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1.
Top Curr Chem (Cham) ; 377(5): 25, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529217

RESUMO

Metal-organic frameworks (MOFs) have gathered tremendous interest among researchers for their potential applications such as in storage and separation. While some progress has been made towards shaping of MOFs to realize industrial applications, the mechanical properties of MOFs remain more or less unexplored. Over the last decade, this area has witnessed a steady growth in terms of understanding the mechanical stability of MOFs and its consequence on their performance. In this review, the mechanical properties of the reported macroscopic shaped MOF structures (mainly granules, pellets, tablets, monoliths, and gels) are discussed. Conclusions are then drawn to determine which shapes and shaping techniques promise to meet industrial requirements on the basis of mechanical stability. Finally, future research directions are proposed to improve our understanding, and possibly enhance stability, by correlating the properties from microscopic single-crystalline level to the industrially relevant macroscopic polycrystalline scale.


Assuntos
Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
2.
Chem Pharm Bull (Tokyo) ; 67(8): 801-809, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366829

RESUMO

Granules prepared by a continuous twin screw granulator (TSG) were analyzed by X-ray micro-computed tomography (X-ray µCT) and the relationships between porosity of granules and granule properties were investigated. A model formulation containing ibuprofen, lactose monohydrate, microcrystalline cellulose, and hydroxypropyl cellulose was used. The porosity of granules was measured by X-ray µCT and mercury porosimetry. The data sets obtained by both methods showed linear correlation despite different values, which were attributed to the resolution of X-ray µCT and a low-signal-to-noise ratio of the original cross-sectional images. The porosity of granules measured by X-ray µCT decreased from 11-14 to 6-7% as liquid-to-solid ratio (L/S) increased, while the standard deviation (S.D.) of the porosity of individual granules decreased from 4-5 to 2%. L/S affected the porosity of granules. By contrast, the effect of screw speed was not significant. Pressure transmission, G, which indicates the liquid dispersion in wet kneaded masses, increased as the porosity of granules and the S.D. decreased. The cross-sectional images showed that granules were densified as L/S increased. Based on these results, the effect of L/S on the porosity of granules can be explained by liquid dispersion and densification of the wet granules. The porosity of granules measured by X-ray µCT showed good linear correlation with friability and drug dissolution rate (R2 = 0.9107 and 0.8834, respectively). This study revealed that the drug dissolution rate was regulated by a disintegration step in which the porosity of granules plays an important role.


Assuntos
Parafusos Ósseos , Tecnologia Farmacêutica , Microtomografia por Raio-X , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Raios X
3.
J Biomed Nanotechnol ; 15(10): 2100-2107, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31462374

RESUMO

In this paper, an enzyme-linked immunosorbent assay (ELISA) using gold nanoparticles/metal porphyrin porous compound (Au NPs@PAF-40-Fe) as a marker was developed. Quantitative detection of C-reactive protein (CRP) was achieved by UV-visible spectrophotometry under optimal conditions. The sensor has a good linear relationship in the range of 0.05-2000 ng/mL. The lower limit of detection was 0.017 ng/mL (S/N = 3), the linear correlation coefficient was 0.9921, and the average recovery was 100.74%. The ELISA has good selectivity and provides a sensitive way for detection of CRP.


Assuntos
Nanopartículas Metálicas , Proteína C-Reativa , Ensaio de Imunoadsorção Enzimática , Ouro , Porosidade , Porfirinas
4.
Analyst ; 144(17): 5261-5270, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31364612

RESUMO

In this work, an enrichment approach for the profiling of N-linked glycans was developed by utilizing a highly porous 3D graphene composite fabricated from graphene oxide nanosheets and a phenol-formaldehyde polymer via graphitization and KOH activation. In tailoring the large surface area (ca. 2213 m2 g-1) and 3D-layered mesoporous structure, the 3D graphene composite demonstrated not only high efficiency in glycan enrichment but also the size-exclusion effect against residual protein interference. For a standard protein ovalbumin digest, 26 N-linked glycans were identified with good repeatability, and the detection limit was as low as 0.25 ng µL-1 with the identification of 13 N-linked glycans (S/N > 10). When the mass ratio of the ovalbumin digest to the interfering proteins, i.e., bovine serum albumin and ovalbumin was 1 : 2000 : 2000, 18 N-linked glycans could still be detected with sufficient signal intensities. From a 60 nL minute complex human serum sample, up to 53 N-linked glycans with S/N > 10 were identified after the 3D graphene enrichment, while only 20 N-linked glycans were identified by the porous graphitized carbon material used for comparison. In addition, the application of the 3D graphene composite in profiling the up-regulated and down-regulated N-linked glycans from the real clinical serum samples of ovarian cancer patients confirmed the potential of the 3D graphene composite for analyzing minute and complicated biological samples.


