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1.
Small ; 20(23): e2307603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38213024

RESUMO

Bacterial cellulose/oxidized bacterial cellulose nanofibrils (BC/oxBCNFs) macro-fibers are developed as a novel scaffold for vascular tissue engineering. Utilizing a low-speed rotary coagulation spinning technique and precise solvent control, macro-fibers with a unique heterogeneous structure with dense surface and porous core are created. Enhanced by a polydopamine (PDA) coating, these macro-fibers offer robust mechanical integrity, high biocompatibility, and excellent cell adhesion. When cultured with endothelial cells (ECs) and smooth muscle cells (SMCs), the macro-fibers support healthy cell proliferation and exhibit a unique spiral SMC alignment, demonstrating their vascular suitability. This innovative strategy opens new avenues for advances in tissue engineering.


Assuntos
Celulose , Nanofibras , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Nanofibras/química , Alicerces Teciduais/química , Celulose/química , Humanos , Miócitos de Músculo Liso/citologia , Proliferação de Células/efeitos dos fármacos , Adesão Celular , Células Endoteliais/citologia , Células Endoteliais da Veia Umbilical Humana , Indóis/química , Polímeros
2.
Clin Exp Rheumatol ; 2024 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-39051168

RESUMO

OBJECTIVES: Patients with fibromyalgia syndrome (FM) often suffer from sleep disorders, adversely affecting their prognosis. Active non-pharmacological therapies are considered the mainstay of treatment for FM, but the optimal treatment choice remains contentious. We aimed to compare and rank community-based non-pharmacological interventions for FM with sleep disorder by quantifying information from randomised controlled trials (RCTs). METHODS: Two authors independently selected studies and extracted data. We searched Embase, MEDLINE, PubMed, CNKI, Scopus, Google Scholar, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) from the database inception to June 2022. Network meta-analyses were conducted using a frequency-based method. The study protocol is registered with the Prospective Register of Systematic Reviews (PROSPERO, CRD 42022373704). Eleven RCTs (n=729) were included in the analysis. RESULTS: Mindfulness-based therapy (MBT) (SMD=-0.84 (95% CI: -1.49 to -0.20)) and cognitive behavioural therapy (CBT) (SMD=-0.54 (95% CI: -1.04 to -0.04)) were associated with significantly improved sleep symptoms in a patient with FM compared with usual care. CONCLUSIONS: MBT exhibited the highest probability (91.14%) of being the most effective intervention in sleep improvement, followed by CBT (72.39%). MBT exhibited marked advantages over other interventions and is likely to have optimal efficacy in ameliorating sleep disorders.

3.
BMC Health Serv Res ; 23(1): 685, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353822

RESUMO

BACKGROUND: There is a serious shortage of clinical pharmacists in Xinjiang, China. A six-month to one-year on-the-job training programme can rapidly transition nonclinical pharmacists into clinical pharmacists to resolve this issue. However, not all nonclinical pharmacists are willing to become clinical pharmacists, and many factors may influence their willingness. This study aims to assess the transformation intention of nonclinical hospital pharmacists and the contributing elements to make recommendations to accelerate the transformation of hospital pharmacists to clinical pharmacists. METHODS: Cross-sectional survey was conducted in secondary and tertiary hospitals in Xinjiang. Taking 14 prefectures in Xinjiang as a cluster, 34 hospitals were randomly selected. By snowball sampling, the heads of pharmaceutical departments introduced non-clinical pharmacists to participate in an anonymous questionnaire survey, which included 41 questions about basic demographic information, cognition and attitudes towards pharmaceutical care, potential factors and willingness to transform, and it took an average of 10 min to complete. Using multifactor logistic regression, the contributing elements of transformation intention were analysed. RESULTS: The survey was conducted from May to October 2022. 338 valid responses were obtained, with a response rate of 91.85% and a willingness to transform rate of 81.67%. There were significant differences in the willingness to transform among nonclinical pharmacists of different ages (P < 0.05), marital statuses (P < 0.05), years of employment (P < 0.05), and technical titles (P < 0.05). There were significant differences between the two groups in the following four aspects: whether the setting of human resources in the pharmaceutical department was reasonable (P < 0.05), the educational level of clinical pharmacists (P < 0.05), the higher salary level of clinical pharmacists (P < 0.05), and whether they had experience in pharmaceutical care (P < 0.05). There was a significant difference in the total score of the pharmaceutical care attitude scale (P < 0.05) between the willing and unwilling groups. The results of multivariate logistic regression analysis revealed that the experience of providing pharmaceutical care (OR = 4.601, 95% CI: 1.13-18.69, P < 0.05) and attitude towards pharmaceutical care (OR = 3.302, 95% CI: 1.19-9.19, P < 0.05) had a statistically significant influence on the transformation intention of nonclinical pharmacists. CONCLUSIONS: One-fifth of nonclinical pharmacists were unwilling to transition to clinical pharmacists. The attitude towards and experience of pharmaceutical care affected pharmacists' transformation intention, so the suggestion is proposed to promote the transformation of nonclinical pharmacists into clinical pharmacists.


