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1.
Nat Commun ; 11(1): 1604, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32231216

RESUMO

Conducting polymers are promising material candidates in diverse applications including energy storage, flexible electronics, and bioelectronics. However, the fabrication of conducting polymers has mostly relied on conventional approaches such as ink-jet printing, screen printing, and electron-beam lithography, whose limitations have hampered rapid innovations and broad applications of conducting polymers. Here we introduce a high-performance 3D printable conducting polymer ink based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) for 3D printing of conducting polymers. The resultant superior printability enables facile fabrication of conducting polymers into high resolution and high aspect ratio microstructures, which can be integrated with other materials such as insulating elastomers via multi-material 3D printing. The 3D-printed conducting polymers can also be converted into highly conductive and soft hydrogel microstructures. We further demonstrate fast and streamlined fabrications of various conducting polymer devices, such as a soft neural probe capable of in vivo single-unit recording.


Assuntos
Polímeros/química , Impressão Tridimensional , Elastômeros/química , Condutividade Elétrica , Eletrônica , Hidrogéis/química , Tinta , Poliestirenos/química , Impressão
3.
Macromol Rapid Commun ; 41(5): e1900555, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003532

RESUMO

Structured color in nature is controlled by nano- and micro-structured interfaces giving rise to a photonic bandgap. This study presents a biomimetic optical material based on polymeric inverse opals that respond to enzyme activity. Polymer colloids provide a template in which acryloyl-functionalized poly(ethylene glycol) is integrated; dissolution of the colloids leads to a hydrogel inverse opal that can be lithographically patterned using transfer printing. Incorporating enzyme substrates within the voids provides a material that responds to the presence of proteases through a shift in the optical properties.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Nanoestruturas/química , Peptídeo Hidrolases/metabolismo , Polímeros/química , Materiais Biomiméticos/química , Coloides/química , Cor , Iridescência , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Fótons , Polietilenoglicóis/química , Polimetil Metacrilato/química , Impressão
4.
Nat Commun ; 11(1): 1002, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081910

RESUMO

Innovations in soft material synthesis and fabrication technologies have led to the development of integrated soft electronic devices. Such soft devices offer opportunities to interact with biological cells, mimicking their soft environment. However, existing fabrication technologies cannot create the submicron-scale, soft transducers needed for healthcare and medical applications involving single cells. This work presents a nanofabrication strategy to create submicron-scale, all-soft electronic devices based on eutectic gallium-indium alloy (EGaIn) using a hybrid method utilizing electron-beam lithography and soft lithography. The hybrid lithography process is applied to a biphasic structure, comprising a metallic adhesion layer coated with EGaIn, to create soft nano/microstructures embedded in elastomeric materials. Submicron-scale EGaIn thin-film patterning with feature sizes as small as 180 nm and 1 µm line spacing was achieved, resulting in the highest resolution EGaIn patterning technique to date. The resulting soft and stretchable EGaIn patterns offer a currently unrivaled combination of resolution, electrical conductivity, and electronic/wiring density.


Assuntos
Equipamentos e Provisões Elétricas , Eletrônica/instrumentação , Metais , Nanotecnologia/métodos , Ligas , Elastômeros , Condutividade Elétrica , Desenho de Equipamento , Gálio , Índio , Indústria Manufatureira/métodos , Impressão , Propriedades de Superfície
5.
Indoor Air ; 30(3): 396-421, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31944398

RESUMO

Many studies have shown that the use of laser printing devices (LPDs) contributes to the release of particles into the indoor environment. However, after more than two decades of research, the physicochemical properties of LPD-emitted particles and the possible health effects from exposure to particles are still heavily debated. We therefore carried out a critical review of the published studies around emissions and health effects of LPD-emitted particles, aiming at elucidating the nature of these particles and their potential health risks. Realizing the varying methodologies of the studies, a classification of the reviewed studies is adopted, resulting in three categories of emission studies (chamber experiment, office/room measurement, and photocopy shop measurement), and three types of health studies (in vitro/animal studies, human studies in the real world, and human studies in controlled settings). The strengths and limitations of each type of study are discussed in-depth, which in turn helps to understand the cause of divergent results. Overall, LPD-emitted particles are mainly condensed or secondary-formed semi-volatile organic compounds (SVOCs), while solid toner particles account for a very small fraction. The health risk from exposure to LPD-emitted particles is small compared with the health risk from exposure to ambient particles.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Impressão , Compostos Orgânicos Voláteis , Poluentes Atmosféricos , Humanos , Tamanho da Partícula , Material Particulado
6.
Carbohydr Polym ; 230: 115603, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887950

