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1.
Small ; 20(10): e2303966, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37907423

RESUMO

Multispectral/hyperspectral technologies can easily detect man-made objects in vegetation by subtle spectral differences between the object and vegetation, and powerful reconnaissance increases the demand for camouflage materials closely resembling vegetation spectra. However, previous biomimetic materials have only presented static colors that cannot change color, and camouflage in multiple bands is difficult to achieve. To address this challenge, inspiration is drawn from the color change of foliage, and a color-change model is proposed with active and static pigments embedded in a matrix medium. The color of a composite material is dominated by the colored active pigment, which conceals the color of the static pigments and the color is revealed when the active pigment fades. A color-changing biomimetic material (CCBM) is developed with a solution casting method by adopting microcapsuled thermochromic pigments and chrome titanate yellow pigments as fillers in a base film with polyvinyl alcohol and lithium chloride. A Kubelka-Munk four-flux model is constructed to optimize the component proportions of the CCBM. The material has a reversible color change, closely resembles the foliage spectrum in UV-vis-NIR ranges, and imitates the thermal behavior of natural foliage in the mid-infrared regime. These results provide a novel approach to multispectral and hyperspectral camouflage.

2.
FASEB J ; 36(10): e22574, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36165227

RESUMO

In this study, the caprine pancreas has been presented as an alternative to the porcine organ for pancreatic xenotransplantation with lesser risk factors. The obtained caprine pancreas underwent a systematic cycle of detergent perfusion for decellularization. It was perfused using anionic (0.5% w/v sodium dodecyl sulfate) as well as non-ionic (0.1% v/v triton X-100, t-octyl phenoxy polyethoxy ethanol) detergents and washed intermittently with 1XPBS supplemented with 0.1% v/v antibiotic and nucleases in a gravitation-driven set-up. After 48 h, a white decellularized pancreas was obtained, and its extracellular matrix (ECM) content was examined for scaffold-like properties. The ECM content was assessed for removal of cellular content, and nuclear material was evaluated with temporal H&E staining. Quantified DNA was found to be present in a negligible amount in the resultant decellularized pancreas tissue (DPT), thus prohibiting it from triggering any immunogenicity. Collagen and fibronectin were confirmed to be preserved upon trichrome and immunohistochemical staining, respectively. SEM and AFM images reveal interconnected collagen fibril networks in the DPT, confirming that collagen was unaffected. sGAG was visualized using Prussian blue staining and quantified with DMMB assay, where DPT has effectively retained this ECM component. Uniaxial tensile analysis revealed that DPT possesses better elasticity than NPT (native pancreatic tissue). Physical parameters like tensile strength, stiffness, biodegradation, and swelling index were retained in the DPT with negligible loss. The cytocompatibility analysis of DPT has shown no cytotoxic effect for up to 72 h on normal insulin-producing cells (MIN-6) and cancerous glioblastoma (LN229) cells in vitro. The scaffold was recellularized using isolated mouse islets, which have established in vitro cell proliferation for up to 9 days. The scaffold received at the end of the decellularization cycle was found to be non-toxic to the cells, retained biological and physical properties of the native ECM, suitable for recellularization, and can be used as a safer and better alternative as a transplantable organ from a xenogeneic source.


Assuntos
Detergentes , Insulinas , Animais , Antibacterianos/farmacologia , Colágeno/metabolismo , DNA/metabolismo , Matriz Extracelular Descelularizada , Detergentes/química , Detergentes/metabolismo , Detergentes/farmacologia , Etanol/farmacologia , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Cabras , Insulinas/análise , Insulinas/metabolismo , Insulinas/farmacologia , Camundongos , Octoxinol/análise , Octoxinol/metabolismo , Octoxinol/farmacologia , Pâncreas , Estudos Prospectivos , Dodecilsulfato de Sódio/análise , Dodecilsulfato de Sódio/metabolismo , Dodecilsulfato de Sódio/farmacologia , Suínos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
3.
Angew Chem Int Ed Engl ; 62(31): e202306583, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37277318

RESUMO

Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN2 ). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN2 is a promising platform for advancing cell-based applications.


