytoprotective effects.


Assuntos
Antocianinas/metabolismo , Falência Renal Crônica/metabolismo , Rim/efeitos dos fármacos , Photinia/metabolismo , Traumatismo por Reperfusão , Animais , Antocianinas/química , Antioxidantes/química , Apoptose , Arabinonucleosídeos/química , Peso Corporal , Caspase 9/metabolismo , Frutas , Galactosídeos/química , Inflamação , Rim/metabolismo , Peroxidação de Lipídeos , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Reperfusão , Risco
5.
Analyst ; 145(7): 2661-2668, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32104830

RESUMO

A simple core shell structured fluorescent sensor was constructed to realize simultaneous detection of hexavalent and trivalent chromium ions. Briefly, blue-carbon dots (b-CDs) were embedded into a silica sphere, then a Cr(iii) imprinted silica layer doped with red-CDs (r-CDs) was coated onto the b-CDs@SiO2. Cr(vi) can selectively quench b-CDs based on the inner filter effect and Cr(iii) can selectively quench r-CDs based on electron transfer with the aid of the ion imprinting technique. In this strategy, it was not necessary to reduce Cr(vi) to Cr(iii) or oxidize Cr(iii) to Cr(vi), the chromium speciation of both can be detected simultaneously. When Cr(vi) was detected in the blue channel, the fluorescence intensity quenching effect was seen at 440 nm, and was linear from 0.01 to 10.0 µM, with a detection limit of 3.8 nM. For the detection of Cr(iii) in the red channel, the fluorescence intensity quenching effect was seen at 605 nm, and was linear from 0.1 to 15.0 µM, with a detection limit of 46 nM. This strategy enjoyed the advantages of simple construction, convenient detection, good selectivity and high sensitivity.

6.
ACS Omega ; 4(25): 21500-21508, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31867546

RESUMO

A method for green synthesis of sulfur, nitrogen co-doped photoluminescence carbon dots (S,N/CDs) originating from two natural biomass was proposed. By simple hydrothermal heating of bean pod and onion, blue emission CDs were prepared. Ag+ can effectively quench the as-prepared S,N/CDs. Under optimized conditions, the linear range of the established method for Ag+ detection was 0.1-25 µM, and the detection of limit based on 3S/N was 37 nM. More interestingly, the addition of Ag+ can induce an evident color change of S,N/CDs from yellow to brown under sunlight. The developed method was applied for detection of Ag+ in river water and tap water samples. Satisfied recoveries ranging from 96.0 to 102.0% with precision below 4.1% were obtained. S,N/CDs showed low toxicity toward 4T1 cells, which also can be extended to cellular imaging and intracellular Ag+ detection. The simple and green approach proposed here could meet the requirements for bioimaging and environmental monitoring.

7.
Analyst ; 144(21): 6283-6290, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588432

RESUMO

When molecularly imprinted fluorescent polymers (MIFPs) are prepared by the doping method (d-MIFPs), the fluorescent nanoparticles are quenched and passivated during the polymerization and elution process, and their detection sensitivity would be reduced. In this study, to overcome this drawback, MIFPs were synthesized by post-imprinting modification based on multilevel mesoporous structured silica. Briefly, multilevel mesoporous-structured BPA-imprinted polymers (MIPs) were prepared at first, and then, CdTe quantum dots were anchored onto the large pores of the MIPs to form p-MIFPs. Due to the well-maintained fluorescence intensity and low background, the sensitivity of the p-MIFPs was two orders of magnitude higher than that of the d-MIFPs. The F0/F- 1 of p-MIFPs was linear with BPA in the range of 0.005 to 4.0 µM with an LOD of 0.57 nM. Furthermore, post-imprinting modification was adopted to achieve ratiometric fluorescent MIPs (p-r-MIFPs) by simultaneously anchoring carbon dots and quantum dots onto the MIPs. The p-MIFPs and p-r-MIFPs were successfully applied to determine BPA in water samples with average recoveries ranging from 96.4% to 102.0% and an RSD below 4.1%. The results prove that post-imprinting modification is an effective method to construct MIFPs with conspicuous sensitivity, and multilevel mesoporous silica is an ideal matrix for the post-imprinting modification.

