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1.
Biomacromolecules ; 25(3): 1950-1958, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38334281

RESUMEN

Targeted photodynamic therapy (PDT) offers advantages over nontargeted approaches, including improved selectivity, efficacy, and reduced side effects. This study developed star-shaped glycopolymeric photosensitizers using porphyrin-based initiators via ATRP. Incorporating a porphyrin core gave the polymers fluorescence and ROS generation, while adding fructose improved solubility and targeting capabilities. The photosensitizers had high light absorption, singlet oxygen production, specificity, low dark toxicity, and biocompatibility. The glycopolymers with longer sugar arms and higher density showed better uptake on MCF-7 and MDA-MB-468 cells compared to HeLa cells, indicating enhanced targeting capabilities. Inhibition of endocytosis confirmed the importance of the GLUT5 receptor. The resulting polymers exhibited good cytocompatibility under dark conditions and satisfactory PDT under light irradiation. Interestingly, the polymers containing fructose have a GLUT5-dependent elimination effect on the MCF-7 and MDA-MB-468 cells. The intracellular ROS production followed a similar pattern, indicating that the fructose polymer exhibits specific targeting toward cells with GLUT5 receptors.


Asunto(s)
Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Células HeLa , Especies Reactivas de Oxígeno , Porfirinas/farmacología , Polímeros/farmacología , Fructosa/farmacología
2.
Biomacromolecules ; 24(5): 2301-2313, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37067047

RESUMEN

The aggregation-caused quenching, premature drug release, and hypoxia-caused resistance of photodynamic therapy (PDT) are challenges in the design and preparation of novel porphyrin-containing photosensitizers. In this work, a series of block copolymers consisting of a hydrophilic glycopolymer block and a porphyrin-containing hydrophobic block were prepared via reversible addition-fragmentation chain transfer polymerization. The polymeric photosensitizers generate singlet oxygen and excellent PDT against HepG2, which can be strengthened by the addition of cholic acid. To combine with chemotherapy, doxorubicin (Dox) was successfully loaded into copolymers, which were observed to be more phototoxic, indicating that the therapeutic benefit of the synergistic effect of PDT and chemotherapy is better than their simple combination. The sugar-cell-specific interaction of galactose-containing photosensitizers results in a stronger mean fluorescent index (MFI) intracellular uptake in HepG2 cells in vitro compared to L929 and MCF-7 cells. These polymeric nanoplatforms present a versatile and effective avenue for developing synergistic therapy for cancer treatment.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotosensibilizantes/química , Fotoquimioterapia/métodos , Ácido Cólico/farmacología , Nanopartículas/química , Doxorrubicina/farmacología , Doxorrubicina/química , Polímeros/farmacología , Polímeros/química , Porfirinas/química , Línea Celular Tumoral
3.
Biomacromolecules ; 23(12): 5074-5083, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36350056

RESUMEN

Porphyrins and their derivatives, representing the second-generation photosensitizers, can generate reactive oxygen species (ROS) and kill tumors upon light irradiation. To compensate for the fluorescence quenching and reduced ROS production caused by aggregation and rigid inherent hydrophobicity of porphyrins, a series of comparable random and block glycopolymers bearing betulin and porphyrin were prepared via RAFT polymerization. Betulin was introduced into the copolymers to decrease aggregation-induced quenching of porphyrins and to improve the photodynamic therapy (PDT) efficiency of copolymers. The characteristics, self-assembly, and photophysical chemistry properties of these copolymers were systemically studied. The effect of polymer structure on photophysical chemistry properties and cellular interaction was investigated as well to demonstrate their potential targeting for PDT applications.