Assuntos
Nanopartículas Metálicas , Nanocápsulas , Nanopartículas , Ouro , Biomimética/métodos , Matriz Extracelular
4.
J Mater Sci Mater Med ; 33(3): 25, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190908

RESUMO

BACKGROUND: There is a continuous research in the area of biomimetic coatings on the titanium (Ti) implant surfaces for improved survival and long-term successful outcomes in the field of dentistry and orthopedics. In-vitro approaches are ideal systems for studying cell-material interactions without complexity and interference observed in in-vivo models. PURPOSE: The present study was undertaken to evaluate the osteoblast characteristics and function on Ti substrates coated with the novel composite coating of ceramic apatite-wollastonite (AW) and polymer chitosan. MATERIALS AND METHODS: Ti substrate coated with composite AW-Chitosan was synthesized, using electrophoretic deposition. MG-63 cells were seeded onto the coated substrates and cellular morphology and growth was assessed using Scanning Electron Microscopy (SEM) and Laser Scanning Microscopy (LSM). Osteocalcin expression of the seeded cells was assessed by FITC tagging and LSM analysis. Alizarin Red S staining and Confocal LSM (CSLM) analysis was used to study the in-vitro mineralization on the titanium samples. RESULTS: The AW-Chitosan coating on Ti samples by electrophoretic deposition exerted significant positive influence on cell proliferation, growth and mineralization as compared to uncoated titanium samples. Scanning electron microscopy and laser confocal microscopy experiments revealed that the coating was non-toxic to cells, enhanced adhesion and proliferation of MG-63 cells. Increased functional activity was observed by increased production of bone-specific protein osteocalcin and mineralized calcium through day 7 and 14. CONCLUSIONS: The present study underscores that optimal inorganic-organic phase nanocomposite crack-free coating created on Ti by simple, cost-effective electrophoretic deposition technique may have osteoconductive potential and may have wide application in the field of implantology. Graphical abstract.


Assuntos
Quitosana , Nanocompostos , Apatitas , Compostos de Cálcio , Materiais Revestidos Biocompatíveis , Osteoblastos , Silicatos , Propriedades de Superfície , Titânio
5.
Sci Technol Adv Mater ; 22(1): 571-582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408551

RESUMO

Much research has been conducted on fabricating biomimetic biomaterials in vitro. Tissue engineering approaches are often conducted by combining cells, scaffolds, and growth factors. However, the degradation rate of scaffolds is difficult to control and the degradation byproducts occasionally limit tissue regeneration. To overcome these issues, we have developed a novel system using a thermo-responsive hydrogel that forms scaffold-free, three-dimensional (3D) cell constructs with arbitrary size and morphology. 3D cell constructs prepared using bone marrow-derived stromal stem cells (BMSCs) exhibited self-organizing ability and formed bone-like tissue with endochondral ossification. Endothelial cells were then introduced into the BMSC construct and a vessel-like structure was formed within the constructs. Additionally, the bone formation ability was promoted by endothelial cells and cell constructs could be freeze-dried to improve their clinical application. A pre-treatment with specific protein protectant allowed for the fabrication of novel bone substitutes composed only of cells. This 3D cell construct technology using thermo-responsive hydrogels was then applied to other cell species. Cell constructs composed of dental pulp stem cells were fabricated, and the resulting construct regenerated pulp-like tissue within a human pulpless tooth. In this review, we demonstrate the approaches for the in vitro fabrication of bone and dental pulp-like tissue using thermo-responsive hydrogels and their potential applications.

