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1.
Langmuir ; 34(15): 4651-4657, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29554798

RESUMEN

An electrically induced bottom-up process was introduced for the fabrication of multifunctional nanostructures of polymers. Without requiring complicated photolithography or printing techniques, the fabrication process first produced a conducting template by colloidal lithography to create an interconnected conduction pathway. By supplying an electrical charge to the conducting network, the conducting areas were enabled with a highly energized surface that generally deactivated the adsorbed reactive species and inhibited the vapor deposition of poly- p-xylylene polymers. However, the template allowed the deposition of ordered poly- p-xylylene nanostructures only on the confined and negative areas of the conducting template, in a relatively large centimeter-scale production. The wide selection of functionality and multifunctional capability of poly- p-xylylenes naturally rendered the synergistic and orthogonal chemical reactivity of the resulting nanostructures. With only a few steps, the construction of a nanometer topology with the functionalization of multiple chemical conducts can be achieved, and the selected deposition process represents a state-of-the-art nanostructure fabrication in a simple and versatile approach from the bottom up.

2.
Langmuir ; 33(51): 14657-14662, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29191017

RESUMEN

Antifouling surfaces that are resistant to protein adsorption and cell adhesion are desirable for many biomedical devices, such as diagnostic devices, biosensors, and implants. In this study, we developed an antifouling hyperbranched polyglycerol (hPG) surface on hydroxyl poly-p-xylylene (PPX-OH). PPX-OH was deposited via chemical vapor deposition (CVD), and an hPG film was then developed via the ring-opening reaction of glycidol. The hPG film greatly reduced the adhesion of L929 cells and platelets as well as protein adsorption. The addition of alkenyl groups in the hPG layer allows the conjugation of biomolecules, such as peptides and biotin, and elicits specific biological interactions. Since the CVD deposition of PPX-OH could be applied to most types of materials, our approach makes it possible to decorate an antifouling hPG film on most types of materials. Our method could be applied to biosensors, diagnostics, and biomedical devices in the future.

3.
Langmuir ; 33(36): 8943-8949, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28825482

RESUMEN

In addition to the widely adopted method of controlling cell attachment for cell patterning, pattern formation via cell proliferation and differentiation is demonstrated using precisely defined interface chemistry and spatial topology. The interface platform is created using a maleimide-functionalized parylene coating (maleimide-PPX) that provides two routes for controlled conjugation accessibility, including the maleimide-thiol coupling reaction and the thiol-ene click reaction, with a high reaction specificity under mild conditions. The coating technology is a prime tool for the immobilization of sensitive molecules, such as growth factor proteins. Conjugation of fibroblast growth factor 2 (FGF-2) and bone morphogenetic protein (BMP-2) was performed on the coating surface by elegantly manipulating the reaction routes, and confining the conjugation reaction to selected areas was accomplished using microcontact printing (µCP) and/or UV irradiation photopatterning. The modified interface provides chemically and topologically defined signals that are recognized by cultured murine preosteoblast cells for proliferation (by FGF-2) and osteogenesis (by BMP-2) activities in specific locations. The reported technique additionally enabled synergistic pattern formation for both osteogenesis and proliferation activities on the same interface, which is difficult to perform using conventional cell attachment patterns. Because of the versatility of the coating, which can be applied to a wide range of materials and on curved and complex devices, the proposed technology is extendable to other prospective biomaterial designs and material interface modifications.