Asunto(s)
Fotoquimioterapia , Porfirinas , Triterpenos , Porfirinas/farmacología , Porfirinas/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Triterpenos/farmacología , Polímeros/química
4.
Small ; 17(33): e2102051, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34309205

RESUMEN

Airborne particulate matters (PM) pose serious health threats to the population, and efficient filtration is needed for indoor and vehicular environments. However, there is an intrinsic conflict between filtration efficiency, air resistance, and service life. In this study, a two-stage electrostatically assisted air (EAA) filtration device is designed and the efficiency-air resistance-filter life envelope is significantly improved by a thin coating of polydopamine (PDA) on the polyethylene terephthalate (PET) coarse filter by in situ dopamine polymerization. The 8 mm thick EAA PDA-140@PET filter has a high filtration efficiency of 99.48% for 0.3 µm particles, low air resistance of 9.5 Pa at a filtration velocity of 0.4 m s-1 , and steady performance up to 30 d. Compared with the bare PET filter, the penetration rate for 0.3 µm particles is lowered by 20×. The coated PDA is of submicron thickness, 10-3  × the gap distance between filter fibers, so low air resistance could be maintained. The filter shows steadily high filtration efficiency and an acceptable increase of air resistance and holds nearly as many particles as its own weight in a 30 day long-term test. The working mechanism of the EAA coarse filter is investigated, and the materials design criteria are proposed.


Asunto(s)
Material Particulado , Tereftalatos Polietilenos , Filtración , Indoles , Polímeros
5.
Macromol Rapid Commun ; 42(3): e2000498, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33336853

RESUMEN

Flexible aliphatic poly(lactic acid) is introduced into polyethylene terephthalate through copolymerization to prepare biodegradable copolyester, which aims to solve the non-degradability of polyethylene terephthalate (PET) and realize the greening of raw materials. In this work, poly(ethylene terephthalate-co-lactic acid) random copolyesters (PETLAs) of lactic acid composition from 10 to 50% is synthesized via one-pot method. The chemical structure and composition, thermal property, and crystallization property of prepared PETLAs resin are characterized. The results shows that the introduction of LA segment forms random copolyester, and the flexible LA segment results in slight decrease in the glass transition temperatures (Tg ), melting point (Tm ), and crystallinity (Xc ) of the copolyesters. The thermal stability of PETLAs is better, and the initial decomposition temperature of PETLA-10 can reach 394 °C. The PETLAs resin exhibits good processability, and PETLAs fibers are prepared by melt spinning. The strength of PETLA-10 fiber can reach 260 MPa after drawing treatment, and the elongation at break can reach 130%. Taking advantage of their features, PETLAs as an innovative bio-based polymer are expected to achieve ecofriendly applications in the fields of fiber, plastic, and film.


Asunto(s)
Polímeros , Cristalización , Polimerizacion , Temperatura
6.
Macromol Rapid Commun ; 39(21): e1800337, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30118163

RESUMEN

Hydrogels are an important class of soft materials with high water retention that exhibit intelligent and elastic properties and have promising applications in the fields of biomaterials, soft machines, and artificial tissue. However, the low mechanical strength and limited functions of traditional chemically cross-linked hydrogels restrict their further applications. Natural materials that consist of stiff and soft components exhibit high mechanical strength and functionality. Among artificial soft materials, nanocomposite hydrogels are analogous to these natural materials because of the synergistic effects of nanoparticle (NP) polymers in hydrogels construction. In this article, the structural design and properties of nanocomposite hydrogels are summarized. Furthermore, along with the development of nanocomposite hydrogel-based devices, the shaping and potential applications of hydrogel devices in recent years are highlighted. The influence of the interactions between NPs and polymers on the dispersion as well as the structural stability of nanocomposite hydrogels is discussed, and the novel stimuli-responsive properties induced by the synergies between functional NPs and polymeric networks are reviewed. Finally, recent progress in the preparation and applications of nanocomposite hydrogels is highlighted. Interest in this field is growing, and the future and prospects of nanocomposite hydrogels are also reviewed.