RESUMO

Invisible high-security anticounterfeiting inks were developed by surface-modification of functionalized latex nanoparticles with spiropyran derivatives, which display both photochromism and fluorescence upon UV irradiation at the same time. The functionalized latex nanoparticles show different spherical, doughnut-like, and red blood cell-like morphologies depending on concentration and type of its functional groups. Microscopic investigation of the impregnated cellulosic papers with latex nanoparticles display that epoxy-functionalized spherical latex nanoparticles have considerable packing and stability on the surface of the cellulosic substrate by formation of hydrogen bonding. Epoxy-functionalized latex nanoparticles containing spiropyran were used for preparation of high-security photochromic/fluorescent anticounterfeiting inks for print-marking of different cellulosic security documents such as certificate, money, and passport with different marks. The printed marks and finger-prints on the cellulosic security documents display photochromism and red fluorescence emission upon UV irradiation with high intensity and brightness.


Assuntos
Celulose/química , Nanopartículas/química , Papel/normas , Impressão/métodos , Polímeros Responsivos a Estímulos/química , Benzopiranos/química , Fluorescência , Ligação de Hidrogênio , Indóis/química , Tinta , Látex/química , Nitrocompostos/química
7.
Talanta ; 207: 120349, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594572

RESUMO

In this work, for the first time, the direct usability of natural products, catechins (CT) and cocoa powder (CO), as electrochemical mediators able to modify a carbon black modified screen-printed electrode (SPE-CB) is proved, and, as proof of applicability, free (GSH) and total glutathione (GSH + GSSG) in blood samples is successfully determined. Noteworthy, the cocoa powder (naturally rich in catechins), dissolved in DMSO, was able to give rise to a useful highly redox-active catechol-quinone surface-confined system onto a carbon black nanoparticles modified screen-printed electrode (SPE-CB-CO - Cocoatrode), giving rise to a similar behaviour obtained with pure catechins (SPE-CB-CT). The electrodeposition process has been carefully studied, the resulting immobilized natural mediator (obtained using both CT and CO) features investigated, and the performance of the resulting sensors (SPE-CB-CT and Cocoatrode) tested and compared. Both modified electrodes (SPE-CB-CT and Cocoatrode) have a good inter-electrodes precision (RSD ip,a ≤ 4.2%, n = 3) and intra-electrodes repeatability (RSD ip,a ≤ 3.9%, n = 20), indicating a robust and stable 'fabrication' strategy. Finally, SPE-CB-CT and Cocoatrode have been employed for the detection of free (GSH) and total (GSH+GSSG) glutathione in blood samples, using differential pulse voltammetry decrease in the mediator's reduction peak (Δi %), as analytical signal. Analytical curves (R2 ≥ 0.998), for the GSH detection, have been determined both with SPE-CB-CT and Cocoatrode in the 2.5 × 10-8-6.0 × 10-5 M and 5.0 × 10-8-1.0 × 10-4 M concentration ranges, respectively. Limits of detections (LODs) were ≤2.6 × 10-8 M. GSH (free and total) determined in blood samples, by the proposed CT and CO sensors, showed a good intra-electrode repeatability (RSD ip,a ≤ 9.0%, n = 3), with good recoveries (from 88.3% to 117.7%). The values obtained were in agreement with a classical spectrophotometric method (GSH and GSSG concentration relative error between -4.7 and +9.8%). The SPE-CB-CT and the Cocoatrode platforms demonstrated high potentiality in sensing and biosensing scenario, opening new gates to the natural/food products employment as unconventional, eco-friendly and economically affordable analytical active tools.