Assuntos
Atitude do Pessoal de Saúde , Farmacêuticos , Humanos , Estudos Transversais , Inquéritos e Questionários , China , Preparações Farmacêuticas
4.
Molecules ; 28(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175195

RESUMO

Cerium dioxide (CeO2) was pretreated with reduction and reoxidation under different conditions in order to elucidate the role of surface Ce4+ and oxygen vacancies in the catalytic activity for direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol. The corresponding catalysts were comprehensively characterized using N2 physisorption, XRD, TEM, XPS, TPD, and CO2-FTIR. The results indicated that reduction treatment promotes the conversion of Ce4+ to Ce3+ and improves the concentration of surface oxygen vacancies, while reoxidation treatment facilitates the conversion of Ce3+ to Ce4+ and decreases the concentration of surface oxygen vacancies. The catalytic activity was linear with the number of moderate acidic/basic sites. The surface Ce4+ rather than oxygen vacancies, as Lewis acid sites, promoted the adsorption of CO2 and the formation of active bidentate carbonates. The number of moderate basic sites and the catalytic activity were positively correlated with the surface concentration of Ce4+ but negatively correlated with the surface concentration of oxygen vacancies. The surface Ce4+ and lattice oxygen were active Lewis acid and base sites respectively for CeO2 catalyst, while surface oxygen vacancy and lattice oxygen were active Lewis acid and base sites, respectively, for metal-doped CeO2 catalysts. This may result from the different natures of oxygen vacancies in CeO2 and metal-doped CeO2 catalysts.

5.
Small ; 17(14): e2006955, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33711196

RESUMO

T cell based-immunotherapy has been a powerful strategy to eradicate tumor cells in clinical trials. Effectively expanding the therapeutic T cells for clinical demand is still a challenge. Here, artificial antigen-presenting scaffolds are created for T cell ex vivo expansion. The antigen-presenting hybrid colloidal crystal clusters (HCCCs) with multiple stimuli are generated by internal encapsulation with prosurvival cytokines and surface decoration with activating antibodies to CD3ε and CD28, respectively. With the large loading capacity endowed by their abundant nanoporous structures, the antigen-presenting HCCCs can constantly release prosurvival cytokine IL-2. It is found that following the direct and multiple stimulations, the antigen-presenting HCCCs can effectively promote the expansion of T cells, which exhibits robust antitumor activity in vitro. Thus, the antigen-presenting HCCCs provide a novel expansion platform for clinical manufacturing of T cells.


Assuntos
Células Apresentadoras de Antígenos , Antígenos CD28 , Proliferação de Células , Imunoterapia , Linfócitos T
6.
J Nanobiotechnology ; 19(1): 137, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33985525

RESUMO

Photothermal therapy has attracted extensive attentions in cancer treatment due to its precise spatial-temporal controllability, minimal invasiveness, and negligible side effects. However, two major deficiencies, unsatisfactory heat conversion efficiency and limited tissue penetration depth, hugely impeded its clinical application. In this work, hollow carbon nanosphere modified with polyethylene glycol-graft-polyethylenimine (HPP) was elaborately synthesized. The synthesized HPP owns outstanding physical properties as a photothermal agent, such as uniform core-shell structure, good biocompatibility and excellent heat conversion efficiency. Upon NIR-II laser irradiation, the intracellular HPP shows excellent photothermal activity towards cancer cell killing. In addition, depending on the large internal cavity of HPP, the extended biomedical application as drug carrier was also demonstrated. In general, the synthesized HPP holds a great potential in NIR-II laser-activated cancer photothermal therapy.