Asunto(s)
Diferenciación Celular , Animales , Materiales Biocompatibles , Ratones , Osteogénesis , Polímeros , Estudios Prospectivos
4.
Langmuir ; 30(47): 14257-62, 2014 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-25377994

RESUMEN

A surface that resists protein adsorption and cell adhesion is highly desirable for many biomedical applications such as blood-contact devices and biosensors. In this study, we fabricated a carboxybetaine-containing surface and evaluated its antifouling efficacy. First, an amine-containing substrate was created by chemical vapor deposition of 4-aminomethyl-p-xylylene-co-p-xylylene (Amino-PPX). Aldehyde-ended carboxybetaine molecules were synthesized and conjugated onto Amino-PPX. The carboxybetaine-PPX surface greatly reduced protein adsorption and cell adhesion. The attachment of L929 cells on the carboxybetaine-PPX surface was reduced by 87% compared to the cell adhesion on Amino-PPX. Furthermore, RGD peptides could be conjugated on carboxybetaine-PPX to mediate specific cell adhesion. In conclusion, we demonstrate that a surface decoration with monocarboxybetaine molecules is useful for antifouling applications.


Asunto(s)
Compuestos de Anilina/química , Betaína/química , Polímeros/química , Proteínas/química , Adsorción , Adhesión Celular/efectos de los fármacos , Propiedades de Superficie
5.
ACS Sens ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982801

RESUMEN

Celiac patients are required to strictly adhere to a gluten-free diet because even trace amounts of gluten can damage their small intestine and leading to serious complications. Despite increased awareness, gluten can still be present in products due to cross-contamination or hidden ingredients, making regular monitoring essential. With the goal of guaranteeing food safety for consuming labeled gluten-free products, a capacitive aptasensor was constructed to target gliadin, the main allergic gluten protein for celiac disease. The success of capacitive aptasensing was primarily realized by coating a Parylene double-layer (1000 nm Parylene C at the bottom with 400 nm Parylene AM on top) on the electrode surface to ensure both high insulation quality and abundant reactive amino functionalities. Under the optimal concentration of aptamer (5 µM) used for immobilization, a strong linear relationship exists between the amount of gliadin (0.01-1.0 mg/mL) and the corresponding ΔC response (total capacitance decrease during a 20 min monitoring period after sample introduction), with an R2 of 0.9843. The detection limit is 0.007 mg/mL (S/N > 5), equivalent to 0.014 mg/mL (14 ppm) of gluten content. Spike recovery tests identified this system is free from interferences in corn and cassava flour matrices. The analytical results of 24 commercial wheat flour samples correlated well with a gliadin ELISA assay (R2 = 0.9754). The proposed label-free and reagentless capacitive aptasensor offers advantages of simplicity, cost-effectiveness, ease of production, and speediness, making it a promising tool for verifying products labeled as gluten-free (gluten content <20 ppm).

6.
RSC Adv ; 14(19): 12966-12976, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38655476

RESUMEN

Surface coating technology is broadly demanded across various fields, including marine and biomedical materials; therefore, a facile and versatile approach is desired. This study proposed an attractive surface coating strategy using photo-crosslinkable benzophenone (BP) moiety for biomaterials application. BP-containing "bioglue" polymer can effectively crosslink with all kinds of surfaces and biomolecules. Upon exposure to ultraviolet (UV) light, free radical reaction from the BP glue facilitates the immobilization of diverse molecules onto different substrates in a straightforward and user-friendly manner. Through either one-step, mixing the bioglue with targeted biomolecules, or two-step methods, pre-coating the bioglue and then adding targeted biomolecules, polyacrylic acid (PAA), cyclic RGD-containing peptides, and proteins (gelatin, collagen, and fibronectin) were successfully immobilized on substrates. After drying the bioglue, targeted biomolecules can still be immobilized on the surfaces preserving their bioactivity. Cell culture on biomolecule-immobilized surfaces using NIH 3T3 fibroblasts and human bone marrow stem cells (hBMSCs) showed significant improvement of cell adhesion and activity compared to the unmodified control in serum-free media after 24 hours. Furthermore, hBMSCs on the fibronectin-immobilized surface showed an increased calcium deposition after 21 days of osteogenic differentiation, suggesting that the immobilized fibronectin is highly bioactive. Given the straightforward protocol and substrate-independent bioglue, the proposed coating strategy is promising in broad-range fields.