8.
ACS Sens ; 4(7): 1917-1924, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31273977

RESUMO

Blue and red dual channel dual emission carbon dots (DDCDs) were synthesized by a one-step hydrothermal method in water-formamide binary system using citric acid and ethylenediamine as precursors. Then, the as-prepared DDCDs were directly employed for preparation of ion imprinted fluorescence polymers without further separation. Since Cr3+ can only quench the fluorescence of blue CDs, while Pb2+ only quenches the fluorescence of red CDs, dual channel detection of Cr3+ and Pb2+ can be achieved simultaneously based on ion imprinted fluorescence polymers. Under optimized conditions, the quenching effect [(F0 - F)/F0] at 440 nm for the blue channel against the concentration of Cr3+ was linear from 0.1 to 6.0 µM, while that for the red channel at 580 nm against the concentration of Pb2+ was linear from 0.1 to 5.0 µM. The detection limits for Cr3+ and Pb2+ can reach 27 nM and 34 nM, respectively. Satisfied recoveries have also been obtained for detection of Cr3+ and Pb2+ in real water samples. The application of this dual channel detection method will greatly simplify the heavy metal ion detection process in complicated water environments.


Assuntos
Carbono/química , Cromo/análise , Corantes Fluorescentes/química , Chumbo/análise , Polímeros/química , Pontos Quânticos/química , Cromo/química , Cor , Fluorescência , Lagos/análise , Chumbo/química , Limite de Detecção , Rios/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise
9.
ACS Appl Mater Interfaces ; 11(23): 20649-20659, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117440

RESUMO

A polymer micelle-based drug delivery system has faced many challenges due to the lack of stability especially after being diluted in blood, resulting in a premature release. Herein, we developed camptothecin (CPT)-conjugated prodrug (CPTP) micelles in which CPT was grafted to the poly(ethylene glycol)-poly(glutamic acid) block copolymer via a disulfide bond linker for a redox-triggered drug release. Then, the cisplatin (CDDP)-crosslinked CPT-prodrug micelles (CPTP/CDDP) with a hybrid complex as a stable structure were successfully established via the CDDP (Pt)-carboxyl (COOH) chelate interaction. The resulting dual CPTP/CDDP had an average hydrodynamic radius of about 50 nm with a narrow distribution, which was conducive to the promotion of solid tumor accumulation. Importantly, CPT chemical bonding to the polymer backbone obviously stabilizes the CPT-prodrug micelles and prolongs their circulation time. Moreover, both CPT and CDDP are clinically used antitumor drugs; CDDP not only behaves as an ancillary anticarcinogen but also serves as a crosslinker to restrain the untimely burst release of CPT and to achieve synergistic antitumor efficacy. In addition, the CPTP/CDDP also exhibited a sustained reduction responsive release of CPT accompanied by the dissociation of the CDDP-COOH complex. This design ingeniously solved the contradiction between the stability and release of polymer micelle-based nanomedicines. Both in vitro and in vivo tests demonstrated an amazing antineoplastic efficacy compared with free drugs (CPT or CDDP) and just their physical mixing, indicating great promise for cancer treatment.


Assuntos
Antineoplásicos/química , Camptotecina/química , Cisplatino/química , Nanomedicina/métodos , Pró-Fármacos/química , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Camptotecina/administração & dosagem , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Polietilenoglicóis/química , Ácido Poliglutâmico/química
10.
Anal Chim Acta ; 1048: 178-185, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30598148

RESUMO

A simple and sensitive inner filter effect and charge transfer dual response ratiometric fluorescent probe (D-RFP) for sensing glucose was developed based on etching of silver nanoprisms (Ag NPRs). The D-RFP was proposed by hybridizing red emitting CdTe QDs and blue emitting CDs into core-shell structured silica nanoparticles. In this design, when mixed Ag NPRs with the D-RFP, QDs which embedded in silica nanoparticles can be quenched by Ag NPRs via inner filter effect. Ag NPRs can be effectively etched to silver ions by H2O2 which can bind with CDs and quench CDs by charge transfer. The etching of Ag NPRs leaded to the recovering the fluorescence of QDs and quenching the fluorescence of CDs. Under optimal condition, D-RFP can be exploited for H2O2 detection with detection limit of 0.28 µM and glucose sensing with detection limit of 0.64 µM. The developed approach was applied to monitor glucose levels in human serum samples with satisfactory results. Moreover, this method provided a new idea for designing D-RFP and can be extended to other detection systems based on silver nanoparticles (including Ag NPs, Ag NPRs, or Au@Ag nanorods) etching process.