Assuntos
Materiais Biocompatíveis , Carbono/química , Nanosferas/química , Fototerapia/métodos , Terapia Fototérmica , Animais , Portadores de Fármacos/química , Humanos , Neoplasias/terapia , Polietilenoglicóis
7.
Proc Natl Acad Sci U S A ; 115(24): 6159-6164, 2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29802229

RESUMO

We investigate the dynamics of an electrified liquid filament in a nozzle-to-substrate configuration with a close separation. The interplay between compressive viscous and electrostatic stresses dictates previously undocumented transitions between dynamic regimes of "jetting," "coiling," and "whipping." In particular, the onsets of both coiling and whipping instabilities are significantly influenced by the minimum radius along the liquid filament. Using a low-interfacial-tension system, we unravel the physics behind the transitions between jetting, coiling, and whipping of an electrified filament for a range of liquid properties and geometric parameters. Our results enrich the overall physical picture of the electrically forced jets, and provide insights for the emerging high-resolution instability-assisted printing of materials such as folded assemblies and scaffolds.

8.
Anal Chem ; 92(4): 2891-2895, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32013396

RESUMO

Multiplexed quantification of mycotoxins is of great significance in food safety. Here, novel photonic crystal (PhC) barcodes with G-quadruplex aptamer encapsulated for label-free multiplex mycotoxins quantification are developed. The probes are immobilized on PhC barcodes to form a molecular beacon (MB), which contains the sequences of mycotoxin aptamers and a G-quadruplex. In the presence of the target, the hairpin structure of MB would open and the region of the G-quadruplex is exposed, which subsequently combines with Thioflavin T (ThT) to produce fluorescence. The relative fluorescence intensity increased as the mycotoxins concentration increased in a linear range from 1.0 pg/mL to 100 ng/mL. Moreover, the multiplexed mycotoxins quantification could be achieved by tuning the structural color of the PhC barcodes. We demonstrate that this method with high accuracy and specificity for multiplexed detection of mycotoxins, with the sensitivity of the detection as low as 0.70 pg/mL. Our results show that G-quadruplex-encapsulated PhC barcodes offer a novel simple and label-free pathway toward the multiplex screen assay of mycotoxins for food safety.


Assuntos
Micotoxinas/análise , Fótons , Aptâmeros de Nucleotídeos/química , Benzotiazóis/química , Técnicas Biossensoriais , Corantes Fluorescentes/química , Quadruplex G , Tamanho da Partícula , Propriedades de Superfície
9.
Small ; 16(9): e1903899, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31747120

RESUMO

Cancer remains the leading cause of death worldwide despite the enormous efforts that are made in the development of cancer biology and anticancer therapeutic treatment. Furthermore, recent studies in oncology have focused on the complex cancer metastatic process as metastatic disease contributes to more than 90% of tumor-related death. In the metastatic process, isolation and analysis of circulating tumor cells (CTCs) play a vital role in diagnosis and prognosis of cancer patients at an early stage. To obtain relevant information on cancer metastasis and progression from CTCs, reliable approaches are required for CTC detection and isolation. Additionally, experimental platforms mimicking the tumor microenvironment in vitro give a better understanding of the metastatic microenvironment and antimetastatic drugs' screening. With the advancement of microfabrication and rapid prototyping, microfluidic techniques are now increasingly being exploited to study cancer metastasis as they allow precise control of fluids in small volume and rapid sample processing at relatively low cost and with high sensitivity. Recent advancements in microfluidic platforms utilized in various methods for CTCs' isolation and tumor models recapitulating the metastatic microenvironment (tumor-on-a-chip) are comprehensively reviewed. Future perspectives on microfluidics for cancer metastasis are proposed.


Assuntos
Separação Celular , Técnicas Analíticas Microfluídicas , Microfluídica , Neoplasias , Células Neoplásicas Circulantes , Separação Celular/métodos , Humanos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/tendências , Microfluídica/instrumentação , Microfluídica/métodos , Microfluídica/tendências , Neoplasias/diagnóstico
10.
Brain Behav Immun ; 89: 623-627, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32717405