7.
ACS Appl Mater Interfaces ; 15(41): 48754-48763, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37793161

RESUMEN

The superhydrophobic properties of material surfaces have attracted significant research and practical development in a wide range of applications. In the present study, a superhydrophobic coating was fabricated using a vapor-phase sublimation and deposition process. This process offers several advantages, including a controllable and tunable superhydrophobic property, a dry and solvent-free process that uses well-defined water/ice templates during fabrication, and a coating technology that is applicable to various substrates, regardless of their dimensions or complex geometric configurations. The fabrication process exploits time-dependent condensation to produce ice templates with a controlled surface morphology and roughness. The templates are sacrificed via vapor sublimation, which results in mass transfer of water vapor out of the system. A second vapor source of a polymer precursor is then introduced to the system, and deposition occurs upon polymerization on the iced templates, replicating the same topologies from the iced templates. The continuation of the co-current sublimation and deposition processes finally renders permanent hierarchical structures of the polymer coatings that combine the native hydrophobic property of the polymer and the structured property by the sacrificed ice templates, achieving a level of superhydrophobicity that is tunable from 90° to 164°. The experiments demonstrated the use of [2,2]paracyclophanes as the starting materials for forming the superhydrophobic coatings of poly(p-xylylenes) on substrate surfaces. In comparison to conventional vapor deposition of poly(p-xylylenes), which resulted in dense thin-film coatings with only a moderate water contact angle of approximately 90°, the reported superhydrophobic coatings and fabrication process can achieve a high water contact angle of 164°. Demonstrations furthermore revealed that the proposed coatings are durable while maintaining superhydrophobicity on various substrates, including an intraocular lens and a cardiovascular stent, even against harsh treatment conditions and varied solution compositions used on the substrates.

8.
Langmuir ; 28(40): 14313-22, 2012 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-22966949

RESUMEN

Poly(4-benzoyl-p-xylylene-co-p-xylylene), a biologically compatible photoreactive polymer belonging to the parylene family, can be deposited using a chemical vapor deposition (CVD) polymerization process on a wide range of substrates. This study discovered that the solvent stability of poly(4-benzoyl-p-xylylene-co-p-xylylene) in acetone is significantly increased when exposed to approximately 365 nm of UV irradiation, because of the cross-linking of benzophenone side chains with adjacent molecules. This discovery makes the photodefinable polymer a powerful tool for use as a negative photoresist for surface microstructuring and biointerface engineering purposes. The polymer is extensively characterized using infrared reflection adsorption spectroscopy (IRRAS), scanning electron microscopy (SEM), and imaging ellipsometry. Furthermore, the vapor-based polymer coating process provides access to substrates with unconventional and complex three-dimensional (3D) geometries, as compared to conventional spin-coated resists that are limited to flat 2D assemblies. Moreover, this photoresist technology is seamlessly integrated with other functionalized parylenes including aldehyde-, acetylene-, and amine-functionalized parylenes to create unique surface microstructures that are chemically and topographically defined. The photopatterning and immobilization protocols described in this paper represent an approach that avoids contact between harmful substances (such as solvents and irradiations) and sensitive biomolecules. Finally, multiple biomolecules on planar substrates, as well as on unconventional 3D substrates (e.g., stents), are presented.


Asunto(s)
Procesos Fotoquímicos , Polímeros/química , Xilenos/química , Modelos Moleculares , Conformación Molecular , Polimerizacion , Volatilización
9.
Macromol Rapid Commun ; 33(10): 922-7, 2012 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-22351376

RESUMEN

Reactive polymer coatings were synthesized via chemical vapor deposition (CVD) polymerization process. These coatings decouple surface design from bulk properties of underlying materials and provide a facile and general route to support thiol-ene and thiol-yne reactions on a variety of substrate materials. Through the reported technique, surface functions can be activated through a simple design of thiol-terminated molecules such as polyethylene glycols (PEGs) or peptides (GRGDYC), and the according biological functions were demonstrated in controlled and low-fouling protein adsorptions as well as accurately manipulated cell attachments.


