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1.
Nano Today ; 25: 156, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31186673

RESUMO

[This corrects the article PMC5016035.].

4.
Adv Mater ; 31(10): e1806899, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663123

RESUMO

The development of 3D in vitro models capable of recapitulating native tumor microenvironments could improve the translatability of potential anticancer drugs and treatments. Here, 3D bioprinting techniques are used to build tumor constructs via precise placement of living cells, functional biomaterials, and programmable release capsules. This enables the spatiotemporal control of signaling molecular gradients, thereby dynamically modulating cellular behaviors at a local level. Vascularized tumor models are created to mimic key steps of cancer dissemination (invasion, intravasation, and angiogenesis), based on guided migration of tumor cells and endothelial cells in the context of stromal cells and growth factors. The utility of the metastatic models for drug screening is demonstrated by evaluating the anticancer efficacy of immunotoxins. These 3D vascularized tumor tissues provide a proof-of-concept platform to i) fundamentally explore the molecular mechanisms of tumor progression and metastasis, and ii) preclinically identify therapeutic agents and screen anticancer drugs.


Assuntos
Biomimética , Neoplasias , Impressão Tridimensional , Engenharia Tecidual , Microambiente Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Humanos , Neoplasias/patologia , Tecidos Suporte/química
5.
Adv Mater ; : e1803980, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30151842

RESUMO

Extrusion-based 3D printing, an emerging technology, has been previously used in the comprehensive fabrication of light-emitting diodes using various functional inks, without cleanrooms or conventional microfabrication techniques. Here, polymer-based photodetectors exhibiting high performance are fully 3D printed and thoroughly characterized. A semiconducting polymer ink is printed and optimized for the active layer of the photodetector, achieving an external quantum efficiency of 25.3%, which is comparable to that of microfabricated counterparts and yet created solely via a one-pot custom built 3D-printing tool housed under ambient conditions. The devices are integrated into image sensing arrays with high sensitivity and wide field of view, by 3D printing interconnected photodetectors directly on flexible substrates and hemispherical surfaces. This approach is further extended to create integrated multifunctional devices consisting of optically coupled photodetectors and light-emitting diodes, demonstrating for the first time the multifunctional integration of multiple semiconducting device types which are fully 3D printed on a single platform. The 3D-printed optoelectronic devices are made without conventional microfabrication facilities, allowing for flexibility in the design and manufacturing of next-generation wearable and 3D-structured optoelectronics, and validating the potential of 3D printing to achieve high-performance integrated active electronic materials and devices.

6.
Adv Mater ; 30(23): e1707495, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29691902

RESUMO

Conventional 3D printing technologies typically rely on open-loop, calibrate-then-print operation procedures. An alternative approach is adaptive 3D printing, which is a closed-loop method that combines real-time feedback control and direct ink writing of functional materials in order to fabricate devices on moving freeform surfaces. Here, it is demonstrated that the changes of states in the 3D printing workspace in terms of the geometries and motions of target surfaces can be perceived by an integrated robotic system aided by computer vision. A hybrid fabrication procedure combining 3D printing of electrical connects with automatic pick-and-placing of surface-mounted electronic components yields functional electronic devices on a free-moving human hand. Using this same approach, cell-laden hydrogels are also printed on live mice, creating a model for future studies of wound-healing diseases. This adaptive 3D printing method may lead to new forms of smart manufacturing technologies for directly printed wearable devices on the body and for advanced medical treatments.


Assuntos
Impressão Tridimensional , Animais , Humanos , Hidrogéis , Camundongos
7.
Adv Mater Technol ; 3(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29608202

RESUMO

The design and development of novel methodologies and customized materials to fabricate patient-specific 3D printed organ models with integrated sensing capabilities could yield advances in smart surgical aids for preoperative planning and rehearsal. Here, we demonstrate 3D printed prostate models with physical properties of tissue and integrated soft electronic sensors using custom-formulated polymeric inks. The models show high quantitative fidelity in static and dynamic mechanical properties, optical characteristics, and anatomical geometries to patient tissues and organs. The models offer tissue-mimicking tactile sensation and behavior and thus can be used for the prediction of organ physical behavior under deformation. The prediction results show good agreement with values obtained from simulations. The models also allow the application of surgical and diagnostic tools to their surface and inner channels. Finally, via the conformal integration of 3D printed soft electronic sensors, pressure applied to the models with surgical tools can be quantitatively measured.