6.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445255

RESUMO

One of the most important features of striated cardiac muscle is the excitability that turns on the excitation-contraction coupling cycle, resulting in the heart blood pumping function. The function of the heart pump may be impaired by events such as myocardial infarction, the consequence of coronary artery thrombosis due to blood clots or plaques. This results in the death of billions of cardiomyocytes, the formation of scar tissue, and consequently impaired contractility. A whole heart transplant remains the gold standard so far and the current pharmacological approaches tend to stop further myocardium deterioration, but this is not a long-term solution. Electrically conductive, scaffold-based cardiac tissue engineering provides a promising solution to repair the injured myocardium. The non-conductive component of the scaffold provides a biocompatible microenvironment to the cultured cells while the conductive component improves intercellular coupling as well as electrical signal propagation through the scar tissue when implanted at the infarcted site. The in vivo electrical coupling of the cells leads to a better regeneration of the infarcted myocardium, reducing arrhythmias, QRS/QT intervals, and scar size and promoting cardiac cell maturation. This review presents the emerging applications of intrinsically conductive polymers in cardiac tissue engineering to repair post-ischemic myocardial insult.


Assuntos
Arritmias Cardíacas , Materiais Biocompatíveis , Condutividade Elétrica , Infarto do Miocárdio , Miocárdio/metabolismo , Regeneração/efeitos dos fármacos , Alicerces Teciduais/química , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/terapia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Humanos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Engenharia Tecidual
7.
J Theor Biol ; 486: 110058, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31678097

RESUMO

Here we mimic the mechanical properties of native fascia to design surgical mesh for fascia replacement. Despite the widespread acceptance of synthetic materials as tissue scaffolds for pelvic floor disorders, mechanical property mismatch between mesh and adjacent native tissue drives fibrosis and erosion, leading the FDA to remove several surgical meshes from the market. However, autologous tissue does not induce either fibrosis or adjacent tissue erosion, suggesting the potential for biomimetic surgical mesh. In this study, we determined the design rules for mesh that mimics native fascia by mathematically modeling multi-component polymer networks, composed of elastin-like and collagen-like fibers, using a spring-network model. To validate the model, we measured the stress-strain curves of native bovine and nonhuman primate (Macaca mulatta) abdominal fascia in both toe and linear regions. We find that the stiffer collagen-like fibers must remain limp until the elastin-like fibers extend to the initial length of spanning collagen-like fibers under uniaxial tension. Comparing model results to experiment determines the product of fiber volume fraction and elastic modulus, a critical design parameter. Dual fiber mesh with mechanical properties that mimic fascia are feasible. These results have broad application to a wide range of soft tissue replacements including ~200,000 surgeries/year for pelvic floor disorders, because standard-of-care mesh contain only stiffer polymers that behave more like collagen than native tissue.


Assuntos
Biomimética , Telas Cirúrgicas , Animais , Bovinos , Fáscia , Fenômenos Mecânicos , Alicerces Teciduais
8.
Molecules ; 25(21)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153127

RESUMO

The development and characterization of biomaterials for bone replacement in case of large defects in preconditioned bone (e.g., osteoporosis) require close cooperation of various disciplines. Of particular interest are effects observed in vitro at the cellular level and their in vivo representation in animal experiments. In the present case, the material-based alteration of the ratio of osteoblasts to osteoclasts in vitro in the context of their co-cultivation was examined and showed equivalence to the material-based stimulation of bone regeneration in a bone defect of osteoporotic rats. Gelatin-modified calcium/strontium phosphates with a Ca:Sr ratio in their precipitation solutions of 5:5 and 3:7 caused a pro-osteogenic reaction on both levels in vitro and in vivo. Stimulation of osteoblasts and inhibition of osteoclast activity were proven during culture on materials with higher strontium content. The same material caused a decrease in osteoclast activity in vitro. In vivo, a positive effect of the material with increased strontium content was observed by immunohistochemistry, e.g., by significantly increased bone volume to tissue volume ratio, increased bone morphogenetic protein-2 (BMP2) expression, and significantly reduced receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) ratio. In addition, material degradation and bone regeneration were examined after 6 weeks using stage scans with ToF-SIMS and µ-CT imaging. The remaining material in the defects and strontium signals, which originate from areas exceeding the defect area, indicate the incorporation of strontium ions into the surrounding mineralized tissue. Thus, the material inherent properties (release of biologically active ions, solubility and degradability, mechanical strength) directly influenced the cellular reaction in vitro and also bone regeneration in vivo. Based on this, in the future, materials might be synthesized and specifically adapted to patient-specific needs and their bone status.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio , Fêmur , Gelatina , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/terapia , Fosfatos , Estrôncio , Animais , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Técnicas de Cocultura , Feminino , Fêmur/lesões , Fêmur/metabolismo , Fêmur/patologia , Gelatina/química , Gelatina/farmacologia , Osteoblastos/patologia , Osteoclastos/patologia , Osteoporose/metabolismo , Osteoporose/patologia , Fosfatos/química , Fosfatos/farmacologia , Ratos , Ratos Sprague-Dawley , Estrôncio/química , Estrôncio/farmacologia
9.
Int J Mol Sci ; 20(17)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484291