Assuntos
Análise Química do Sangue/instrumentação , Catequina/química , Chocolate , Glutationa/sangue , Impressão , Fuligem/química , Eletroquímica , Eletrodos , Glutationa/química
8.
Talanta ; 207: 120299, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594611

RESUMO

Analysis on mixture toxicity (Mix-tox) of the multi-chemical space is constantly followed with interest for many researchers. Conventional toxicity tests with time-consuming and costly operations make researchers can only establish some toxicity prediction models aiming to a limited sampling dimension. The rapid development of machine learning (ML) algorithm will accelerate the exploration of many fields involving toxicity analysis. Rather than the model calculation capacity, the challenge of this process mainly comes from the lack of toxicology big-data to perform toxicity perception through the ML model. In this paper, a full strategy based a standardized high-throughput experiment was developed for Mix-tox analysis throughout the whole routine, from big-sample dataset design, model building, and training, to the toxicity prediction. Using the concentration variates as input and bio-luminescent inhibition rate as output, it turned out that a well-trained random forest algorithm was successfully applied to assess the mixtures' toxicity effect, suggesting its value in facilitating adoption of Mix-tox analysis.


Assuntos
Aprendizado de Máquina , Impressão , Testes de Toxicidade/instrumentação
9.
Talanta ; 207: 120277, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594622

RESUMO

A low-cost and disposable microcell was constructed with a screen-printed electrode for the non-enzymatic electrochemical determination of creatinine. The working electrode was modified with carbon black and maintained in contact with paper-adsorbed iron (III) ions. A small sample volume of 3 µL was required for the device operation. Then, iron (III) ions were complexed in the presence of creatinine in a chemical step, followed by an electrochemical reduction of non-complexed metallic ions in excess. Cyclic voltammetry and differential-pulse voltammetry experiments were employed for the electrochemical characterizations and analytical performance evaluation of the microcell. The working electrode modification with carbon black provided a significant increase of analytical signal. The sensor presented a linear response for creatinine concentrations ranging from 0.10 to 6.5 mmol L-1, with a limit of detection of 0.043 mmol L-1. Experiments for creatinine determination in real samples were successful performed through of standard recovery in urine.


Assuntos
Creatinina/análise , Eletroquímica/instrumentação , Análise em Microsséries/instrumentação , Impressão , Creatinina/química , Creatinina/urina , Eletrodos , Química Verde , Humanos , Ferro/química , Limite de Detecção , Fuligem/química
10.
Talanta ; 208: 120389, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816713

RESUMO

In this work, we developed an effective voltammetric immunosensing platform for the sensitive detection of prostate specific antigen (PSA) utilizing a graphene oxide (GO) modified screen-printed carbon electrode (SPCE) hybridized with the ex-situ prepared silver nanoparticles (AgNPs) as a probe and signal transducer. The sensing platform comprises a direct-type immunoassay involving the selective interaction of PSA with anti-PSA. The surface morphology and analytical performance of the modified SPCE were characterized through relevant instrumentations. The changes in the voltammetric reduction current of AgNPs at 0.11 V in the sensor electrode was correlated to the PSA concentration. Under optimum conditions, the fabricated immunosensor exhibited a sensitive response to PSA with a limit of detection (LOD) of 0.27 ng mL-1 and a dynamic calibration range of 0.75-100.0 ng mL-1. We demonstrated that the participation of AgNPs along with GO modification contribute to the desired signal amplification and sensitive detection of PSA. It is anticipated that the proposed immunosensor can serve as a biomarker and potentially be utilized for the real sample quantification of PSA.


Assuntos
Carbono/química , Grafite/química , Imunoensaio/instrumentação , Limite de Detecção , Nanoestruturas/química , Antígeno Prostático Específico/análise , Prata/química , Eletroquímica , Eletrodos , Humanos , Impressão , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/química
11.
Med. UIS ; 32(3): 49-54, Sep.-Dec. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1114976

RESUMO

Resumen La luxación temporomandibular es infrecuente, pero genera gran repercusión en el esqueleto facial. En ocasiones el cuadro clínico inicial es inespecífico y puede confundirse con otras patologías si no se tiene un adecuado conocimiento del tema, o se realiza una anamnesis incorrecta. Este artículo presenta el caso de una paciente que consultó al servicio de urgencias por disartria y desviación de la comisura labial hacia la izquierda, asociado a dolor severo y parestesia en hemicara derecha. No obstante, al ingreso la paciente refirió síntomas ambiguos, que para el médico evaluador sugirieron una causa neurológica. Durante la observación se solicitó valoración por servicio de cirugía plástica, se logró orientación de la anamnesis y examen físico, obteniendo una impresión diagnóstica de luxación de articulación temporomandibular derecha, confirmada por imagenología, y por ende un tratamiento oportuno con reducción e inmovilización en el servicio de urgencias. MÉD.UIS.2019;32(3):49-54