Assuntos
Grafite/química , Nanoestruturas/química , Ovalbumina/química , Polissacarídeos/análise , Albumina Sérica/química , Feminino , Formaldeído/química , Humanos , Neoplasias Ovarianas/sangue , Oxirredução , Fenol/química , Fenóis/química , Polímeros/química , Polissacarídeos/isolamento & purificação , Porosidade , Soro
5.
Pharm Res ; 36(10): 150, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31428879

RESUMO

PURPOSE: The unconventional tabletability of the indomethacin polymorphs - α and γ - are investigated from a topological and mechanical perspective using powder Brillouin light scattering (p-BLS) to identify the specific structure-performance relationship in these materials. METHOD: Indomethacin (γ-form) was purchased and used to prepare the α polymorph. Powder X-ray diffraction was used to confirm phase identity, while p-BLS was used to obtain the mechanical properties. Energy frameworks were determined with Crystal Explorer to visualize the interaction topologies. Using a Carver press and a stress-strain analyzer, the tableting performance of each polymorph was determined. RESULTS: Polymorph-specific acoustic frequency distributions were observed with distinct, zero-porosity, aggregate elastic moduli determined. The p-BLS spectra for α-indomethacin display a population of low-velocity shear modes, indicating a direction of facilitated shear. This improves slip-mediated plasticity and tabletability. Our p-BLS spectra experimentally indicates that a low-energy slip system is available to α-indomethacin which supports ours and previous energy framework calculations. Despite a 2d-layered crystal motif favorable for shear deformation, the γ-form displays a higher shear modulus that is supported by our hydrogen-bonding analysis of γ-indomethacin. CONCLUSION: Our experimental, mechanical data is consistent with the predicted interaction topologies and these two inputs combined permit a comprehensive, molecular understanding of polymorph-specific tabletability.


Assuntos
Indometacina/química , Cristalização , Dimerização , Composição de Medicamentos , Ligações de Hidrogênio , Luz , Fenômenos Mecânicos , Porosidade , Pós , Espalhamento de Radiação , Comprimidos , Termodinâmica
6.
J Environ Manage ; 248: 109341, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31382192

RESUMO

In this work, we have assembled Bi2WO6 nanoparticles on the surface of honeycomb-like porous carbon skeleton (PCS) via a hydrothermal route to achieve a new type of PCS@Bi2WO6 hybrid composite photocatalysts. The PCS@Bi2WO6 hybrid structures are determined by SEM, TEM and XPS characterizations. UV-vis DRS investigation suggests an enhanced visible-light absorption of the PCS@Bi2WO6 composites. Transient photocurrent response, EIS and PL spectroscopy characterizations demonstrate that the composites exhibit an efficient separation of photoproduced electron/hole pairs. The photocatalytic performance of the composites were evaluated by using RhB as the model pollutant and simulated sunlight as the light source. It is revealed that the PCS@Bi2WO6 hybrid composites manifest much enhanced photocatalytic performance. The 5 wt%PCS@Bi2WO6 composite manifests the highest photocatalytic activity, which is ca. 2.1 times as large as that of bare Bi2WO6 nanoparticles. This can be mainly ascribed to two factors: (1) The photogenerated electron/hole pairs in Bi2WO6 are efficiently separated due to the electron transfer between Bi2WO6 and PCS; and (2) PCS induces enhanced visible-light absorption and the visible-light-excited electrons in PCS could also take part in the photocatalytic reactions.


Assuntos
Carbono , Nanopartículas , Catálise , Luz , Porosidade
7.
J Agric Food Chem ; 67(35): 9719-9726, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398015

RESUMO

Pickering high internal phase emulsions (HIPEs) are normally highly concentrated emulsions stabilized by colloidal particles with a minimum internal phase volume fraction of 0.74. They have received considerable attention in many fields, including pharmaceuticals, tissue engineering, foods, and personal care products. The aim of this perspective is to update the current knowledge on the field of protein-based Pickering HIPEs, emphasizing those aspects that need to be explored and clarified. Research progress in constructing HIPEs by protein-type colloid particles and promising research trends in basic research and potential applications were highlighted. Promising studies in this field include (1) clarifying bioavailability and evolution of activity of active ingredients in Pickering HIPEs by oral administration, (2) constructing a Pickering interfacial catalysis platform using protein colloidal particles, and (3) expanding the emerging applications of Pickering HIPEs in fields, such as partially hydrogenated oil replacers, probiotic encapsulation, and the template for porous materials.