Asunto(s)
Polímeros/química , Compuestos de Sulfhidrilo/química , Alquenos/química , Alquinos/química , Secuencia de Aminoácidos , Química Clic , Fibrinógeno/química , Gases/química , Polimerizacion , Compuestos de Quinolinio/química , Propiedades de Superficie
10.
Polymers (Basel) ; 14(2)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35054631

RESUMEN

A facial, versatile, and universal method that breaks the substrate limits is desirable for antifouling treatment. Thin films of functional poly-p-xylylenes (PPX) that are deposited using chemical vapor deposition (CVD) provide a powerful platform for surface immobilization of molecules. In this study, we prepared an alkyne-functionalized PPX coating on which poly (sulfobetaine methacrylate-co-Az) could be conjugated via click chemistry. We found that the conjugated polymers were very stable and inhibited cell adhesion and protein adsorption effectively. The same conjugation strategy could also be applied to conjugate azide-containing poly (ethylene glycol) and poly (NIPAAm). The results indicate that our method provides a simple and robust tool for fabricating antifouling surfaces on a wide range of substrates using CVD technology of functionalized poly (p-xylylenes) for biosensor, diagnostics, immunoassay, and other biomaterial applications.

11.
Mater Today Bio ; 13: 100213, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35198961

RESUMEN

Tissue engineering based on the combined use of isolated cells, scaffolds, and growth factors is widely used; however, the manufacture of cell-preloaded scaffolds faces challenges. Herein, we fabricated a multicomponent scaffold with multiple component accommodations, including bioactive molecules (BMs), such as fibroblast growth factor-2 (FGF-2) and l-ascorbic acid 2-phosphate (A2-P), and living cells of human adipose-derived stem cells (hASCs), within one scaffold construct. We report an innovative fabrication process based on vapor-phased construction using iced templates for vapor sublimation. Simultaneously, the vaporized water molecules were replaced by vapor deposition of poly-p-xylylene (PPX, USP Class VI, highly compatible polymer, FDA-approved records), forming a three-dimensional and porous scaffold matrix. More importantly, a multicomponent modification was achieved based on using nonvolatile solutes, including bioactive molecules of FGF-2 and A2-P, and living cells of hASCs, to prepare iced templates for sublimation. Additionally, the fabrication and construction resulted in a multicomponent scaffold product comprising the devised molecules, cells, and vapor-polymerized poly-p-xylylene as the scaffold matrix. The clean and dry fabrication process did not require catalysts, initiators or plasticizers, and potentially harmful solvents, and the scaffold products were produced in simple steps within hours of the processing time. Cell viability analysis showed a high survival rate (approximately 86.4%) for the accommodated hASCs in the fabricated scaffold product, and a surprising multilineage differentiation potential of hASCs was highly upregulated because of synergistic guidance by the same accommodated FGF-2 and A2-P components. Proliferation and self-renewal activities were also demonstrated with enhancement of the multicomponent scaffold product. Finally, in vivo calvarial defect studies further revealed that the constructed scaffolds provided blood vessels to grow into the bone defect areas with enhancement, and the induced conduction of osteoblast growth also promoted bone healing toward osseointegration. The reported scaffold construction technology represents a prospective tissue engineering scaffold product to enable accommodable and customizable versatility to control the distribution and composition of loading delicate BMs and living hASCs in one scaffold construct and demonstrates unlimited applications in tissue engineering repair and regenerative medicine applications.