Abstract The temporomandibular joint dislocation is uncommon, but it causes a great repercussion on the facial skeleton. Occasionally, the initial symptoms can be unspecific and confuse with other pathologies if there are not an adequate knowledge of the topic and the anamnesis is incorrect. This article presents a clinical case of a patient with dysarthria and left deviation of the labial commissure, associated with severe pain and paresthesia in the right side of the face. Nevertheless, the patient initially referred ambiguous symptoms, suggesting a neurological cause. During observation in the emergency room, plastic surgery service valorated the patient, with subsequent orientation of the anamnesis and physical examination, achieving a satisfactory management of the acute dislocation. MÉD.UIS.2019;32(3):49-54


Assuntos
Humanos , Feminino , Adulto , Transtornos da Articulação Temporomandibular , Luxações Articulares , Dor , Parestesia , Patologia , Exame Físico , Impressão , Esqueleto , Cirurgia Plástica , Articulação Temporomandibular , Disartria , Face , Imobilização , Anamnese
13.
Molecules ; 24(19)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31574997

RESUMO

We report a fabrication method of the conductive pattern based on in situ reactive silver precursor inks by inkjet printing. The reactive silver precursor inks were prepared with ethylene glycol and deionized water mixture as the solvent, and silver nitrate as silver source. Sodium borohydride solution as the reducing agent was first coated on photographic paper by screen printing process, and then dried at 50 °C for 4 h. Furthermore, the reactive silver precursor inks were printed on a photographic paper coated with sodium borohydride using inkjet printing to form silver nanoparticles in situ due to redox reaction, and thus a conductive pattern was obtained. The effects of the reactive silver precursor ink concentration and printing layer number and treatment temperature on the electrical properties and microstructures of the printed patterns were investigated systematically. The size range of in situ-formed silver nanoparticles was 50-90 nm. When the reactive silver precursor ink concentration was 0.13 g/mL, the five-layer printed pattern exhibited a sheet resistance of 4.6 Ω/γ after drying at room temperature for 2 h; furthermore, the sheet resistance of the printed pattern decreased to 1.4 Ω/γ after drying at 130 °C for 2 h. In addition, the display function circuit was printed on the photographic paper to realize the display of the numbers 0-99. It provides new research ideas for the development of environmentally friendly and low-cost flexible paper-based circuits.


Assuntos
Tinta , Impressão , Algoritmos , Modelos Químicos
14.
Sensors (Basel) ; 19(18)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514303

RESUMO

Detection of mycotoxins, especially aflatoxin M1 (AFM1), in milk is crucial to be able to guarantee food quality and safety. In recent years, biosensors have been emerging as a fast, reliable and low-cost technique for the detection of this toxin. In this work, flexible biosensors were fabricated using dispense-printed electrodes, which were functionalized with single-walled carbon nanotubes (SWCNTs) and subsequently coated with specific antibodies to improve their sensitivity. Next, the immunosensor was tested for the detection of AFM1 in buffer solution and a spiked milk sample using a chronoamperometric technique. Results showed that the working range of the sensors was 0.01 µg/L at minimum and 1 µg/L at maximum in both buffer and spiked milk. The lower limit of detection of the SWCNT-functionalized sensor was 0.02 µg/L, which indicates an improved sensitivity compared to the sensors reported so far. The sensitivity and detection range were in accordance with the limitation values imposed by regulations on milk and its products. Therefore, considering the low fabrication cost, the ease of operation, and the rapid read-out, the use of this sensor could contribute to safeguarding consumers' health.