Assuntos
Suplementos Nutricionais/análise , Emulsões/química , Proteínas/química , Coloides/química , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Nanopartículas/química , Tamanho da Partícula , Porosidade
8.
Int J Nanomedicine ; 14: 4975-4989, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371942

RESUMO

The porous surface of a polyetheretherketone (PK)-nanoporous lithium-doped magnesium silicate (NLS) blend (PKNLS) was fabricated on a PK surface by layer-by-layer pressuring, sintering, and salt-leaching. As controls, porous surfaces of a PK/lithium-doped magnesium silicate blend (PKLS) and PK were fabricated using the same method. The results revealed that porosity, water absorption, and protein absorption of the porous surface of PKNLS containing macropores and nanopores were obviously enhanced compared to PKLS and PK containing macropores without nanopores. In addition, PKNLS, with both macroporostiy and nanoporosity, displayed the highest ability of apatite mineralization in simulated body liquid, indicating excellent bioactivity. In vitro responses (including adhesion, proliferation, and differentiation) of MC3T3E1 cells to PKNLS were significantly enhanced compared to PKLS and PK. In vivo implantation results showed that new bone grew into the macroporous surface of PKNLS, and the amount of new bone for PKNLS was the highest. In short, PKNLS integration with PK significantly promoted cells/bone-tissue responses and exhibited excellent osteogenesis in vivo, which might have great potential for bone repair.


Assuntos
Osso e Ossos/fisiologia , Cetonas/farmacologia , Lítio/farmacologia , Silicatos de Magnésio/farmacologia , Nanoporos , Osteoblastos/citologia , Polietilenoglicóis/farmacologia , Adsorção , Fosfatase Alcalina/metabolismo , Animais , Apatitas/química , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Imagem Tridimensional , Masculino , Camundongos , Nanoporos/ultraestrutura , Osteoblastos/efeitos dos fármacos , Osteoblastos/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Coelhos , Água/química , Difração de Raios X
9.
Waste Manag ; 95: 504-512, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31351636

RESUMO

Paval, a solid waste stream from the aluminum industry, is used as a pore generation agent in geopolymers. Paval was mixed with coal combustion fly ash, as a geopolymeric precursor, and activated with alkaline solution with the aim of obtaining porous geopolymers to be used as noise barriers. Both geopolymeric and pore generation reactions happen simultaneously. Aluminum from Paval can react with water and OH¯ from the geopolymerization activating solution, producing hydrogen. The hydrogen gas released generates a highly porous material. The influence of the fly ash-paval proportion and the setting temperature on open porosity, compressive strength and noise-absorbing properties were evaluated. To better understand these influences, the setting time, volume expansion and mineral composition were also studied. The obtained results showed that a higher Paval content (fly ash-Paval ratio 50:50) and setting temperature (70 °C) produced a lower setting time and higher volume expansion, increasing the open porosity and improving acoustic properties, but reducing the compressive strength. The material manufactured under these conditions showed similar amorphous phase content to the non-porous geopolymers made without Paval. On the other hand, the obtained materials did not raise environmental concerns in a normalised leaching test.


Assuntos
Alumínio , Polímeros , Carvão Mineral , Cinza de Carvão , Porosidade
10.
Bioresour Technol ; 289: 121641, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31300306

RESUMO

Microbial anodes are the cornerstone of most electro-microbial processes. Designing 3-dimensional porous electrodes to increase the surface area of the electroactive biofilm they support is a key challenge in order to boost their performance. In this context, the critical review presented here aims to assess whether an optimal range of pore size may exist for the design of microbial anodes. Pore sizes of a few micrometres can enable microbial cells to penetrate but in conditions that do not favour efficient development of electroactive biofilms. Pores of a few tens of micrometres are subject to clogging. Sizes of a few hundreds of micrometres allow penetration of the biofilm inside the structure, but its development is limited by internal acidification. Consequently, pore sizes of a millimetre or so appear to be the most suitable. In addition, a simple theoretical approach is described to establish basis for porous microbial anode design.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes , Eletrodos , Porosidade
11.
Chem Commun (Camb) ; 55(62): 9104-9107, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31298232