Asunto(s)
Hidrogeles/síntesis química , Nanocompuestos/química , Nanopartículas/química , Polímeros/química , Animales , Humanos , Hidrogeles/química , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie
7.
Macromol Rapid Commun ; 36(5): 477-82, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25611464

RESUMEN

Novel thermosensitive nanocomposite (NC) hydrogels consisting of organic/inorganic networks are prepared via in situ free radical polymerization of 2-(2-methoxyethoxy) ethyl methacrylate (MEO2 MA) and oligo(ethylene glycol) methacrylate (OEGMA) in the presence of inorganic cross-linker clay in aqueous solution. The obtained clay/P(MEO2 MA-co-OEGMA) hydrogels exhibit double volume phase transition temperatures, an upper critical solution temperature (UCST), and a lower critical solution temperature (LCST), which can be controlled between 5 and 85 °C by varying the fraction of OEGMA units and the weight percentage of cross-linker clay. These new types of NC hydrogels with excellent reversible thermosensitivity are promising for temperature-sensitive applications such as smart optical switches.


Asunto(s)
Hidrogeles/química , Metacrilatos/química , Nanocompuestos/química , Polímeros/química , Temperatura , Silicatos de Aluminio/química , Arcilla , Radicales Libres/química , Transición de Fase , Polimerizacion , Soluciones/química
8.
ACS Biomater Sci Eng ; 10(6): 3718-3726, 2024 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-38716490

RESUMEN

The performance of dental resin composites is crucially influenced by the sizes and distributions of inorganic fillers. Despite the investigation of a variety of functional particles, glass fillers and nanoscale silica are still the predominant types in dental materials. However, achieving an overall improvement in the performance of resin composites through the optimization of their formulations remains a challenge. This work introduced a "dense" microhybrid filler system with 85 wt % filler loading, leading to the preparation of self-developed resin composites (SRCs). Comparative evaluations of these five SRCs against four commercial products were performed, including mechanical property, polymerization conversion, and shrinkage, along with water sorption and solubility and wear resistance. The results showed that among all SRC groups, SRC3 demonstrated superior mechanical performance, high polymerization conversion, reduced shrinkage, low water absorption and solubility, and acceptable wear resistance. In contrast to commercial products, this optimal SRC3 material was comparable to Z350 XT in flexural and diametral tensile strength and better in flexural modulus and surface hardness. The use of a "dense" microhybrid filler system in the development of resin composites provides a balance between physicochemical property and wear resistance, which may be a promising strategy for the development of composite products.


Asunto(s)
Resinas Compuestas , Ensayo de Materiales , Resinas Compuestas/química , Solubilidad , Resistencia a la Tracción , Materiales Dentales/química , Polimerizacion , Poliuretanos/química , Propiedades de Superficie , Dureza , Resinas Acrílicas/química
9.
Dent Mater ; 40(6): 941-950, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38719709

RESUMEN

OBJECTIVE: Bisphenol A glycidyl methacrylate (Bis-GMA) is of great importance for dental materials as the preferred monomer. However, the presence of bisphenol-A (BPA) core in Bis-GMA structure causes potential concerns since it is associated with endocrine diseases, developmental abnormalities, and cancer lesions. Therefore, it is desirable to develop an alternative replacement for Bis-GMA and explore the intrinsic relationship between monomer structure and resin properties. METHODS: Here, the betulin maleic diester derivative (MABet) was synthesized by a facile esterification reaction using plant-derived betulin and maleic anhydride as raw materials. Its chemical structure was confirmed by 1H and 13C NMR spectra, FT-IR spectra, and HR-MS, respectively. The as-synthesized MABet was then used as polymerizable comonomer to partially or completely substitute Bis-GMA in a 50:50 Bis-GMA: TEGDMA resin (5B5T) to formulate dental restorative resins. These were then determined for the viscosity behavior, light transmittance, real-time degree of conversion, residual monomers, mechanical performance, cytotoxicity, and antibacterial activity against Streptococcus mutans (S. mutans) in detail. RESULTS: Among all experimental resins, increasing the MABet concentration to 50 wt% made the resultant 5MABet5T resin have a maximum in viscosity and appear dark yellowish after polymerization. In contrast, the 1MABet4B5T resin with 10 wt% MABet possessed comparable shear viscosity and polymerization conversion (46.6 ± 1.0% in 60 s), higher flexural and compressive strength (89.7 ± 7.8 MPa; 345.5 ± 14.4 MPa) to those of the 5B5T control (48.5 ± 0.6%; 65.7 ± 6.7 MPa; 223.8 ± 57.1 MPa). This optimal resin also had significantly lower S. mutans colony counts (0.35 ×108 CFU/mL) than 5B5T (7.6 ×108 CFU/mL) without affecting cytocompatibility. SIGNIFICANCE: Introducing plant-derived polymerizable MABet monomer into dental restorative resins is an effective strategy for producing antibacterial dental materials with superior physicochemical property.