RESUMO

BACKGROUNDS: Cigarette smoking has been shown to be associated with sleep disorders and the related neuropathogenesis including neuroinflammation. Previous studies showed that pro- and anti-inflammatory cytokines are physiologically important in maintaining circadian function. In addition, sleep deprivation leads to immune dysregulations. However, no study has been published yet by using cerebrospinal fluid (CSF) biomarkers of neuroinflammation to investigate the relationship between active cigarette smoking and sleep disorders. METHODS: CSF tissues from subjects of 191 male subjects (non-smokers n = 104; active smokers n = 87) receiving local anesthesia before surgery for anterior cruciate ligament injuries were obtained after the assessment of clinical information and Pittsburgh Sleep Quality Index (PSQI). The levels of tumor necrosis factor alpha (TNFα), Interleukin (IL) 1 beta (IL1ß), IL2, IL4, IL6 and IL10 were measured using radioimmunoassay and ELISA. RESULTS: PSQI scores were significantly higher in active smokers than that in non-smokers (p < 0.001, Cohen's d = 0.63). Significantly higher levels of CSF TNFα were found in active smokers compared to non-smokers (28 ± 1.97 vs. 22.97 ± 2.48, p < 0.05, Cohen's d = 2.23). There was a positive correlation between CSF IL1ß levels and PSQI scores in non-smokers (r = 0.31, p = 0.01, adjustment R-Squared = 0.11). DISCUSSION: This is the first study to reveal the association between higher CSF TNFα levels and poorer sleep quality in active smoking. In addition, CSF IL1ß levels might be a potential biomarker in central nervous system for circadian dysregulation.


Assuntos
Fumar Cigarros , Transtornos do Sono-Vigília , Biomarcadores , Humanos , Masculino , Privação do Sono , Fumar
11.
Langmuir ; 36(28): 8165-8173, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32575990

RESUMO

Microencapsulation of phase-change materials (PCMs) can prevent leakage of PCMs and enhance heat transfer with an increased surface area to volume ratio and thus benefit their pragmatic applications. However, the available methods have difficulties in microencapsulating PCMs with a tunable size, structure, and composition at will, thereby failing to accurately and flexibly tailor the thermal properties of microencapsulated PCMs (MEPCMs). Here, the microfluidic encapsulation of PCMs was presented for precisely fabricating MEPCMs with tunable thermal properties. The versatile fabrication of both organic and inorganic MEPCMs was demonstrated with high monodispersity, energy storage capacity, encapsulation efficiency, thermal stability, reliability, and heat charging and discharging rates. Notably, the inorganic MEPCMs exhibit an energy storage capacity of 269.3 J/g and a charging rate of 294.7 J/(g min), surpassing previously reported values. Owing to their high thermal performance, MEPCMs have been used for anticounterfeit applications. Droplet-based microfluidic fabrication opens up a new avenue for versatile fabrication of MEPCMs with well-tailored thermal properties, thus benefitting their applications.

12.
Soft Matter ; 16(37): 8526-8546, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32945331

RESUMO

Electrohydrodynamics is among the most promising techniques for manipulating liquids in microsystems. The electric stress actuates, generates, and coalesces droplets of small sizes; it also accelerates, focuses, and controls the motion of fine jets. In this review, the current understanding of dynamic regimes of electrically driven drops and jets in multiphase microsystems is summarized. The experimental description and underlying mechanism of force interplay and instabilities are discussed. Conditions for controlled transitions among different regimes are also provided. Emerging new phenomena either due to special interfacial properties or geometric confinement are emphasized, and simple scaling arguments proposed in the literature are introduced. The review provides useful perspectives for investigations involving electrically driven droplets and jets.

13.
Mikrochim Acta ; 187(9): 513, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32833099

RESUMO

Enabled by the coffee-ring effect, a paper-based signal transduce method is employed for catalytic hairpin assembly (CHA) amplification and hybridization chain reaction (HCR) to achieve miRNA quantification. Once the target miRNAs appeared, it was circularly used by CHA to initiate HCR amplification to produce a large number of G-quadruplex, which is combined with hemin to form a hemin/G-quadruplex DNAzyme. The DNAzyme catalyzes a colorimetric reaction to produce colored nanoparticles, which were converted to the end edge of the paper by evaporation-driven flow, forming a visible colored band. Higher concentration of miRNA led to more colored nanoparticles and thus a longer colored band that can simply be measured by a ruler. The results of determination of miRNA in samples demonstrate that the relative standard deviation of the proposed approach is 5.2%, highly sensitive and repeatable, with a working range 1.0 to 1000 pM and a LOD of 0.2 pM. The paper-based analytical device as a novel platform offers a new signal transduce pathway toward the detection of low-abundance biomarkers for diagnosis.Graphical abstract Schematic representation of the principle for quantification of miRNA on paper based on the coffee-ring effect.