RESUMO

The development of cell culture systems for the naturalistic propagation, self-renewal and differentiation of cells ex vivo is a high goal of molecular engineering. Despite significant success in recent years, the high cost of up-scaling cultures, the need for xeno-free culture conditions, and the degree of mimicry of the natural extracellular matrix attainable in vitro using designer substrates continue to pose obstacles to the translation of cell-based technologies. In this regard, the ZT biopolymer is a protein-based, stable, scalable, and economical cell substrate of high promise. ZT is based on the naturally occurring assembly of two human proteins: titin-Z1Z2 and telethonin. These protein building blocks are robust scaffolds that can be conveniently functionalized with full-length proteins and bioactive peptidic motifs by genetic manipulation, prior to self-assembly. The polymer is, thereby, fully encodable. Functionalized versions of the ZT polymer have been shown to successfully sustain the long-term culturing of human embryonic stem cells (hESCs), human induced pluripotent stem cells (hiPSCs), and murine mesenchymal stromal cells (mMSCs). Pluripotency of hESCs and hiPSCs was retained for the longest period assayed (4 months). Results point to the large potential of the ZT system for the creation of a modular, pluri-functional biomaterial for cell-based applications.


Assuntos
Biopolímeros/metabolismo , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas , Camundongos , Células-Tronco Pluripotentes/metabolismo
10.
Adv Exp Med Biol ; 1064: 93-107, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30471028

RESUMO

In recent tissue engineering applications, the advance of biomaterials has focused on the devising of biomimetic materials that are directing new tissue formation and capable of causing specific cellular responses. These advances can be controlled by modifying the devising parameters of the materials. The biomimetic materials potentially mimic many roles of ECM in tissues. For the homogeneous distribution and biocompatibility of scaffolds by cell migration with biomimetic materials, cell migration is studied because it has a important role in physiological phenomenon and in pathologies; cancer metastasis, immune response or embryonic development. This review discusses the migration of cells with biomimetic materials for tissue engineering. It is also summarized that the recent advances of cell migration with biomimetic materials in 2-D and 3-D for tissue engineering.


Assuntos
Materiais Biomiméticos , Movimento Celular , Matriz Extracelular , Engenharia Tecidual , Materiais Biocompatíveis , Humanos , Alicerces Teciduais
11.
Proc Natl Acad Sci U S A ; 111(3): 990-5, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24395775

RESUMO

Synthetic matrices emulating the physicochemical properties of tissue-specific ECMs are being developed at a rapid pace to regulate stem cell fate. Biomaterials containing calcium phosphate (CaP) moieties have been shown to support osteogenic differentiation of stem and progenitor cells and bone tissue formation. By using a mineralized synthetic matrix mimicking a CaP-rich bone microenvironment, we examine a molecular mechanism through which CaP minerals induce osteogenesis of human mesenchymal stem cells with an emphasis on phosphate metabolism. Our studies show that extracellular phosphate uptake through solute carrier family 20 (phosphate transporter), member 1 (SLC20a1) supports osteogenic differentiation of human mesenchymal stem cells via adenosine, an ATP metabolite, which acts as an autocrine/paracrine signaling molecule through A2b adenosine receptor. Perturbation of SLC20a1 abrogates osteogenic differentiation by decreasing intramitochondrial phosphate and ATP synthesis. Collectively, this study offers the demonstration of a previously unknown mechanism for the beneficial role of CaP biomaterials in bone repair and the role of phosphate ions in bone physiology and regeneration. These findings also begin to shed light on the role of ATP metabolism in bone homeostasis, which may be exploited to treat bone metabolic diseases.