8.
Annu Rev Anal Chem (Palo Alto Calif) ; 11(1): 287-306, 2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29589961

RESUMO

Medical errors are a major concern in clinical practice, suggesting the need for advanced surgical aids for preoperative planning and rehearsal. Conventionally, CT and MRI scans, as well as 3D visualization techniques, have been utilized as the primary tools for surgical planning. While effective, it would be useful if additional aids could be developed and utilized in particularly complex procedures involving unusual anatomical abnormalities that could benefit from tangible objects providing spatial sense, anatomical accuracy, and tactile feedback. Recent advancements in 3D printing technologies have facilitated the creation of patient-specific organ models with the purpose of providing an effective solution for preoperative planning, rehearsal, and spatiotemporal mapping. Here, we review the state-of-the-art in 3D printed, patient-specific organ models with an emphasis on 3D printing material systems, integrated functionalities, and their corresponding surgical applications and implications. Prior limitations, current progress, and future perspectives in this important area are also broadly discussed.


Assuntos
Cirurgia Geral/métodos , Modelos Anatômicos , Impressão Tridimensional , Humanos , Imagem por Ressonância Magnética , Tomografia Computadorizada por Raios X
9.
Nano Lett ; 17(12): 7207-7212, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29120648

RESUMO

Rapid, simple, and cost-effective diagnostics are needed to improve healthcare at the point of care (POC). However, the most widely used POC diagnostic, the lateral flow immunoassay (LFA), is ∼1000-times less sensitive and has a smaller analytical range than laboratory tests, requiring a confirmatory test to establish truly negative results. Here, a rational and systematic strategy is used to design the LFA contrast label (i.e., gold nanoparticles) to improve the analytical sensitivity, analytical detection range, and antigen quantification of LFAs. Specifically, we discovered that the size (30, 60, or 100 nm) of the gold nanoparticles is a main contributor to the LFA analytical performance through both the degree of receptor interaction and the ultimate visual or thermal contrast signals. Using the optimal LFA design, we demonstrated the ability to improve the analytical sensitivity by 256-fold and expand the analytical detection range from 3 log10 to 6 log10 for diagnosing patients with inflammatory conditions by measuring C-reactive protein. This work demonstrates that, with appropriate design of the contrast label, a simple and commonly used diagnostic technology can compete with more expensive state-of-the-art laboratory tests.


Assuntos
Ouro/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Anticorpos/imunologia , Proteína C-Reativa/análise , Proteína C-Reativa/imunologia , Difusão , Humanos , Inflamação/diagnóstico , Cinética , Limite de Detecção , Tamanho da Partícula , Testes Imediatos , Temperatura Ambiente
10.
Adv Mater ; 29(27)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28474793

RESUMO

The development of methods for the 3D printing of multifunctional devices could impact areas ranging from wearable electronics and energy harvesting devices to smart prosthetics and human-machine interfaces. Recently, the development of stretchable electronic devices has accelerated, concomitant with advances in functional materials and fabrication processes. In particular, novel strategies have been developed to enable the intimate biointegration of wearable electronic devices with human skin in ways that bypass the mechanical and thermal restrictions of traditional microfabrication technologies. Here, a multimaterial, multiscale, and multifunctional 3D printing approach is employed to fabricate 3D tactile sensors under ambient conditions conformally onto freeform surfaces. The customized sensor is demonstrated with the capabilities of detecting and differentiating human movements, including pulse monitoring and finger motions. The custom 3D printing of functional materials and devices opens new routes for the biointegration of various sensors in wearable electronics systems, and toward advanced bionic skin applications.


Assuntos
Impressão Tridimensional , Monitorização Fisiológica
11.
Nat Biomed Eng ; 1(10): 775-776, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31015595
12.
Biointerphases ; 11(4): 041003, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27814665

RESUMO

Recognition and manipulation of graphene edges enable the control of physical properties of graphene-based devices. Recently, the authors have identified a peptide that preferentially binds to graphene edges from a combinatorial peptide library. In this study, the authors examine the functional basis for the edge binding peptide using experimental and computational methods. The effect of amino acid substitution, sequence context, and solution pH value on the binding of the peptide to graphene has been investigated. The N-terminus glutamic acid residue plays a key role in recognizing and binding to graphene edges. The protonation, substitution, and positional context of the glutamic acid residue impact graphene edge-binding. Our findings provide insights into the binding mechanisms and the design of peptides for recognizing and functionalizing graphene edges.