RESUMO

We have developed a photoluminescent membrane for microRNA detection, consisting of chemically modified mesoporous silica nanoparticles (CaF2:Yb/Ho@MSNs) attached, via single stranded DNA probes, to flexible polyurethane fibres coated with graphene oxide (GO). By detecting the release of the luminescent nanoparticles resulting from complementary co-hybridization between target miRNA sequences and the DNA probe, accurate measurements of the miRNA concentration at high sensitivity levels can be obtained. The constructs therefore offer a route to rapid detection and the potential for early cancer diagnosis.


Assuntos
Técnicas Biossensoriais , Grafite/química , MicroRNAs/análise , Nanopartículas/química , Dióxido de Silício/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
12.
J Photochem Photobiol B ; 197: 111534, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279897

RESUMO

In the search for developing a biomedicine based nanomaterial for therapeutic applications, here we described a new benign development of Photo-triggered Gold nanodots capped mesoporous silica nanoparticles Au@MSNs loaded with capsaicin (Cap) for photothermal therapy of cancer cells. Electron microscopic techniques (SEM and TEM) studies depict the anisotropic shape of Cap-Au@MSNs with mean size ≈110 nm. The successful amine functionalization and covalent interaction of Au nanodots on the mesoporous silica surface were confirmed from the results of FTIR, XPS and UV-vis spectral analyses, which directly indicates the composition of synthesized mesoporous silica surface. Additionally, Dynamic Light Scattering (DLS) revealed that synthesized cap-AuMSNs were stable with highly negatively charged. Cap-AuMSNs exhibited extraordinary in vitro antitumor activity against the tested twp thyroid cancer cell lines (i.e., FTC-133 and B-CPAP). 3-(4, 5-Dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay determined that capsaicin and Cap-AuMSNs conferred strong cytotoxicity against the FTC-133 and B-CPAP cell lines. Further, evaluation of the mechanism showed that anticancer activity was achieved by inducing apoptosis in thyroid cancer cells. In addition, we found that such compounds exhibited promising antimetastatic activity and reduced the invasiveness of cancer cells. Hence, we suggesting that these Cap-Au@MSNs can be used as promising candidates for cancer therapy and deserve further investigation.


Assuntos
Capsaicina/química , Raios Infravermelhos , Nanopartículas/química , Nanoestruturas/química , Dióxido de Silício/química , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Ouro/química , Humanos , Microscopia Confocal , Fotoquimioterapia , Porosidade , Câncer Papilífero da Tireoide/tratamento farmacológico , Câncer Papilífero da Tireoide/patologia
13.
J Chromatogr A ; 1602: 178-187, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31301797

RESUMO

A magnetic porous covalent triazine-based organic polymer (M-PCTP) was synthesized by co-precipitation method. The M-PCTP combined both the properties of the PCTP and the magnetism of Fe3O4 nanoparticles, possessing highly porous structure and good magnetism. It was used as a magnetic solid phase extraction (MSPE) adsorbent to extract carbamate pesticides (propoxur, carbaryl, isoprocarb, fenobcarb and diethofencarb) from lemonade and grape juice samples prior to high performance liquid chromatography-mass spectrometric detection. Under the optimal conditions, a good linearity for the real samples was received in the range from 0.10-0.90 to 80.00 ng mL-1 with the correlation coefficients of 0.9882-0.9983. The method recoveries for the five carbamates were 86.3-108.0%. The limits of detection were 0.02-0.20 ng mL-1 for lemonade sample, and 0.04-0.30 ng mL-1 for grape juice sample. The M-PCTP also demonstrated good extraction capabilities for other different kinds of organic compounds including chlorophenols and polycyclic aromatic hydrocarbons.