Assuntos
Colorimetria/métodos , Corantes Fluorescentes/química , Glucose/análise , Peróxido de Hidrogênio/sangue , Pontos Quânticos/química , Prata/química , Compostos de Cádmio/química , Carbono/química , Cor , Diabetes Mellitus/sangue , Fluorescência , Corantes Fluorescentes/síntese química , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução , Dióxido de Silício/química , Telúrio/química
11.
Analyst ; 144(4): 1153-1158, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30534771

RESUMO

Based on the inner filter effect and charge transfer dual response mechanism, a dual response ratiometric fluorescent probe (D-RFP) with two reversible signal changes for sensing H2O2 and glucose was developed. The D-RFP was proposed by embedding glycine-derived carbon dots (CDs) (λem = 400 nm) into silica nanoparticles and covalently linking CdTe quantum dots (QDs) (λem = 600 nm) onto the surface of silica nanoparticles. When silver nanoparticles (Ag NPs) were mixed with D-RFP, the fluorescence intensity of CDs can be quenched by Ag NPs via the inner filter effect. With the addition of H2O2, Ag NPs were etched to silver ions, thus recovering the fluorescence of CDs. In the meantime, fluorescence of QDs was quenched by Ag+via charge transfer. Under optimal conditions, D-RFP displayed high sensitivity toward H2O2 with a detection limit of 0.28 µM. Based on the conversion of glucose into H2O2, D-RFP can also be exploited for glucose sensing with a detection limit of 0.59 µM. The approach developed can be applied to monitor glucose levels in human serum samples with satisfactory results, and the results of the heathy and diabetic patients can be distinguished by the naked eye. Moreover, this method provides a new idea for designing a high-sensitivity D-RFP.


Assuntos
Glicemia/análise , Colorimetria/métodos , Corantes Fluorescentes/química , Peróxido de Hidrogênio/análise , Nanopartículas Metálicas/química , Prata/química , Carbono/química , Humanos , Pontos Quânticos/química , Sensibilidade e Especificidade , Dióxido de Silício/química
12.
Mol Ther Oncolytics ; 15: 248-260, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31890869

RESUMO

miR-424-5p has been widely identified to function as an oncomiR in multiple human cancer types. However, the biological function of miR-424-5p in distant metastasis of thyroid cancer, as well as the underlying mechanism, remains not clarified yet. In the current study, miR-424-5p expression was elucidated in 10 paired fresh thyroid cancer tissues and the thyroid cancer dataset from The Cancer Genome Atlas (TCGA). Lung metastasis colonization models in vivo and functional assays in vitro were used to determine the role of miR-424-5p in thyroid cancer. Bioinformatics analysis, western blot, luciferase reporter, and immunofluorescence assays were applied to identify the potential targets and underlying mechanism involved in the functional role of miR-424-5p in lung metastasis of thyroid cancer. Here, we reported that miR-424-5p was upregulated in thyroid cancer, and overexpression of miR-424-5p significantly correlated with distant metastasis of thyroid cancer. Upregulating miR-424-5p promoted, whereas silencing miR-424-5p inhibited, anoikis resistance in vitro and lung metastasis in vivo. Mechanistic investigation further revealed that miR-424-5p promoted anoikis resistance and lung metastasis by inactivating Hippo signaling via simultaneously targeting WWC1, SAV1, and LAST2. Therefore, our results support the idea that miR-424-5p may serve as a potential therapeutic target in lung metastasis of thyroid cancer.