Assuntos
Colorimetria/métodos , MicroRNAs/sangue , Papel , Biomarcadores Tumorais/sangue , Colorimetria/instrumentação , Sondas de DNA/química , DNA Catalítico/química , Quadruplex G , Hemina/química , Humanos , Iodo/química , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
14.
Mikrochim Acta ; 187(6): 348, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32462225

RESUMO

A biomimetic antibody is described for colorimetric determination of glycoprotein, and horseradish peroxidase (HRP) is used as model analyte. Use is made of oriented surface imprinted inverse opal hydrogel particles functionalized with phenylboronic acid. The inverse opal hydrogel particles were negatively replicated from silica colloidal crystal beads (SCCBs), so that they were endowed with larger specific surface area than the bulk structure. Benefit from that, there were abundant surface molecularly imprinting sites in the hydrogel particles. Because the imprinting sites match the structure of the template molecules, they can recognize HRP with high selectivity and sensitivity. The recognized glycoprotein was bonded with the phenylboronic acid within the sites. The bonded HRP was determined by colorimetry of 3, 3', 5, 5'-tetramethylbenzidine (TMB) single-component solution at 450 nm, and it shows a 16.03 imprinting factor under optimized conditions. Alpha-fetoprotein (AFP) was also investigated and demostrated the value of this strategy in practical applications. The results show that the absorbance increases linearly in the 1-50 ng mL-1 AFP concentration range and has a 1.32 ng mL-1 detection limit. The assay of human serum was realized by the standard addition method. This strategy is promising to open new horizons for glycoprotein assay. Graphical abstract Schematic representation of the preparation of oriented boronate affinity-imprinted inverse opal hydrogel particles for glycoprotein assay.


Assuntos
Ácidos Borônicos/química , Glicoproteínas/análise , Peroxidase do Rábano Silvestre/análise , Hidrogéis/química , Dióxido de Silício/química , Armoracia/enzimologia , Materiais Biomiméticos/química , Colorimetria/métodos , Impressão Molecular , Estudo de Prova de Conceito
15.
Small ; 15(39): e1902691, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31410999

RESUMO

2D crystals are emerging new materials in multidisciplinary fields including condensed state physics, electronics, energy, environmental engineering, and biomedicine. To employ 2D crystals for practical applications, these nanoscale crystals need to be processed into macroscale materials, such as suspensions, fibers, films, and 3D macrostructures. Among these macromaterials, fibers are flexible, knittable, and easy to use, which can fully reflect the advantages of the structure and properties of 2D crystals. Therefore, the fabrication and application of 2D crystal-based fibers is of great importance for expanding the impact of 2D crystals. In this Review, 2D crystals that are successfully prepared are overviewed based on their composition of elements. Subsequently, methods for preparing 2D crystals, 2D crystals dispersions, and 2D crystal-based fibers are systematically introduced. Then, the applications of 2D crystal-based fibers, such as flexible electronic devices, high-efficiency catalysis, and adsorption, are also discussed. Finally, the status-of-quo, perspectives, and future challenges of 2D crystal-based fibers are summarized. This Review provides directions and guidelines for developing new 2D crystal-based fibers and exploring their potentials in the fields of smart wearable devices.

16.
Small ; 15(3): e1804549, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30548921

RESUMO

Understanding the mechanical stability of granular-armored liquid marbles is prerequisite for their applications including encapsulation, sensors, microreactions, and miniaturized liquid storage. Most liquid marbles are armored with agglomerated granular structure which complicates the wetting and interacting states of particles, hence, impeding one from understanding the effect of granular size on the mechanical stability of marbles. In this work, using a custom-built platform to examine the liquid marbles armored by a single layer of uniform grains, it is revealed that larger microsized grains produce stronger liquid marble. This finding is attributed to the gravity-induced capillary attraction which dominates the interaction of particles and provides additional tension to the granular network of the marble surface, which enhances the mechanical stability of marbles. In addition, different granular network structures are formed at the marble surface by using a binary mixture of monodisperse grains, and their effect on the mechanical stability of marbles is explored. The understandings offer important insights for application involving liquid marbles and provides guideline to formulate robust marble-based products.