Assuntos
Carbamatos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Espectrometria de Massas , Praguicidas/análise , Extração em Fase Sólida , Sucos de Frutas e Vegetais/análise , Magnetismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Polímeros/química , Porosidade
14.
Bone Joint J ; 101-B(7_Supple_C): 40-47, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31256643

RESUMO

AIMS: Our intention was to investigate if the highly porous biological fixation surfaces of a new 3D-printed total knee arthroplasty (TKA) achieved adequate fixation of the tibial and patellar components to the underlying bone. PATIENTS AND METHODS: A total of 29 patients undergoing primary TKA consented to participate in this prospective cohort study. All patients received a highly porous tibial baseplate and metal-backed patella. Patient-reported outcomes measures were recorded and implant migration was assessed using radiostereometric analysis. RESULTS: Patient function significantly improved by three months postoperatively (p < 0.001). Mean difference in maximum total point motion between 12 and 24 months was 0.021 mm (-0.265 to 0.572) for the tibial implant and 0.089 mm (-0.337 to 0.758) for the patellar implant. The rate of tibial and patellar migration was largest over the first six postoperative weeks, with no changes in mean tibia migration occurring after six months, and no changes in mean patellar migration occurring after six weeks. One patellar component showed a rapid rate of migration between 12 and 24 months. CONCLUSION: Biological fixation appears to occur reliably on the highly porous implant surface of the tibial baseplate and metal-backed patellar component. Rapid migration after 12 months was measured for one patellar component. Further investigation is required to assess the long-term stability of the 3D-printed components and to determine if the high-migrating components achieve fixation. Cite this article: Bone Joint J 2019;101-B(7 Supple C):40-47.


Assuntos
Artroplastia do Joelho/métodos , Cimentos para Ossos , Osteoartrite do Joelho/cirurgia , Patela/cirurgia , Impressão Tridimensional , Análise Radioestereométrica/métodos , Tíbia/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Patela/diagnóstico por imagem , Porosidade , Período Pós-Operatório , Estudos Prospectivos , Desenho de Prótese , Tíbia/diagnóstico por imagem , Adulto Jovem
15.
Bone Joint J ; 101-B(7_Supple_C): 55-60, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31256645

RESUMO

AIMS: Early implant migration measured with radiostereometric analysis (RSA) has been proposed as a useful predictor of long-term fixation of tibial components in total knee arthroplasty. Evaluation of actual long-term fixation is of interest for cemented components, as well as for cementless fixation, which may offer long-term advantages once osseointegration has occurred. The objective of this study was to compare the long-term migration with one- and two-year migration to evaluate the predictive ability of short-term migration data and to compare migration and inducible displacement between cemented and cementless (porous metal monoblock) components at least ten years postoperatively. PATIENTS AND METHODS: Patients who had participated in RSA migration studies with two-year follow-up were recruited to return for a long-term follow-up, at least ten years from surgery. Two cemented tibial designs from two manufacturers and one porous metal monoblock cementless tibial design were studied. At the long-term follow-up, patients had supine RSA examinations to determine migration and loaded examinations (single leg stance) to determine inducible displacement. In total, 79 patients (54 female) returned, with mean time since surgery of 12 years (10 to 14). There were 58 cemented and 21 cementless tibial components. RESULTS: Migration at one year and two years was significantly correlated with long-term migration (p < 0.001). Median migration at the long-term follow-up was 0.6 mm (maximum total point motion; interquartile range (IQR) 0.4 to 0.9) for the cemented group and 0.6 mm (IQR 0.3 to 1.1) for the cementless group with no difference between groups (p = 0.99). Inducible displacement was significantly lower for the cementless components (p < 0.001). CONCLUSION: Long-term migration was strongly correlated with two-year migration. Although long-term migration was not different for cemented or cementless tibial components, inducible displacement at the long-term visit was significantly lower for these cementless components, suggesting superior fixation. These findings support the predictive value of short-term migration in determining long-term fixation. Cite this article: Bone Joint J 2019;101-B(7 Supple C):55-60.


Assuntos
Artroplastia do Joelho/efeitos adversos , Cimentos para Ossos , Previsões , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Complicações Pós-Operatórias , Tíbia/cirurgia , Idoso , Feminino , Seguimentos , Humanos , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Porosidade , Desenho de Prótese , Falha de Prótese , Análise Radioestereométrica , Resultado do Tratamento
16.
Chem Commun (Camb) ; 55(61): 9039-9042, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292589
17.
J Phys Chem Lett ; 10(15): 4185-4191, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295998

RESUMO

The treatment of massive bone defects is still a significant challenge for orthopedists. Here we have engineered synthetic porous AuPd alloy nanoparticles (pAuPds) as a hyperthermia agent for in situ bone regeneration through photothermal therapy (PTT). After being swallowed by cells, pAuPds produced a mild localized heat (MLH) (40-43 °C) under the irradiation of a near-infrared laser, which can greatly accelerate cell proliferation and bone regeneration. Almost 97% of the cranial defect area (8 mm in diameter) was covered by the newly formed bone after 6 weeks of PTT. RNA sequencing analysis was used to obtain insight into the molecular mechanism of the MLH on cell proliferation and bone formation. These results demonstrated that the Wnt signaling pathway was involved in the MLH. This Letter provides a unique strategy with mild heat stimulation and high efficiency for in situ bone regeneration.