12.
Mater Today Bio ; 16: 100403, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36090608

RESUMEN

A multicomponent vapour-deposited porous (MVP) coating with combined physical and biochemical properties was fabricated based on a chemical vapour sublimation and deposition process. Multiple components are used based on their natural thermodynamic properties, being volatile and/or nonvolatile, resulting in the sublimation of water vapour (from an iced template), and a simultaneous deposition process of poly-p-xylylene occurs upon radical polymerization into a disordered structure, forming porous coatings of MVP on various substrates. In terms of physical properties, the coating technology exhibits adjustable hydrophobicity by tuning the surface morphology by timed control of the sublimation of the iced template layer from a substrate. However, by using a nonvolatile solution during fabrication, an impregnation process of the deposited poly-p-xylylene on such a solution with tuning contact angles produces an MVP coating with a customizable elastic modulus based on deformation-elasticity theory. Moreover, patterning physical structures with adjustable pore size and/or porosity of the coatings, as well as modulation and compartmentalization to introduce necessary boundaries of microstructures within one MVP coating layer, can be achieved during the proposed fabrication process. Finally, with a combination of defined solutions comprised of both volatile and nonvolatile multicomponents, including functional biomolecules, growth factor proteins, and living cells, the fabrication of the resultant MVP coating serves devised purposes exhibiting a variety of biological functions demonstrated with versatility for cell proliferation, osteogenesis, adipogenesis, odontogenesis, spheroid growth of stem cells, and a complex coculture system towards angiogenesis. Multicomponent porous coating technology is produced based on vapour sublimation and deposition upon radical polymerization that overturns conventional vapour-deposited coatings, resulting in only dense thin films, and in addition, the versatility of adjusting coating physical and chemical properties by exploiting the volatility mechanism of iced solution templates and accommodation of solute substances during the fabrication process. The MVP coating and the proposed fabrication technique represent a simple approach to provide a prospective interface coating layer for materials science and are attractive for unlimited applications.

13.
ACS Nano ; 2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36583476

RESUMEN

Direct neuronal reprogramming of somatic cells into induced neurons (iNs) has been recently established as a promising approach to generating neuron cells. Previous studies have reported that the biophysical cues of the in vitro microenvironment are potent modulators in the cell fate decision; thus, the present study explores the effects of a customized pattern (named colloidal self-assembled patterns, cSAPs) on iN generation from human fibroblasts using small molecules. The result revealed that the cSAP, composed of binary particles in a hexagonal-close-packed (hcp) geometry, is capable of improving neuronal reprogramming efficiency and steering the ratio of the iN subtypes. Cells exhibited distinct cell morphology, upregulated cell adhesion markers (i.e., SDC1 and ITGAV), enriched signaling pathways (i.e., Hippo and Wnt), and chromatin remodeling on the cSAP compared to those on the control substrates. The result also showed that the iN subtype specification on cSAP was surface-dependent; therefore, the defined physicochemical cue from each cSAP is exclusive. Our findings show that direct cell reprogramming can be manipulated through specific biophysical cues on the artificial matrix, which is significant in cell transdifferentiation and lineage conversion.

14.
Langmuir ; 27(1): 34-48, 2011 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-20590103

RESUMEN

Functionalized poly(p-xylylenes) constitute a versatile class of reactive polymers that can be prepared in a solventless process via chemical vapor deposition (CVD) polymerization. The resulting ultrathin coatings are typically pinhole-free and can be conformally deposited onto a wide range of substrates and materials. More importantly, appropriately selected functional groups can serve as anchoring sites for tailoring biointerface properties via the immobilization of biomolecules. In this article, controlled surface chemistries are outlined that use functionalized poly(p-xylylenes) as reactive coatings, including alkyne-functionalized coatings for Huisgen 1,3-dipolar cycloaddition reactions or aldehyde-functionalized coatings. The reactive coatings technology provides flexible access to a range of different surface chemistries, enabling a broad range of potential applications in microfluidics, medical device coatings, and biotechnology. In this feature article, we will highlight recent progress in vapor-based reactive coatings and will discuss potential benefits and current limitations.