Assuntos
Aflatoxina M1/análise , Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Leite/química , Impressão , Animais , Tampões (Química) , Eletrodos , Microscopia de Força Atômica , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Maleabilidade , Padrões de Referência , Soluções
15.
ACS Appl Mater Interfaces ; 11(40): 37330-37337, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31525871

RESUMO

Blu-ray discs (BDs) are advantageous in comparison with other optical discs (compact discs and digital versatile discs) in terms of not only their storage capacity but also the high-quality materials fabricated from. We have recently discovered that the "Hard Coat" film of Verbatim BDs is in fact a unique type of polymeric substrates that can be readily activated and adapted for biochip fabrications. Particularly, the Hard Coat film peeled from BDs is optically transparent without any fluorescence background, which can be activated by treating with a common base (1.0 M NaOH) at a slightly elevated temperature (55 °C). The surface density of reactive carboxylic acid groups generated, 6.6 ± 0.7 × 10-9 mol/cm2, is much higher than that on polycarbonate upon UV/ozone irradiation (4.8 ± 0.2 × 10-10 mol/cm2). There are no significant physical damages to the substrate morphology, and the aging effect is minimal. More importantly, the BD substrate can be patterned using either cut-out filter paper masks or microfluidic channel plates; both are lithography-free, bench-top methods that facilitate the device fabrication in a common laboratory setting. With classical biotin-streptavidin binding and DNA hybridization arrays as trial systems, we have also demonstrated this new type of biochip substrates for quantitative assay applications.


Assuntos
Procedimentos Analíticos em Microchip/métodos , Impressão , Biotina/química , Estreptavidina/química , Propriedades de Superfície
16.
ACS Appl Mater Interfaces ; 11(40): 37043-37050, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31518103

RESUMO

As practical interest in stretchable electronics increases for future applications in wearables, healthcare, and robotics, the demand for electrical interconnects with high electrical conductivity, durability, printability, and adhesion is growing. Despite the high electrical conductivity and stretchability of most previous interconnects, they lack stable conductivity against strain and adhesion to stretchable substrates, leading to a limitation for their practical applications. Herein, we propose a stretchable conductive adhesive consisting of silver particles with carbon nanotube as an auxiliary filler in silicone adhesives. The conductive adhesive exhibits a high initial conductivity of 6450 S cm-1. They show little change in conductivity over 3000 stretching cycles at 50% strain, currently the highest stability reported for elastic conductors. Based on strong adhesion to stretchable substrates, the gel-free, dry adhesives printed on an elastic bandage for electrocardiography monitoring exhibit an extremely stable performance upon movement of the subject, even after several cycles of detachment-reattachment and machine washing.


Assuntos
Adesivos/química , Condutividade Elétrica , Eletrônica , Impressão , Têxteis , Eletrodos , Silicones/química
17.
ACS Appl Mater Interfaces ; 11(40): 36420-36427, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31509376

RESUMO

Photothermal conversion effect of plasmonic nanostructures is considered as a promising technique for cellular and molecular manipulations owing to controllability of local temperature. Therefore, this technique has been extensively applied to biological studies such as controlling cellular behavior, delivery of biologics, and biomolecular detection. Herein, we propose a novel method for directed cell positioning and photothermally modulated molecular delivery to the cells using patterned plasmonic interfaces. Plasmonic substrates with gold nanorods (GNRs) and cell adhesion molecules fabricated by microcontact printing are optimized for cellular positioning on designated patterns. Through the photothermal conversion effect of GNRs on the pattern, we further demonstrate on-demand, light-induced delivery of drug molecules to the target cells. We expect that this approach will provide a new way to study single cellular behaviors and enhance molecular delivery to the target cells.


Assuntos
Sistemas de Liberação de Medicamentos , Hipertermia Induzida , Fototerapia , Linhagem Celular Tumoral , Ouro/química , Humanos , Nanotubos/química , Nanotubos/ultraestrutura , Impressão
18.
Biomed Microdevices ; 21(3): 64, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273462

RESUMO

Sample deposition based on micro-droplet ejection has broad application prospects in the field of biomedicine. Ejection of RPMI-1640 medium (with and without cells) is investigated experimentally using a home-build electrohydrodynamic (EHD) ejection system, consisting of a liquid supplier and a nozzle, a high voltage source, a droplet collector, and a high speed photography module. High electric voltage is applied between the nozzle and the droplet collector. The liquid surface is electrically charged and the ejection takes place when electric force overcomes the surface tension. The ejection process is studied by using high speed photography and image processing. At low voltage, a stable ejection state is established with ejection frequency ranging from a few to a few tens of Hertz. At high voltage, another stable ejection state is reached with ejection frequency as high as 1300 Hz. At the transition voltage range, the ejection exhibits a periodic behaviour. During each cycle, the meniscus rapidly oscillates with gradually increased amplitude, and with several non-uniform droplets ejected at the final stage of the cycle. Human peripheral blood mononuclear cells, after ejection, shows survival rates higher than 79%, manifesting EHD ejection as a promising technique for cell printing.