Asunto(s)
Antibacterianos , Bisfenol A Glicidil Metacrilato , Ensayo de Materiales , Streptococcus mutans , Triterpenos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Triterpenos/química , Triterpenos/farmacología , Streptococcus mutans/efectos de los fármacos , Bisfenol A Glicidil Metacrilato/química , Viscosidad , Materiales Dentales/química , Materiales Dentales/farmacología , Materiales Dentales/síntesis química , Polimerizacion , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacología , Resinas Compuestas/química , Resinas Compuestas/síntesis química , Resinas Compuestas/farmacología , Polietilenglicoles/química , Espectroscopía Infrarroja por Transformada de Fourier , Ácido Betulínico
10.
Water Res ; 256: 121594, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38615603

RESUMEN

Membrane distillation (MD) has emerged as a promising technology for desalination and concentration of hypersaline brine. However, the efficient preparation of a structurally stable and salinity-resistant membrane remains a significant challenge. In this study, an amphiphobic polytetrafluoroethylene nanofibrous membrane (PTFE NFM) with exceptional resistance to scaling has been developed, using an energy-efficient method. This innovative approach avoids the high-temperature sintering treatment, only involving electrospinning with PTFE/PVA emulsion and subsequent low-temperature crosslinking and fluorination. The impact of the PVA and PTFE contents, as well as the crosslinking and subsequent fluorination on the morphology and MD performance of the NFM, were systematically investigated. The optimized PTFE NFM displayed robust amphiphobicity, boasting a water contact angle of 155.2º and an oil contact angle of 132.7º. Moreover, the PTFE NFM exhibited stable steam flux of 52.1 L·m-2·h-1 and 26.7 L·m-2·h-1 when fed with 3.5 wt % and 25.0 wt % NaCl solutions, respectively, and an excellent salt rejection performance (99.99 %, ΔT = 60 °C) in a continuous operation for 24 h, showing exceptional anti-scaling performance. It also exhibited stable anti-wetting and anti-fouling properties against surfactants (sodium dodecyl sulfate) and hydrophobic contaminants (diesel oil). These results underscore the significant potential of the PTFE nanofibrous membrane for practical applications in desalination, especially in hypersaline or polluted aqueous environments.


Asunto(s)
Destilación , Membranas Artificiales , Nanofibras , Politetrafluoroetileno , Politetrafluoroetileno/química , Nanofibras/química , Destilación/métodos , Halogenación , Purificación del Agua/métodos
11.
Dent Mater ; 40(8): e1-e10, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38821838