17.
Angew Chem Int Ed Engl ; 58(32): 10951-10955, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31179608

RESUMO

Sponges, Neofibularia nolitangere, can regenerate spontaneously after being broken down into small pieces, and the regenerated structure maintains the original appearance and function. Synthetic materials with such capabilities are highly desired but hardly achieved. Presented here is a sponge-inspired self-regenerative powder from a double-network (DN) tough hydrogel. Hydrogels are regenerated from their powder form, by addition of water, with preservation of the original appearance and mechanical properties. The powder-hydrogel-powder cycle can be repeated multiple times with little loss in mechanical properties, analogous to the regeneration of sponges. These DN hydrogels can be conveniently stored and easily shaped upon regeneration. This work may have implications in the development of regenerative materials for coatings and adhesives.


Assuntos
Hidrogéis/síntese química , Poríferos/química , Animais , Configuração de Carboidratos , Hidrogéis/química , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
18.
Small ; 14(37): e1802902, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30129255

RESUMO

Studying the stability of Pickering emulsion is of great interest for applications including catalysis, oil recovery, and cosmetics. Conventional methods emphasize the overall behavior of bulk emulsions and neglect the influence of particle adsorbing dynamics, leading to discrepancies in predicting the shelf-life of Pickering emulsion-based products. By employing a microfluidic method, the particle adsorption is controlled and the stability of the Pickering emulsions is consequently examined. This approach enables us to elucidate the relationship between the particle adsorption dynamics and the stability of Pickering emulsions on droplet-level quantitatively. Using oil/water emulsions stabilized by polystyrene nanoparticles as an example, the diffusion-limited particle adsorption is demonstrated and investigated the stability criteria with respect to particle size, particle concentration, surface chemistry, and ionic strength. This approach offers important insights for application involving Pickering emulsions and provides guidelines to formulate and quantify the Pickering emulsion-based products.

19.
Langmuir ; 34(30): 8785-8791, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-29983067

RESUMO

We demonstrate hierarchical nest/crust-like colloidosomes composed of interlocked titanium dioxide (TiO2) nanofibers using spontaneously evolved n-butanol/water/ n-butanol (B/W/B) emulsions. We find two mechanisms to produce colloidosomes from B/W/B droplets due to their mutual solubility and dewetting discrepancy. Porous TiO2 colloidal capsules with loosely intertwined nanofibers were obtained after the dewetting of nanofiber-coated B/W/B droplets, while crustlike TiO2 colloidosomes with a thin shell and large hollow interior are developed from amphiphilic polymer-stabilized B/W/B droplets. We further investigate the effect of experimental parameters, including the initial droplet size, the nanofiber concentration, and the water/butanol ratios in butanol phases, on the droplet-to-colloidosome evolution and resultant morphology of colloidosomes. Our simple and versatile approach for fabricating TiO2 colloidosomes can be extended to a range of irregular colloidal particles, and the products have great potential to act as host systems in electrochemical catalysis, photothermal therapy, or filtration materials.

20.
Langmuir ; 34(4): 1419-1428, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29251943

RESUMO

In this Article, we report the synthesis of micro- and nanocrystalline diamond/ß-SiC composite gradient films, using a hot filament chemical vapor deposition (HFCVD) technique and its application as a robust and chemically inert means to actuate water and hazardous liquids. As revealed by scanning electron microscopy, the composition of the surface changed gradually from pure nanocrystalline diamond (hydrophobic) to a nanocrystalline ß-SiC surface (hydrophilic). Transmission electron microscopy and Raman spectroscopy were employed to determine the presence of diamond, graphite, and ß-SiC phases. The as-prepared gradient films were evaluated for their ability to actuate water. Indeed, water was transported via the gradient from the hydrophobic (hydrogen-terminated diamond) to the hydrophilic side (hydroxyl-terminated ß-SiC) of the gradient surface. The driving distance and velocity of water is pivotally influenced by the surface roughness. The nanogradient surface showed significant promise as the lower roughness combined with the longer gradient yields in transport distances of up to 3.7 mm, with a maximum droplet velocity of nearly 250 mm/s measured by a high-speed camera. As diamond and ß-SiC are chemically inert, the gradient surfaces can be used to drive hazardous liquids and reactive mixtures, which was signified by the actuation of hydrochloric acid and sodium hydroxide solution. We envision that the diamond/ß-SiC gradient surface has high potential as an actuator for water transport in microfluidic devices, DNA sensors, and implants, which induce guided cell growth.

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