Assuntos
Adenosina/metabolismo , Fosfatos de Cálcio/química , Regulação da Expressão Gênica , Células-Tronco/citologia , Trifosfato de Adenosina/metabolismo , Materiais Biocompatíveis/química , Osso e Ossos/metabolismo , Fosfatos de Cálcio/metabolismo , Diferenciação Celular , Células Cultivadas/citologia , Cromatografia Líquida de Alta Pressão , Homeostase , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Fenótipo , Fosfatos/metabolismo , RNA Interferente Pequeno/metabolismo , Receptor A2B de Adenosina/metabolismo , Regeneração , Transdução de Sinais , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
12.
Adv Mater ; 36(26): e2401982, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38609077

RESUMO

Corrosion activities and biofouling pose significant challenges for marine facilities, resulting in substantial economic losses. Inspired by the "brick&mortar" structure of pearls, a novel nanocomposite coating (Pun-HJTx) with long-lasting anticorrosion and intelligent antifouling modes is fabricated by integrating a compatible MoS2/MXene heterostructure as the "brick" into a polyurea-modified PDMS (Pun) acting as "mortar." Notably, the presence of multiple hydrogen bonds within the coating effectively reduces the pinholes resulted from solution volatilizing. In the dark, where fouling adhesion and microbial corrosion activities are weakened, the MoS2/MXene plays a role in contact bactericidal action. Conversely, during daylight when fouling adhesion and microbial corrosion activities intensify, the coating releases reactive oxygen species (such as hydroxyl radicals and superoxide ions) to counteract fouling adhesion. Additionally, the coating exhibits multisource self-healing performance under heated or exposed to light (maximum self-healing rate can reach 99.46%) and proves efficient self-cleaning performance and adhesion strength (>2.0 Mpa), making it highly suitable for various practical marine applications. Furthermore, the outstanding performance of the Pun-HJT1 is maintained for ≈180 days in real-world marine conditions, which proving its practicality and feasibility in real shallow sea environments.

13.
Clin Med Insights Oncol ; 18: 11795549241236896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645894

RESUMO

By modifying immune cells, immunotherapy can activate immune response to establish long-term immune memory and prevent tumor recurrence. However, their effectiveness is largely constricted by the poor immunogenicity, immune escape, and immune tolerance of the tumor. This is related to the characteristics of the tumor itself, such as genome instability and mutation. The combination of various nanocarriers with tumor immunotherapy is beneficial for overcoming the shortcomings of traditional immunotherapy. Nanocarriers coated by cell membranes can extend blood circulation time, improve ability to evade immune clearance, and enhance targeting, thus significantly enhancing the efficacy of immunotherapy and showing great potential in tumor immunotherapy. This article reviews the application research progress of different types of cell membrane-modified nanocarriers in tumor immunotherapy, immunotherapy combination therapy, and tumor vaccines, and provides prospects for future research.

14.
Adv Mater ; 36(9): e2308972, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37917884

RESUMO

Slippery liquid-infused porous surfaces (SLIPS) have received widespread attention in the antifouling field. However, the reduction in antifouling performance caused by lubricant loss limits their application in marine antifouling. Herein, inspired by the skin of a poison dart frog which contains venom glands and mucus, a porous liquid (PL) based on ZIF-8 is prepared as a lubricant and injected into a silicone polyurethane (SPU) matrix to construct a new type of SLIPS for marine antifouling applications: the slippery porous-liquid-infused porous surface (SPIPS). The SPIPS consists of a responsive antifoulant-releasing switch between "defensive" and "offensive" antifouling modes to intelligently enhance the antifouling effect after lubricant loss. The SPIPS can adjust antifouling performance to meet the antifouling requirements under different light conditions. The wastage of antifoulants is reduced, thereby effectively maintaining the durability and service life of SLIPS materials. The SPIPS exhibits efficient lubricant self-replenishment, self-cleaning, anti-protein, anti-bacterial, anti-algal, and self-healing (97.48%) properties. Furthermore, it shows satisfactory 360-day antifouling performance in actual marine fields during boom seasons, demonstrating the longest antifouling lifespan in the field tests of reported SLIPS coatings. Hence, the SPIPS can effectively promote the development of SLIPS for neritic antifouling.