RESUMEN

OBJECTIVE: Although glass fibers are more common, quartz fibers (QFs) are also considered as the ideal reinforcing material in dentistry, due to their superior mechanical strength, high purity, and good photoconductive properties. However, the relatively inert surfaces limit their further applications. Therefore, the aim of this study is to modify the fiber surface properties to improve the interfacial interactions with polymeric resins. METHODS: In this study, we systematically introduced four different surface modification strategies onto short quartz fibers (SQFs) for the preparation of dental composites. Particularly, the acid etching was a facile way to create mechanical interlocking structures. In addition, the silanization process, the sol-gel treatment, and the polymer grafting were further proposed to increase the surface roughness and the reactive sites. The effect of surface modifications on the fiber surface morphological changes, mechanical properties, water stability, and in vitro cell viability of dental composites were investigated. RESULTS: Among all surface-modified SQFs, SQFs-POSS (SQFs modified with methacrylate-POSS) exhibited the roughest surface morphology and highest grafting rates compared with other three materials. Furthermore, all these SQFs were applied as reinforcements to make dimethacrylate-based dental resin composites. Of all fillers, SQFs-POSS demonstrated the best reinforcing effect, providing significantly higher improvements of 55.7 %, 114.3 %, and 164.7 % for flexural strength, flexural modulus, and breaking energy, respectively, over those of SQFs-filled composite. The related reinforcing mechanism was further investigated. The SQFs-POSS-filled composite also exhibited the best water stability performance and in vitro cell viability. SIGNIFICANCE: This work provided valuable insights into the optimization of filler-matrix interaction through fiber surface modifications. Specifically, SQFs-POSS markedly outperformed other formulations in terms of the physicochemical performance and in vitro cytotoxicity, which offers possibilities for developing high-performance dental composites for clinical applications in restorative dentistry.


Asunto(s)
Supervivencia Celular , Resinas Compuestas , Ensayo de Materiales , Cuarzo , Propiedades de Superficie , Resinas Compuestas/química , Cuarzo/química , Técnicas In Vitro , Animales , Ratones , Resinas Acrílicas/química , Materiales Dentales/química
12.
ACS Appl Mater Interfaces ; 16(27): 34578-34590, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38946497

RESUMEN

Meeting the exacting demands of wound healing encompasses rapid coagulation, superior exudate absorption, high antibacterial efficacy, and imperative support for cell growth. In this study, by emulating the intricate structure of natural skin, we prepare a multifunctional porous bilayer artificial skin to address these critical requirements. The bottom layer, mimicking the dermis, is crafted through freeze-drying a gel network comprising carboxymethyl chitosan (CMCs) and gelatin (GL), while the top layer, emulating the epidermis, is prepared via electrospinning poly(l-lactic acid) (PLLA) nanofibers. With protocatechuic aldehyde and gallium ion complexation (PA@Ga) as cross-linking agents, the bottom PA@Ga-CMCs/GL layer featured an adjustable pore size (78-138 µm), high hemostatic performance (67s), and excellent bacterial inhibition rate (99.9%), complemented by an impressive liquid-absorbing capacity (2000% swelling rate). The top PLLA layer, with dense micronanostructure and hydrophobic properties, worked as a shield to effectively thwarted liquid or bacterial penetration. Furthermore, accelerated wound closure, reduced inflammatory responses, and enhanced formation of hair follicles and blood vessels are achieved by the porous artificial skin covered on the surface of wound. Bilayer artificial skin integrates the advantages of nanofibers and freeze-drying porous materials to effectively replicate the protective properties of the epidermal layer of the skin, as well as the cell migration and tissue regeneration of the dermis. This bioabsorbable artificial skin demonstrates structural and functional comparability to real skin, which would advance the field of wound care through its multifaceted capabilities.


Asunto(s)
Quitosano , Nanofibras , Piel Artificial , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Quitosano/química , Quitosano/análogos & derivados , Porosidad , Animales , Nanofibras/química , Poliésteres/química , Poliésteres/farmacología , Gelatina/química , Antibacterianos/química , Antibacterianos/farmacología , Ratones , Staphylococcus aureus/efectos de los fármacos , Humanos
13.
Langmuir ; 29(32): 10213-22, 2013 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-23902279