Asunto(s)
Productos Biológicos/química , Polímeros/química , Xilenos/química , Microtecnología , Nanotecnología , Polimerizacion , Propiedades de Superficie , Volatilización
15.
Polymers (Basel) ; 13(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806497

RESUMEN

Conventional porous materials are mostly synthesized in solution-based methods involving solvents and initiators, and the functionalization of these porous materials usually requires additional and complex steps. In the current study, a methyl propiolate-functionalized porous poly-p-xylylene material was fabricated based on a unique vapor sublimation and deposition process. The process used a water solution and ice as the template with a customizable shape and dimensions, and the conventional chemical vapor deposition (CVD) polymerization of poly-p-xylylene on such an ice template formed a three-dimensional, porous poly-p-xylylene material with interconnected porous structures. More importantly, the functionality of methyl propiolate was well preserved by using methyl propiolate-substituted [2,2]-paracyclophane during the vapor deposition polymerization process and was installed in one step on the final porous poly-p-xylylene products. This functionality exhibited an intact structure and reactivity during the proposed vapor sublimation and deposition process and was proven to have no decomposition or side products after further characterization and conjugation experiments. The electron-withdrawing methyl propiolate group readily provided efficient alkynes as click azide-terminated molecules under copper-free and mild conditions at room temperature and in environmentally friendly solvents, such as water. The resulting methyl propiolate-functionalized porous poly-p-xylylene exhibited interface properties with clickable specific covalent attachment toward azide-terminated target molecules, which are widely available for drugs and biomolecules. The fabricated functional porous materials represent an advanced material featuring porous structures, a straightforward synthetic approach, and precise and controlled interface click chemistry, rendering long-term stability and efficacy to conjugate target functionalities that are expected to attract a variety of new applications.

16.
Nat Commun ; 12(1): 3413, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34099701

RESUMEN

Bottom-up approaches using building blocks of modules to fabricate scaffolds for tissue engineering applications have enabled the fabrication of structurally complex and multifunctional materials allowing for physical and chemical flexibility to better mimic the native extracellular matrix. Here we report a vapor-phased fabrication process for constructing three-dimensional modulated scaffold materials via simple steps based on controlling mass transport of vapor sublimation and deposition. We demonstrate the fabrication of scaffolds comprised of multiple biomolecules and living cells with built-in boundaries separating the distinct compartments containing defined biological configurations and functions. We show that the fabricated scaffolds have mass production potential. We demonstrate overall >80% cell viability of encapsulated cells and that modulated scaffolds exhibit enhanced cell proliferation, osteogenesis, and neurogenesis, which can be assembled into various geometric configurations. We perform cell co-culture experiments to show independent osteogenesis and angiogenesis activities from separate compartments in one scaffold construct.


Asunto(s)
Materiales Biomiméticos/química , Vapor , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Técnicas de Cultivo de Célula , Línea Celular , Proliferación Celular , Técnicas de Cocultivo , Matriz Extracelular , Humanos , Hidrogeles/química , Ratones , Neovascularización Fisiológica , Neurogénesis , Osteogénesis , Ratas
17.
J Am Chem Soc ; 132(51): 18023-5, 2010 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-21138264

RESUMEN

We report that nanostructuring via dip-pen nanolithography can be used for modification of a broad range of different substrates (polystyrene, Teflon, stainless steel, glass, silicon, rubber, etc.) without the need for reconfiguring the underlying printing technology. This is made possible through the use of vapor-based coatings that can be deposited on these substrates with excellent conformity, while providing functional groups for subsequent spatially directed click chemistry via dip-pen nanolithography. Pattern quality has been compared on six different substrates demonstrating that this approach indeed results in a surface modification protocol with potential use for a wide range of biotechnological applications.