Assuntos
Incrustação Biológica , Animais , Incrustação Biológica/prevenção & controle , Porosidade , Lubrificantes , Rãs Venenosas , Poliuretanos
15.
J Colloid Interface Sci ; 635: 456-465, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36599243

RESUMO

Compared with the individuals, the collective behavior of biotic communities could show certain superior characteristics. Inspired by this idea and based on the conjugation between phenylboronic acid-grafted mesoporous silica nanoparticles and the polysaccharide functionalized membrane of proteinosomes, a type of proteinosomes-based aggregations was constructed. We demonstrated the emergent characteristics of proteinosomes aggregations including accelerated settling velocity and population surviving by sacrificing outside members for the inside. Moreover, this kind of "hand in hand" architecture provided the proteinosomes aggregations with the characteristic of resistance to the negative pressure phagocytosis of micropipette, as well as enhancing utilization rate of the encapsulated enzymes. Overall, it is anticipated that the construction and application of proteinosomes aggregations could contribute to advance the functionality of life-like assembled biomaterial in another way.

16.
J Adv Res ; 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37659687

RESUMO

BACKGROUND: Since the inception of the term "Biomimetics" in 1991, the concept of utilizing natural solutions or deriving inspiration from nature to address contemporary engineering challenges has gained significant attention within the scientific community. Organisms, in order to thrive in harsh environments, have evolved a wide range of micro/nanostructured surfaces, which serve as a rich source of inspiration for the development of artificial micro/nano-structured surfaces. These natural adaptations provide valuable insights and novel pathways for fabricating such surfaces. AIM: To conclude recent advances in micro/nano-structured surfaces from four aspects: biomimetic micro-structured surfaces of plants and animals, properties and applications of biomimetic surfaces, methods of preparations, and their limitation. KEY SCIENTIFIC CONCEPTS: Artificial micro/nano-structured surfaces inspired by animals and plants are classified and demonstrated according to their living environment. The performances, principles and preparation techniques of natural superhydrophobic surfaces, slippery liquid-infused porous surfaces (SLIPS), anisotropic surfaces, etc. are described in detail. Moreover, the pros and cons of each preparation measures are compared and the challenges developing large-scale, cost-effective surface microstructure preparation processes are pointed out. In the end, the development trends of artificial micro/nano-structured surface are forecasted.

17.
Adv Funct Mater ; 22(15): 3170-3180, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23526705

RESUMO

Biomaterials such as self-assembling biological complexes have demonstrated a variety of applications in materials science and nanotechnology. The functionality of protein-based materials, however, is often limited by the absence or locations of specific chemical conjugation sites. In this investigation, we developed a new strategy for loading organic molecules into the hollow cavity of a protein nanoparticle that relies only on non-covalent interactions, and we demonstrated its applicability in drug delivery. Based on a biomimetic model that incorporates multiple phenylalanines to create a generalized binding site, we retained and delivered the antitumor compound doxorubicin by redesigning a caged protein scaffold. Through an iterative combination of structural modeling and protein engineering, we obtained new variants of the E2 subunit of pyruvate dehydrogenase with varying levels of drug-carrying capabilities. We found that an increasing number of introduced phenylalanines within the scaffold cavity generally resulted in greater drug loading capacities. Drug loading levels could be achieved that were greater than conventional nanoparticle delivery systems. These protein nanoparticles containing doxorubicin were taken up by breast cancer cells and induced significant cell death. Our novel approach demonstrates a universal strategy to design de novo hydrophobic binding domains within protein-based scaffolds for molecular encapsulation and transport, and it broadens the ability to attach guest molecules to this class of materials.