RESUMEN

Many biomedical applications benefit from responsive polymer coatings. The properties of poly(dopamine) (PDA) films can be affected by codepositing dopamine (DA) with the temperature-responsive polymer poly(N-isopropylacrylamide) (pNiPAAm). We characterize the film assembly at 24 and 39 °C using DA and aminated or carboxylated pNiPAAm by a quartz crystal microbalance with dissipation monitoring (QCM-D), X-ray photoelectron spectroscopy, UV-vis, ellipsometry, and atomic force microscopy. It was found that pNiPAAm with both types of end groups are incorporated into the films. We then identified a temperature-dependent adsorption behavior of proteins and liposomes to these PDA and pNiPAAm containing coatings by QCM-D and optical microscopy. Finally, a difference in myoblast cell response was found when these cells were allowed to adhere to these coatings. Taken together, these fundamental findings considerably broaden the potential biomedical applications of PDA films due to the added temperature responsiveness.


Asunto(s)
Resinas Acrílicas/química , Indoles/química , Liposomas/química , Mioblastos/química , Polímeros/química , Proteínas/química , Temperatura , Animales , Adhesión Celular , Línea Celular , Ratones , Estructura Molecular , Mioblastos/citología , Tamaño de la Partícula , Propiedades de Superficie
14.
Int J Biol Macromol ; 226: 1579-1587, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36503823

RESUMEN

As a kind of bio-based polymer, poly (lactic acid) has potential application in fibers fields. Due to the weak nucleation ability, PLA crystallizes slowly and forms large spherulites during the forming process, which deteriorates the properties of PLA fibers. In this work, melt-spun method is employed for the fabrication of PLA/T composite fibers using succinate diphenyl dihydrazide (TMC-306) as the nucleating agent, and then the hot-drawing and heat setting is performed to the as-spun fibers. Compared with pure PLA fibers, PLA/T fibers show faster crystallization rate and improved performance due to the synergistic effect of heterogeneous nucleation and stress-induced crystallization. The characterization of non-isothermal crystallization behavior indicates that the peak crystallization temperature as well as crystallinity of PLA composites is increased to 121.5 °C and 36.78 % respectively by blending 0.3 wt% TMC-306. Meanwhile, the obtained PLA/0.3T composite fibers are highly crystallized and oriented at hot-drawing ratio of 2.4 folds and heat setting temperature of 100 °C, and the conformational stability is noticeably enhanced. Further, the tensile strength and storage modulus of PLA/0.3T composite fiber are 3.46 cN/dtex and 46,953 MPa respectively, which are increased by 42 % and 41 % compared with neat PLA fibers.


Asunto(s)
Poliésteres , Polímeros , Cristalización , Poliésteres/química , Polímeros/química , Temperatura
15.
Dent Mater ; 39(12): 1076-1084, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37827873

RESUMEN

OBJECTIVE: Graphene oxide (GO) is of great interest in dentistry as the functional filler, mainly owing to its ability to inhibit the formation of cariogenic bacteria and possess low cytotoxicity to different cells, such as human dental pulp cells, HeLa cells, etc. However, its typical brown color limits the practical application. METHODS: Here, the refractive-index-matched monodisperse SiO2 were used as the supporting substrates to synthesize GO-cladded SiO2 spheres (xSiO2 @ yGO) through a mild electrostatic self-assembly process, where x and y represent the amount of SiO2 and GO in the reaction mixture, respectively. The morphology and the optical performance of the obtained xSiO2 @ yGO particles were modulated by varying the mass ratio of SiO2 and GO (5:1, 10:1, 50:1, and 100:1). All developed hybrid particles were silanized and formulated with dimethacrylate-based resins. These were tested for curing depth, polymerization conversion, mechanical performance, in vitro cell viability, and antibacterial activity. RESULTS: Of all xSiO2 @ yGO materials, increasing the mass ratio to 100:1 made the 100SiO2 @GO particles appear light brown and possess the lowest light absorbance from 300 to 800 nm. The results of CIEL*a*b* system showed that all these hybrid particles exhibited obvious discoloration compared with SiO2 and GO, where 100SiO2 @GO possessed the smallest color difference. Furthermore, following the results of curing depth, polymerization conversion, and mechanical performance of dental composites, the optimal filler composition was 100SiO2 @GO at 5 wt% filler loading. The resultant 100SiO2 @GO-filled composite produced the highest flexural strength (115 ± 12 MPa) and the lowest bacterial concentration (6.7 × 108 CFU/mL) than those of the resin matrix (78 ± 11 MPa; 9.2 × 108 CFU/mL) and 5 wt% SiO2-filled composite (106 ± 9 MPa; 9.1 × 108 CFU/mL), respectively, without affecting in vitro cell viability. SIGNIFICANCE: The facile and mild synthesis of xSiO2 @ yGO hybrid particles provided a convenient way to tune their optical property. The optimal 100SiO2 @GO particles could be considered as the promising antibacterial filler to be applied in dental care and therapy.