Assuntos
Grafite/metabolismo , Peptídeos/metabolismo , Propriedades de Superfície , Substituição de Aminoácidos , Biologia Computacional , Ácido Glutâmico/genética , Ácido Glutâmico/metabolismo , Concentração de Íons de Hidrogênio , Peptídeos/genética , Ligação Proteica
13.
Nano Today ; 11(3): 330-350, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27617026

RESUMO

The ability to three-dimensionally interweave biological and functional materials could enable the creation of bionic devices possessing unique and compelling geometries, properties, and functionalities. Indeed, interfacing high performance active devices with biology could impact a variety of fields, including regenerative bioelectronic medicines, smart prosthetics, medical robotics, and human-machine interfaces. Biology, from the molecular scale of DNA and proteins, to the macroscopic scale of tissues and organs, is three-dimensional, often soft and stretchable, and temperature sensitive. This renders most biological platforms incompatible with the fabrication and materials processing methods that have been developed and optimized for functional electronics, which are typically planar, rigid and brittle. A number of strategies have been developed to overcome these dichotomies. One particularly novel approach is the use of extrusion-based multi-material 3D printing, which is an additive manufacturing technology that offers a freeform fabrication strategy. This approach addresses the dichotomies presented above by (1) using 3D printing and imaging for customized, hierarchical, and interwoven device architectures; (2) employing nanotechnology as an enabling route for introducing high performance materials, with the potential for exhibiting properties not found in the bulk; and (3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. Further, 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This blending of 3D printing, novel nanomaterial properties, and 'living' platforms may enable next-generation bionic systems. In this review, we highlight this synergistic integration of the unique properties of nanomaterials with the versatility of extrusion-based 3D printing technologies to interweave nanomaterials and fabricate novel bionic devices.

14.
Lab Chip ; 16(10): 1946, 2016 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-27090610

RESUMO

Correction for '3D printed nervous system on a chip' by Blake N. Johnson et al., Lab Chip, 2016, 16, 1393-1400.

15.
Lab Chip ; 16(8): 1393-400, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26669842

RESUMO

Bioinspired organ-level in vitro platforms are emerging as effective technologies for fundamental research, drug discovery, and personalized healthcare. In particular, models for nervous system research are especially important, due to the complexity of neurological phenomena and challenges associated with developing targeted treatment of neurological disorders. Here we introduce an additive manufacturing-based approach in the form of a bioinspired, customizable 3D printed nervous system on a chip (3DNSC) for the study of viral infection in the nervous system. Micro-extrusion 3D printing strategies enabled the assembly of biomimetic scaffold components (microchannels and compartmented chambers) for the alignment of axonal networks and spatial organization of cellular components. Physiologically relevant studies of nervous system infection using the multiscale biomimetic device demonstrated the functionality of the in vitro platform. We found that Schwann cells participate in axon-to-cell viral spread but appear refractory to infection, exhibiting a multiplicity of infection (MOI) of 1.4 genomes per cell. These results suggest that 3D printing is a valuable approach for the prototyping of a customized model nervous system on a chip technology.


Assuntos
Biomimética/instrumentação , Dispositivos Lab-On-A-Chip , Sistema Nervoso , Impressão Tridimensional/instrumentação , Animais , Sistema Nervoso/citologia , Sistema Nervoso/virologia , Ratos
16.
Nano Lett ; 15(8): 5321-9, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26042472

RESUMO

The development of methods for achieving precise spatiotemporal control over chemical and biomolecular gradients could enable significant advances in areas such as synthetic tissue engineering, biotic-abiotic interfaces, and bionanotechnology. Living organisms guide tissue development through highly orchestrated gradients of biomolecules that direct cell growth, migration, and differentiation. While numerous methods have been developed to manipulate and implement biomolecular gradients, integrating gradients into multiplexed, three-dimensional (3D) matrices remains a critical challenge. Here we present a method to 3D print stimuli-responsive core/shell capsules for programmable release of multiplexed gradients within hydrogel matrices. These capsules are composed of an aqueous core, which can be formulated to maintain the activity of payload biomolecules, and a poly(lactic-co-glycolic) acid (PLGA, an FDA approved polymer) shell. Importantly, the shell can be loaded with plasmonic gold nanorods (AuNRs), which permits selective rupturing of the capsule when irradiated with a laser wavelength specifically determined by the lengths of the nanorods. This precise control over space, time, and selectivity allows for the ability to pattern 2D and 3D multiplexed arrays of enzyme-loaded capsules along with tunable laser-triggered rupture and release of active enzymes into a hydrogel ambient. The advantages of this 3D printing-based method include (1) highly monodisperse capsules, (2) efficient encapsulation of biomolecular payloads, (3) precise spatial patterning of capsule arrays, (4) "on the fly" programmable reconfiguration of gradients, and (5) versatility for incorporation in hierarchical architectures. Indeed, 3D printing of programmable release capsules may represent a powerful new tool to enable spatiotemporal control over biomolecular gradients.