Assuntos
Meios de Cultura , Técnicas Citológicas/instrumentação , Eletricidade , Hidrodinâmica , Cinética , Impressão/instrumentação
19.
ACS Appl Mater Interfaces ; 11(31): 28449-28460, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287949

RESUMO

Nanofluidic systems offer a huge potential for discovery of new molecular transport and chemical phenomena that can be employed for future technologies. Herein, we report on the transport behavior of surface-reactive compounds in a nanometer-scale flow of phospholipids from a scanning probe. We have investigated microscopic deposit formation on polycrystalline gold by lithographic printing and writing of 1,2-dioleoyl-sn-glycero-3-phosphocholine and eicosanethiol mixtures, with the latter compound being a model case for self-assembled monolayers (SAMs). By analyzing the ink transport rates, we found that the transfer of thiols was fully controlled by the fluid lipid matrix allowing to achieve a certain jetting regime, i.e., transport rates previously not reported in dip-pen nanolithography (DPN) studies on surface-reactive, SAM-forming molecules. Such a transport behavior deviated significantly from the so-called molecular diffusion models, and it was most obvious at the high writing speeds, close to 100 µm s-1. Moreover, the combined data from imaging ellipsometry, scanning electron microscopy, atomic force microscopy (AFM), and spectroscopy revealed a rapid and efficient ink phase separation occurring in the AFM tip-gold contact zone. The force curve analysis indicated formation of a mixed ink meniscus behaving as a self-organizing liquid. Based on our data, it has to be considered as one of the co-acting mechanisms driving the surface reactions and self-assembly under such highly nonequilibrium, crowded environment conditions. The results of the present study significantly extend the capabilities of DPN using standard AFM instrumentation: in the writing regime, the patterning speed was already comparable to that achievable by using electron beam systems. We demonstrate that lipid flow-controlled chemical patterning process is directly applicable for rapid prototyping of solid-state devices having mesoscopic features as well as for biomolecular architectures.


Assuntos
Ouro/química , Tinta , Modelos Químicos , Fosfolipídeos/química , Impressão , Redação , Compostos de Sulfidrila/química
20.
Biomater Sci ; 7(8): 3497-3509, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31290861

RESUMO

An array of biological properties is demonstrated in the category of extracts broadly known as ulvans, including antibacterial, anti-inflammatory and anti-coagulant activities. However, the development of this category in biomedical applications is limited due to high structural variability across species and a lack of consistent and scalable sources. In addition, the modification and formulation of these molecules is still in its infancy with regard to progressing to product development. Here, a sulfated and rhamnose-rich, xylorhamno-uronic acid (XRU) extract from the cell wall of a controlled source of cultivated Australian ulvacean macroalgae resembles mammalian connective glycosaminoglycans. It is therefore a strong candidate for applications in wound healing and tissue regeneration. This study targets the development of polysaccharide modification for fabrication of 3D scaffolds for skin cell (fibroblast) culture. The XRU extract is methacrylated and UV-crosslinked to produce hydrogels with tuneable mechanical properties. The hydrogels demonstrate high cell viability and support cell proliferation over 14 days, which are far more functional than comparable alginate gels. Importantly, an XRU-based bioink is developed for extrusion printing 3D constructs both with and without cell encapsulation. These results highlight the close to product potential of this rhamnose-rich XRU extract as a promising biomaterial toward wound healing. Future studies should be focused on in-depth in vitro characterizations to examine the role of the material in dermal extracellular matrix (ECM) secretion of 3D printed structures, and in vivo characterizations to assess its capacity in supporting wound healing.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Hidrogéis/química , Ramnose/química , Sulfatos/química , Ácidos Urônicos/química , Cicatrização/efeitos dos fármacos , Fenômenos Químicos , Humanos , Impressão , Pele/citologia , Água/química
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