18.
ACS Biomater Sci Eng ; 8(6): 2676-2683, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35616239

RESUMO

Metal oxide affinity chromatography (MOAC) is considered to be one of the most effective methods for phosphopeptide enrichment. However, most of the materials used in the method are powder; frequent centrifugation is necessitated during the enrichment process, and potential risks of loss of peptides and materials and clogging of the column employed for liquid chromatography-mass spectrometry (LC-MS) arise. Moreover, the reusability of these materials to achieve sustainability was hardly investigated. To overcome these limitations, herein, inorganic titanium dioxide (TiO2) was coated onto the skeletal surface of the organic cellulose monolith (CM) material with a coral-like structure via a sol-gel method. This produced an organic-inorganic hybrid TiO2-CM material, which contained a combination of organic and inorganic substances, making it mimic the mollusk shell in terms of composition. The prepared TiO2-CM material as monolith exhibited excellent mechanical strength and did not break during the enrichment process; thus, the tedious implementation of multiple centrifugation cycles was prevented, thereby streamlining the experimental procedure and avoiding the loss of peptides and materials. Moreover, a large amount of TiO2 was introduced onto the surface of the CM material, and thus, the resultant TiO2-CM material exhibited a large surface area. As a result, the fabricated TiO2-CM material was successfully applied to the enrichment of phosphopeptides obtained from the tryptic digests of a BSA/ß-casein (mass ratio, 500/1) mixture. The results were superior to those achieved for commercial TiO2 beads, confirming that TiO2-CM has excellent selectivity for phosphopeptides and reusability. Furthermore, 9287 unique phosphopeptides derived from the 2661 phosphoproteins were successfully identified from two milligrams of tryptic digests of Hela cell exosomes obtained through five independent replications after enriching using the TiO2-CM material. The results indicated that the material has good application prospects in the analysis of protein phosphorylation. Furthermore, TiO2-CM consists of green and cheap cellulose as the skeleton, and its synthesis process is environment-friendly, simple, and inexpensive.


Assuntos
Celulose , Fosfopeptídeos , Biomimética , Células HeLa , Humanos , Fosfopeptídeos/análise , Fosfopeptídeos/química , Titânio
19.
Front Cell Neurosci ; 16: 868323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480961

RESUMO

Ischemic stroke remains the leading cause of death and disability, while the main mechanisms of dominant neurological damage in stroke contain excitotoxicity, oxidative stress, and inflammation. The clinical application of many neuroprotective agents is limited mainly due to their inability to cross the blood-brain barrier (BBB), short half-life and low bioavailability. These disadvantages can be better eliminated/reduced by nanoparticle as the carrier of these drugs. This review expounded the currently hot researched nanomedicines from the perspective of the mechanism of ischemic stroke. In addition, this review describes the bionic nanomedicine delivery strategies containing cells, cell membrane vesicles and exosomes that can effectively avoid the risk of clearance by the reticuloendothelial system. The potential challenges and application prospect for clinical translation of these delivery platforms were also discussed.

20.
Biomater Adv ; 134: 112550, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35523647

RESUMO

Implant-related infections at the early healing period are considered one of the main risk factors in implant failure. Designing coatings that control bacterial adhesion and have cell stimulatory behavior remains a challenging strategy for dental implants. Here, we used plasma electrolytic oxidation (PEO) to produce antimicrobial coatings on commercially pure titanium (cpTi) using bioactive elements (calcium and phosphorus) and different copper (Cu) sources: copper acetate (CuAc), copper sulfate (CuS), and copper oxide (CuO); coatings containing only Ca and P (CaP) served as controls. Cu sources drove differential physical and chemical surface features of PEO coatings, resulting in tailorable release kinetics with a sustained Cu ion release over 10 weeks. The antibacterial effects of Cu-containing coatings were roughness-dependent. CuAc coating exhibited optimal properties in terms of its hydrophilicity, pores density, and limited surface roughness, which provided the most robust antibacterial activity combined with appropriate responses of human primary stem cells and angiogenic cells. Our data indicate that Cu source selection largely determines the functionality of Cu-containing PEO coatings regarding their antibacterial efficacy and cytocompatibility.


Assuntos
Materiais Revestidos Biocompatíveis , Cobre , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Cobre/química , Humanos , Propriedades de Superfície , Titânio/farmacologia
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