Asunto(s)
Resinas Compuestas , Dióxido de Silicio , Humanos , Ensayo de Materiales , Resinas Compuestas/farmacología , Resinas Compuestas/química , Dióxido de Silicio/química , Propiedades de Superficie , Células HeLa , Antibacterianos , Materiales Dentales
16.
J Agric Food Chem ; 71(48): 18857-18864, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37994873

RESUMEN

Plant-derived biocompounds play a crucial role in the field of renewable materials due to their sustainability as they can be converted into monomers for polymerization, comparable to numerous monomers obtained from petroleum. In this work, betulin, a triterpene derivative with antibacterial properties obtained from birch tree bark, was esterified to produce two varieties of α,ω-diene derivatives with different lengths of methylene spacers. These derivatives were then copolymerized with 2,2'-(ethylenedioxy)diethanethiol using thiol-ene photopolymerization. We optimized and confirmed the polymerization parameters such as solvents, catalysts, and monomer concentrations. These analyses allowed for the obtainment of polysulfides with a high molar mass of up to 38.9 kg/mol under the optimized conditions. Furthermore, the polysulfides were converted into polysulfoxides by using a dilute hydrogen peroxide solution. Thermal analysis of the obtained polymers revealed excellent thermal stability (up to 300 °C) and tunable glass transition temperatures depending on their molar mass and composition. We successfully produced fibers with a diameter of approximately 3.9 µm by using the electrospinning technique. The morphology and hydrophobicity of the fibers were analyzed by using scanning electron microscopy and water contact angle analysis. Plant-derived polymeric fibers exhibited good cellular biocompatibility and broad-spectrum antibacterial activity, making them promising candidates for applications in fruit preservation.


Asunto(s)
Frutas , Triterpenos , Polímeros , Antibacterianos/farmacología
17.
ACS Biomater Sci Eng ; 9(5): 2706-2715, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37074009

RESUMEN

Biofilm formation on resin composite surfaces is associated with the occurrence of secondary caries around restorations. As a promising antibacterial nanomaterial, graphene oxide is effective to suppress the viability of the cariogenic bacteria Streptococcus mutans (S. mutans). However, GO naturally expresses brown, which limits its potential application in dentistry. In this work, ZnO nanorod-decorated graphene oxide (GOn@ZnO) particles were synthesized via a facile hydrothermal method, and their optical property was regulated by changing the amount of seeded GO (n value) in the microemulsion. Among all hybrid particles, GO3@ZnO exhibited a bright gray color and lowest UV absorbance and therefore was selected as an optimal functional filler to produce dental composites with different loadings (0.1, 0.5, 1, and 3 wt %). The effects of GO3@ZnO loading on light transmittance, polymerization conversion, mechanical property, in vitro cell viability, and antibacterial effect of dental composites were systematically explored. The results exhibited that the 0.5 wt % GO3@ZnO-filled composite demonstrated comparable degree of conversion (60 s), higher flexural strength and modulus, and similar cell viability to the control. This composite also effectively inhibited the growth of S. mutans, giving a significantly lower bacterial concentration (3.9 × 107 CFU/mL) than the unfilled resin (8.5 × 107 CFU/mL) and the 0.5 wt % GO-filled composite (6.6 × 107 CFU/mL), respectively. The introduction of GO3@ZnO in dental composites could be a promising strategy to prevent secondary caries and extend service life.