13.
J Agric Food Chem ; 65(44): 9807-9814, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29068213

RESUMO

In this work, we developed a simple and sensitive ratiometric fluorescent assay for sensing trinitrotoluene (TNT) based on the inner filter effect (IFE) between gold nanoparticles (AuNPs) and ratiometric fluorescent nanoparticles (RFNs), which was designed by hybridizing green emissive carbon dots (CDs) and red emissive quantum dots (QDs) into a silica sphere as a fluorophore pair. AuNPs in their dispersion state can be a powerful absorber to quench CDs, while the aggregated AuNPs can quench QDs in the IFE-based fluorescent assays as a result of complementary overlap between the absorption spectrum of AuNPs and emission spectrum of RFNs. As a result of the fact that TNT can induce the aggregation of AuNPs, with the addition of TNT, the fluorescent of QDs can be quenched, while the fluorescent of CDs would be recovered. Then, ratiometric fluorescent detection of TNT is feasible. The present IFE-based ratiometric fluorescent sensor can detect TNT ranging from 0.1 to 270 nM, with a detection limit of 0.029 nM. In addition, the developed method was successfully applied to investigate TNT in water and soil samples with satisfactory recoveries ranging from 95 to 103%, with precision below 4.5%. The simple sensing approach proposed here could improve the sensitivity of colorimetric analysis by changing the ultraviolet analysis to ratiometric fluorescent analysis and promote the development of a dual-mode detection system.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Espectrometria de Fluorescência/métodos , Trinitrotolueno/química , Fluorescência , Limite de Detecção , Pontos Quânticos/química
14.
J Chromatogr A ; 1501: 10-17, 2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28473199

RESUMO

Novel hollow mesoporous molecularly imprinted polymers (HM-MIPs) were proposed for highly selective and sensitive detection of estrogens in food samples. HM-MIPs were prepared by one-pot surface imprinting method using17ß-estradiol (E2) as template followed by chemical selective etching to remove solid silica core. Transmission electron microscopy coupled with N2 adsorption experiment confirmed the successful formation of hollow mesoporous structure. Binding adsorption experiment indicated that HM-MIPs have high binding capacity and fast mass transfer property, and class selective recognition of estrogens is possible by E2 imprinted HM-MIPs. HM-MIPs-SPE-HPLC was employed to enrich and detect E1, E2 and E3 in cucumber, milk powder and grass carp samples. Satisfactory recoveries in the range of 85.6%-101.2% and relative standard deviation lower than 4.3% were obtained. The limits of detection for these estrogens were in the range of 33-22ngL-1. Thus, HM-MIPs-SPE method proved to be an accuracy and practical platform for detection of estrogens in food samples.


Assuntos
Cucumis sativus/química , Estrogênios/isolamento & purificação , Leite/química , Polímeros/química , Extração em Fase Sólida/métodos , Adsorção , Animais , Carpas , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/química , Contaminação de Alimentos/análise , Microscopia Eletrônica de Transmissão , Impressão Molecular , Polímeros/síntese química , Porosidade , Sensibilidade e Especificidade , Extração em Fase Sólida/instrumentação
15.
Biosens Bioelectron ; 92: 147-153, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28213327

RESUMO

Construction of ratiometric fluorescent probe often involved in tedious multistep preparation or complicated coupling or chemical modification process. The emergence of dual emission fluorescent nanoparticles would simplify the construction process and avoids the tedious chemical coupling. Herein, we reported a facile strategy to prepare ratiometric fluorescence molecularly imprinted sensor based on dual emission nanoparticles (d-NPs) which comprised of carbon dots and gold nanoclusters for detection of Bisphenol A (BPA). D-NPs emission at 460nm and 580nm were first prepared by seed growth co-microwave method using gold nanoparticles as seeds and glucose as precursor for carbon dots. When they were applied to propose ratiometric fluorescence molecularly imprinted sensor, the preparation process was simplified, and the sensitivity of sensor was improved with detection limit of 29nM, and visualizing BPA was feasible based on the distinguish fluorescence color change. The feasibility of the developed method in real samples was successfully evaluated through the analysis of BPA in water samples with satisfactory recoveries of 95.9-98.9% and recoveries ranging from 92.6% to 98.6% in canned food samples. When detection BPA in positive feeding bottles, the results agree well with those obtained by accredited method. The developed method proposed in this work to prepare ratiometric fluorescence molecularly imprinted sensor based on dual emission nanoparticles proved to be a convenient, reliable and practical way to prepared high sensitive and selective fluorescence sensors.