Asunto(s)
Nanotecnología/métodos , Impresión/métodos , Xilenos/química , Química Clic , Propiedades de Superficie , Volatilización
18.
ACS Appl Bio Mater ; 3(9): 5678-5686, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-35021799

RESUMEN

In this study, a porous, three-dimensional material of parylene (poly-p-xylylene) incorporating keratin was fabricated. As an FDA-approved material, parylene is highly stable and biocompatible. Keratin is an abundant natural material that can enhance cell adhesion and wound healing. A unique vapor deposition construction technique dispersed keratin homogenously in the parylene system. Instead of using a conventional template, a sublimating template was applied. This composite porous scaffold was investigated mechanically and biologically. In addition, human adipose stem cells were cultured on the scaffold. The synergistic functions, including biocompatibility, permeability, cell adhesion, and stem cell differentiation, were investigated. A mouse excisional wound-healing model further verified that using the porous composite scaffold with stem cells accelerated the wound healing process, supporting its in vivo efficacy. The positive results demonstrated that this material has the potential to serve as a wound repair platform.

19.
ACS Biomater Sci Eng ; 6(4): 1836-1851, 2020 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33455323

RESUMEN

The surface properties of biomaterials are crucial at controlling biological interactions. Cells or tissues sense different stimuli from surfaces and respond accordingly. A number of studies have reported that fabricating complex stimuli-presenting surfaces is beneficial for mimicking and understanding the in vivo scenario where multi-physicochemical cues are present. Biological responses toward these surfaces could be either negative, such as immune responses, or positive, such as tissue regeneration. An ideal material surface should, therefore, be multifunctional, triggering the desired biological process and suppressing the unwanted side effects. The methods for material surface decoration can be very sophisticated, depending on the applications such as biosensors, medical devices, and/or implants. To date, decorating material surfaces with complex chemistries and topographies is still challenging, and methods are not straightforward. The majority of the methods require multiple steps and combinational approaches that include mask-based techniques, lithography, wet or dry etching, wet chemistry, or vapor-based coatings, among others. Although these methods have been established in the laboratory, easy-to-access and straightforward approaches need to be explored. This Review summarizes the state-of-the-art techniques for generating patterned multichemical and multitopographic signals on material surfaces, and the potential of having these surfaces in biointerface applications.


Asunto(s)
Materiales Biocompatibles , Técnicas Biosensibles , Prótesis e Implantes , Propiedades de Superficie
20.
Polymers (Basel) ; 13(1)2020 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-33374286

RESUMEN

A regulatable bioremediation capsule material was synthesized with isolated single-strain bacteria (Bacillus species, B. CMC1) and a regulator molecule (carboxymethyl cellulose, CMC) by a vapor-phased encapsulation method with simple steps of water sublimation and poly-p-xylylene deposition in chemical vapor deposition (CVD) process. Mechanically, the capsule construct exhibited a controllable shape and dimensions, and was composed of highly biocompatible poly-p-xylylene as the matrix with homogeneously distributed bacteria and CMC molecules. Versatility of the encapsulation of the molecules at the desired concentrations was achieved in the vapor-phased sublimation and deposition fabrication process. The discovery of the fabricated capsule revealed that viable living B. CMC1 inhabited the capsule, and the capsule enhanced bacterial growth due to the materials and process used. Biologically, the encapsulated B. CMC1 demonstrated viable and functional enzyme activity for cellulase activation, and such activity was regulatable and proportional to the concentration of the decorated CMC molecules in the same capsule construct. Impressively, 13% of cellulase activity increase was realized by encapsulation of B. CMC1 by poly-p-xylylene, and a further 34% of cellulase activity increase was achieved by encapsulation of additional 2.5% CMC. Accordingly, this synergistic effectiveness of the capsule constructs was established by combining enzymatic B. CMC1 bacteria and its regulatory CMC by poly-p-xylylene encapsulation process. This reported encapsulation process exhibited other advantages, including the use of simple steps and a dry and clean process free of harmful chemicals; most importantly, the process is scalable for mass production. The present study represents a novel method to fabricate bacteria-encapsulated capsule for cellulose degradation in bioremediation that can be used in various applications, such as wastewater treatment and transforming of cellulose into glucose for biofuel production. Moreover, the concept of this vapor-phased encapsulation technology can be correspondingly used to encapsulate multiple bacteria and regulators to enhance the specific enzyme functions for degradation of various organic matters.

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