Asunto(s)
Óxido de Zinc , Óxido de Zinc/farmacología , Ensayo de Materiales , Antibacterianos/farmacología , Resinas Compuestas/farmacología , Bacterias
18.
Int J Biol Macromol ; 226: 646-659, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36521701

RESUMEN

Lignin remains the second abundant source of renewable carbon with an aromatic structure. However, most of the lignin is burnt directly for power generation, with an effective utilization rate of <2 %, making value addition on lignin an urgent requirement. From this perspective, preparation of lignin-based carbon fibers has been widely studied as an effective way to increase value addition on lignin. However, lignin species are diverse and complex in structure, and the pathway that enables changes in lignin structure during pretreatment, fiber formation, stabilization, and carbonization is still uncertain. In this review, we condense the common structural evolution route from the previous studies, which can serve as a guide towards engineered lignin carbon fibers with high performance properties.


Asunto(s)
Carbono , Lignina , Lignina/química , Fibra de Carbono , Carbono/química , Oxidación-Reducción
19.
Int J Biol Macromol ; 226: 670-678, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36521703

RESUMEN

The fabrication of bio-based copolyester fiber with adjustable crystallization, orientation structure and mechanical property still remains a great challenge. In this study, a series of copolyester fibers based on terephthalic acid (PTA), ethylene glycol (EG) and l-Lactide (L-LA) were prepared via melt copolymerization and spinning. The resultant PLA-co-PET (PETLA) fibers exhibited tunable structure and property due to the synergistic effects of chemical structure and drawing process. The chemical structure of PETLA was confirmed by NMR, FTIR and XRD, which suggested that the random degree of copolymer increased with LA content and the viscosity decreased with the increase of LA content. The crystallization behavior, melting characteristic, thermal stability and rheological property were investigated by DSC, TGA and rheometer, the results indicated that all the PETLA exhibited the crystallization capacity, melting temperature and thermal stability were slightly affected by LA segment. The synergistic effects of LA segment and spinning process on PETLA structure and property were analyzed by WAXD and SAXS. The breaking strength of PETLA fibers dropped from 5.3 cN/dtex of PET to 2.8 cN/dtex of PET85LA15, which still met the requirements of most textile applications. Therefore, our work presented a feasible approach to prepare bio-based polyester fibers with tunable property.


Asunto(s)
Poliésteres , Polímeros , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Poliésteres/química , Cristalización
20.
Int J Biol Macromol ; 233: 123588, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36764341

RESUMEN

Converting lignin into high value-added products is essential to reduce our dependence on petroleum resources and protect our environment. In this work, TiO2 and g-C3N4 are loaded in the lignin-derived carbon nanofibers (LCNFs) and an efficient LCNFs-based photocatalytic material (TiO2/g-C3N4@LCNFs) is developed. The spinnability of lignin solution, the chemical structure and morphology of the LCNFs, and the catalytic degradation property of the TiO2/g-C3N4@LCNFs for Rhodamine B (RhB) are systematically investigated. The TiO2/g-C3N4@LCNFs achieve a 92.76 % degradation rate of RhB under UV-vis irradiation, which is close to or higher than most reported carbon fiber-based photocatalysts. The excellent degradation property of the photocatalysts can be ascribed to the synergy of TiO2 and g-C3N4, which improves the excitation efficiency of electron and hole, and prolongs the lifetime of electron-hole pairs. We envision that our work will provide some guidance for the development of efficient photocatalysts based on biomass-derived fiber materials.


Asunto(s)
Carbono , Nanofibras , Lignina , Titanio/química
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