Assuntos
Preparações de Ação Retardada/química , Ouro/química , Ácido Láctico/química , Nanotubos/química , Ácido Poliglicólico/química , Impressão Tridimensional , Cápsulas/química , Nanotubos/ultraestrutura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
17.
Adv Funct Mater ; 25(39): 6205-6217, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26924958

RESUMO

An imaging-coupled 3D printing methodology for the design, optimization, and fabrication of a customized nerve repair technology for complex injuries is presented. The custom scaffolds are deterministically fabricated via a microextrusion printing principle which enables the simultaneous incorporation of anatomical geometries, biomimetic physical cues, and spatially controlled biochemical gradients in a one-pot 3D manufacturing approach.

18.
Nano Lett ; 14(12): 7017-23, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25360485

RESUMO

Developing the ability to 3D print various classes of materials possessing distinct properties could enable the freeform generation of active electronics in unique functional, interwoven architectures. Achieving seamless integration of diverse materials with 3D printing is a significant challenge that requires overcoming discrepancies in material properties in addition to ensuring that all the materials are compatible with the 3D printing process. To date, 3D printing has been limited to specific plastics, passive conductors, and a few biological materials. Here, we show that diverse classes of materials can be 3D printed and fully integrated into device components with active properties. Specifically, we demonstrate the seamless interweaving of five different materials, including (1) emissive semiconducting inorganic nanoparticles, (2) an elastomeric matrix, (3) organic polymers as charge transport layers, (4) solid and liquid metal leads, and (5) a UV-adhesive transparent substrate layer. As a proof of concept for demonstrating the integrated functionality of these materials, we 3D printed quantum dot-based light-emitting diodes (QD-LEDs) that exhibit pure and tunable color emission properties. By further incorporating the 3D scanning of surface topologies, we demonstrate the ability to conformally print devices onto curvilinear surfaces, such as contact lenses. Finally, we show that novel architectures that are not easily accessed using standard microfabrication techniques can be constructed, by 3D printing a 2 × 2 × 2 cube of encapsulated LEDs, in which every component of the cube and electronics are 3D printed. Overall, these results suggest that 3D printing is more versatile than has been demonstrated to date and is capable of integrating many distinct classes of materials.

19.
Nano Lett ; 13(12): 6197-202, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24274657

RESUMO

Piezoelectric nanowires are an important class of smart materials for next-generation applications including energy harvesting, robotic actuation, and bioMEMS. Lead zirconate titanate (PZT), in particular, has attracted significant attention, owing to its superior electromechanical conversion performance. Yet, the ability to synthesize crystalline PZT nanowires with well-controlled properties remains a challenge. Applications of common nanosynthesis methods to PZT are hampered by issues such as slow kinetics, lack of suitable catalysts, and harsh reaction conditions. Here we report a versatile biomimetic method, in which biotemplates are used to define PZT nanostructures, allowing for rational control over composition and crystallinity. Specifically, stoichiometric PZT nanowires were synthesized using both polysaccharide (alginate) and bacteriophage templates. The wires possessed measured piezoelectric constants of up to 132 pm/V after poling, among the highest reported for PZT nanomaterials. Further, integrated devices can generate up to 0.820 µW/cm(2) of power. These results suggest that biotemplated piezoelectric nanowires are attractive candidates for stimuli-responsive nanosensors, adaptive nanoactuators, and nanoscale energy harvesters.


Assuntos
Chumbo/química , Sistemas Microeletromecânicos , Nanofios/química , Titânio/química , Zircônio/química , Bacteriófagos/química , Fontes de Energia Bioelétrica , Nanoestruturas/química , Polissacarídeos/química
20.
Lab Chip ; 13(18): 3735-40, 2013 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23884453

RESUMO

The generation of an effective method for stimulating neuronal growth in specific directions, along well-defined geometries, and in numerous cells could impact areas ranging from fundamental studies of neuronal evolution and morphogenesis, to applications in biomedical diagnostics and nerve regeneration. Applied mechanical stress can regulate neurite growth. Indeed, previous studies have shown that neuronal cells can develop and extend neurites with rapid growth rates under applied "towing" tensions imparted by micropipettes. Yet, such methods are complex and exhibit low throughputs, as the tension is applied serially to individual cells. Here we present a novel approach to inducing neurite growth in multiple cells in parallel, by using a miniaturized platform with numerous microchannels. Upon connection of a vacuum to these microchannels, tension can be applied on multiple cells simultaneously to induce the growth of neurites. A theoretical model was also developed to understand the effect of tension on the dynamics of neurite development.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Estresse Mecânico , Animais , Anticorpos/imunologia , Dimetilpolisiloxanos/química , Vidro/química , Imunoensaio , Miniaturização , Modelos Teóricos , Neuritos/fisiologia , Neurônios/citologia , Neurônios/metabolismo , Células PC12 , Ratos , Proteínas tau/imunologia
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