Assuntos
Compostos Benzidrílicos/análise , Corantes Fluorescentes/química , Impressão Molecular/métodos , Nanopartículas/química , Fenóis/análise , Polímeros/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Técnicas Biossensoriais/métodos , Carbono/química , Água Potável/análise , Contaminação de Alimentos/análise , Embalagem de Alimentos , Ouro/química , Nanopartículas/ultraestrutura , Pontos Quânticos/química , Pontos Quânticos/ultraestrutura , Rios/química
16.
Tumour Biol ; 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27812930

RESUMO

MiR-375 has been recognized as an important tumor suppressor and is usually downregulated in cervical cancer. However, how it is downregulated in cervical cancer is not clear. By using cancerous and normal cervical tissues, we observed that miR-375 and Dicer are both downregulated and were positively correlated. Overexpression of miR-375 resulted in decreased viral E6 and increased Dicer expression in both Hela and SiHa cells. Previous studies suggest that E6 can induce an accelerated degradation of TAp63ß, while TAp63 can bind to and transactivate the Dicer promoter, exerting a direct regulation on transcription of Dicer. In this study, we found that miR-375 overexpression restored TAp63ß expression. TAp63ß overexpression significantly enhanced transcription and translation of Dicer, which further led to increased mature miR-375 levels. Therefore, we infer that there is an E6-TAp63ß-Dicer feedback loop involved in miR-375 dysregulation in cervical cancer. Besides, we observed that enforced TAp63ß expression significantly reduced the mesenchymal markers including N-cadherin, Vimentin, Snail, and Slug but increased the epithelial marker E-cadherin in both Hela and SiHa cells. The wound healing assay also confirmed that TAp63ß overexpression significantly suppressed cervical cancer cell migration potential. These results suggest that TAp63ß can inhibit epithelial-to-mesenchymal transition (EMT) of cervical cancer cells.

17.
J Agric Food Chem ; 64(24): 5110-6, 2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27257079

RESUMO

Novel magnetic hollow molecularly imprinted polymers (M-H-MIPs) were proposed for highly selective recognition and fast enrichment of triazines in food samples. M-H-MIPs were prepared on the basis of multi-step swelling polymerization, followed by in situ growth of magnetic Fe3O4 nanoparticles on the surface of hollow molecularly imprinted polymers (H-MIPs). Transmission electron microscopy and scanning electron microscopy confirmed the successful immobilization of Fe3O4 nanoparticles on the surface of H-MIPs. M-H-MIPs could be separated simply using an external magnet. The binding adsorption results indicated that M-H-MIPs displayed high binding capacity and fast mass transfer property and class selective property for triazines. Langmuir isotherm and pseudo-second-order kinetic models fitted the best adsorption models for M-H-MIPs. M-H-MIPs were used to analyze atrazine, simazine, propazine, and terbuthylazine in corn, wheat, and soybean samples. Satisfactory recoveries were in the range of 80.62-101.69%, and relative standard deviation was lower than 5.2%. Limits of detection from 0.16 to 0.39 µg L(-1) were obtained. When the method was applied to test positive samples that were contaminated with triazines, the results agree well with those obtained from an accredited method. Thus, the M-H-MIP-based dispersive solid-phase extraction method proved to be a convenient and practical platform for detection of triazines in food samples.


Assuntos
Contaminação de Alimentos/análise , Polímeros/química , Extração em Fase Sólida/instrumentação , Triazinas/isolamento & purificação , Adsorção , Magnetismo , Impressão Molecular , Nanopartículas/química , Polímeros/síntese química , Triazinas/química
18.
Biosens Bioelectron ; 85: 950-956, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27315521

RESUMO

A facile strategy was developed to prepare mesoporous structured molecularly imprinted polymers capped carbon dots (M-MIPs@CDs) fluorescence sensor for highly sensitive and selective determination of TNT. The strategy using amino-CDs directly as "functional monomer" for imprinting simplify the imprinting process and provide well recognition sites accessibility. The as-prepared M-MIPs@CDs sensor, using periodic mesoporous silica as imprinting matrix, and amino-CDs directly as "functional monomer", exhibited excellent selectivity and sensitivity toward TNT with detection limit of 17nM. The recycling process was sustainable for 10 times without obvious efficiency decrease. The feasibility of the developed method in real samples was successfully evaluated through the analysis of TNT in soil and water samples with satisfactory recoveries of 88.6-95.7%. The method proposed in this work was proved to be a convenient and practical way to prepare high sensitive and selective fluorescence MIPs@CDs sensors.