Assuntos
Ligas/química , Regeneração Óssea , Ouro/química , Nanopartículas Metálicas/química , Paládio/química , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Hipertermia Induzida , Raios Infravermelhos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/toxicidade , Camundongos , Fototerapia , Porosidade , Ratos , Crânio/patologia
18.
J Phys Chem Lett ; 10(15): 4192-4196, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31305079

RESUMO

We report the successful one-pot synthesis of adenosine mono-, di-, and triphosphate in the confined space of a mordenite zeolite. This is also the first report of ATP synthesized onto a porous mineral surface. The results revealed a plausible prebiotic route to ribonucleotides and highlighted the contribution of microporous minerals in the origins of life.


Assuntos
Difosfato de Adenosina/síntese química , Monofosfato de Adenosina/síntese química , Trifosfato de Adenosina/síntese química , Silicatos de Alumínio/química , Nanopartículas/química , Técnicas de Síntese em Fase Sólida/métodos , Zeolitas/química , Adenina/química , Organofosfatos/química , Origem da Vida , Porosidade , Ribose/química , Propriedades de Superfície , Termodinâmica , Fatores de Tempo
19.
Chem Asian J ; 14(17): 2953-2957, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31321878

RESUMO

This paper describes the synthesis of protein microtube motors having a urease interior surface and highlights their nonbubble-propelled behavior driven by enzymatic reaction (urea→NH3 and CO2 ). The precursor microtubes were prepared by layer-by-layer assembly using a track-etched microporous polycarbonate membrane. Immobilization of a urease on the internal wall was accomplished using avidin-biotin interaction. The tubules swam smoothly in an aqueous media containing a physiological concentration of urea. Each tubule was rotating laterally while moving forward. It is remarkable that the microtubes were digested completely by proteases, demonstrating perfect biodegradability.


Assuntos
Avidina/química , Biotina/química , Urease/metabolismo , Avidina/metabolismo , Biotina/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Cimento de Policarboxilato/química , Porosidade , Ureia/química , Ureia/metabolismo , Urease/química
20.
Anal Chim Acta ; 1078: 125-134, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358210

RESUMO

We synthesized three kinds of nitrogen-doped nanoporous carbon nanomaterials (represented by N-mC) through a cost-effective method, that is, pyrolysis of plant biomasses (grass, flower, and peanut shells). We further explored their potential as sensitive bioplatforms for electrochemical label-free aptasensors to facilitate the early detection of alpha-fetoprotein (AFP). Chemical structure characterizations revealed that rich functional groups coexisted in as-synthesized N-mC nanomaterials, such as C-C, C-O, C=O, C-N, and COOH. Among the three kinds of N-mC nanomaterials, the one derived from grass (N-mCg) exhibited the lowest carbon defect degree, the highest ID/IG ratio in the Raman spectra, and the largest specific surface area (186.2 m2 g-1). Consequently, N-mCg displayed excellent electrochemical activity and strong affinity toward aptamer strands, further endowing the corresponding aptasensor with sensitive detection ability for AFP. Electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) were used to investigate the whole detection procedure for AFP. The EIS and DPV results showed that the fabricated N-mCg-based aptasensor possessed an extremely low limit of detection of 60.8 and 61.8 fg·mL-1 (s/n = 3), respectively, for detecting AFP within a wide linear range from 0.1 pg mL-1 to 100 ng mL-1. Moreover, the aptasensor displayed acceptable selectivity and applicability, high reproducibility, and excellent stability in serum samples of cancer patients. Therefore, the proposed cost-effective and label-free strategy based on the nitrogen-doped nanoporous carbon derived from plant biomass is a promising approach for the early detection of various tumor markers.


Assuntos
Biomassa , Técnicas Biossensoriais/métodos , Carbono/química , Técnicas Eletroquímicas/métodos , Nanoestruturas/química , alfa-Fetoproteínas/análise , Adolescente , Adulto , Idoso , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Técnicas Biossensoriais/instrumentação , DNA/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Nitrogênio/química , Plantas/química , Porosidade , Reprodutibilidade dos Testes , Adulto Jovem
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