Assuntos
Carbono/química , Poluentes Ambientais/análise , Substâncias Explosivas/análise , Corantes Fluorescentes/química , Impressão Molecular , Polímeros/química , Trinitrotolueno/análise , Técnicas Biossensoriais/métodos , Monitoramento Ambiental/métodos , Limite de Detecção , Impressão Molecular/métodos , Pontos Quânticos/química , Pontos Quânticos/ultraestrutura , Dióxido de Silício/química , Solo/química , Espectrometria de Fluorescência/métodos , Água/análise
19.
Tumour Biol ; 37(2): 1683-91, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26311052

RESUMO

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a lncRNA playing oncogenic role in several cancers, including cervical cancer. However, its role in radiosensitivity of cervical cancer is not yet well understood. This study explored the role of MALAT1 in radiosensitivity of high-risk human papillomavirus (HR-HPV)-positive cervical cancer and whether there is a ceRNA mechanism which participated in its regulation over radiosensitivity. Based on tissue samples from 50 cervical cancer cases and 25 healthy controls, we found MALAT1 expression was significantly higher in radioresistant than in radiosensitive cancer cases. In addition, MALAT1 and miR-145 expression inversely changed in response to irradiation in HR-HPV+ cervical cancer cells. By using clonogenic assay and flow cytometry analysis of cell cycle distribution and apoptosis, we found CaSki and Hela cells with knockdown of MALAT1 had significantly lower colony formation, higher ratio of G2/M phase block and higher ratio of cell apoptosis. By performing RNA-binding protein immunoprecipitation (RIP) assay and RNA pull-down assay, we confirmed that miR-145 and MALAT1 were in the same Ago2 complex and there was a reciprocal repression between them. Then, we explored the function of MALAT1-miR-145 in radiosensitivity of cervical cancers cells and demonstrated that si-MALAT1 and miR-145 had some level of synergic effect in reducing cancer cell colony formation, cell cycle regulation, and inducing apoptosis. These findings provide an important clue about microRNA-lncRNA interaction in the mechanism of radioresistance of cervical cancer.


Assuntos
MicroRNAs/genética , RNA Longo não Codificante/genética , Tolerância a Radiação/genética , Neoplasias do Colo do Útero/genética , Adulto , Apoptose/genética , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Técnicas de Silenciamento de Genes , Humanos , Imunoprecipitação , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , Transfecção , Neoplasias do Colo do Útero/virologia
20.
Talanta ; 144: 303-11, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26452826

RESUMO

In the present work, mesoporous structured estrone (E1) imprinted Fe3O4@SiO2@mSiO2 (MM-MIPs) was prepared and applied as extraction sorbent for selective pre-concentration and specific recognition of E1, 17ß-estradiol (E2) and estriol (E3) from water samples. MM-MIPs present higher binding capacity, faster mass transfer and higher extraction efficiency for three estrogens than the non-porous structured Fe3O4@SiO2. Application of MM-MIPs to dispersive solid phase extraction of three estrogens from spiked tap, river and lake water samples at 0.5, 1.0, 10 µg L(-1) resulted in good recoveries ranging from 85% to 95% with relative standard deviation values lower than 6.0% in all cases. Limits of detection were in the range of 0.086-0.43 µg L(-1). The extraction method based on MM-MIPs proved to be a highly-effective enrichment method with enrichment factor about 1700, which is much higher than the value nearly 620 obtained by non-mesoporous Fe3O4@SiO2, during the process of simultaneous separation and sensitive determination of estrogens in complicated water samples. Furthermore, the mesoporous silica could be expanded to imprint other compounds.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/análise , Estrona/química , Óxido Ferroso-Férrico/química , Impressão Molecular , Dióxido de Silício/química , Água/química , Porosidade , Poluentes Químicos da Água/análise
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