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1.
ACS Appl Mater Interfaces ; 12(21): 24370-24379, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32368896

RESUMO

Easy and rapid continuous large-scale industrial production of transparent visualized cutaneous wound healing dressing from natural polymers is very worth studying in medical natural polymer materials and multifunction gauze dressing design fields. In this work, superclear, porous cellulose membranes (CMs) with chitosan-coated nanofibers were fabricated using a simple, one-step electrostatic spinning technology and evaluated as potential wound dressings. First, the pure CMs were dissolved by a simple physical method, and then, the membranes were regenerated in an acidic coagulation bath by the casting method. The chitosan solution was polarized into nanofibers and formed a continuous fiber mat on CMs because of the charge repulsion between molecules. The prepared chitosan-coated CMs (CM-CS) were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, tensile tests, and so forth. The results indicated that CM-CS showed high wettability, hydrophilicity, and gas permeability, in addition to excellent light transmittance and mechanical compliance. Cell cytotoxicity and morphology assay and antibacterial activity against Escherichia coli and Staphylococcus aureus were also studied. They exhibited good biocompatibility and antibacterial activity of CM-CS. Moreover, evaluation of an in vivo wound healing model in mice revealed that CM-CS had a good effect in promoting wound healing. This work provided an easy and rapid continuous large-scale industrial design strategy for natural bioresource-based wound dressing materials, which could act as potential wound dressings for clinical use.

2.
Mikrochim Acta ; 187(6): 341, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444888

RESUMO

N-Doped silicon quantum dots (N-SiQD) were synthesized using N-[3-(trimethoxysily)propyl]-ethylenediamine and citric acid as silicon source and reduction agent, respectively. The N-SiQD shows a strong blue fluorescence with a high quantum yield of about 53%. It is found that a selective static quenching process occurs between N-SiQDs and Cu2+. Glyphosate can inhibit this phenomenon and trigger the rapid fluorescence enhancement of the quenched N-SiQDs/Cu2+ system due to the specific interaction between Cu2+ and glyphosate. With such a design, a turn-on fluorescent nanoprobe based on N-SiQD/Cu2+ system was established for rapid determination of glyphosate. The determination signal of N-SiQD/Cu2+ was measured at the optimum emission wavelength of 460 nm after excitation at 360 nm. Under optimal conditions, the turn-on nanoprobe showed a linear relationship between fluorescent response and glyphosate concentrations in the range 0.1 to 1 µg mL-1. The limit of determination was calculated to 7.8 ng mL-1 (3σ/S). Satisfactory recoveries were obtained in the determination of spiked water samples, indicating the potential use for environmental monitoring. Graphical abstract Schematic representation of N-SiQD/Cu2+ system for glyphosate determination. Fluorescence quenching of N-SiQDs induced by copper ions and the succedent fluorescent "turn on" triggered by glyphosate.

3.
Mol Immunol ; 122: 124-131, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344244

RESUMO

Thousand and one amino acid kinase 1 (TAOK1) is a member of Ste20-like kinases, but its function in regulating inflammatory responses remains largely unknown. In this study, we identify TAOK1 as a positive regulator of TLR4-triggered inflammatory responses in macrophages. TAOK1 increases LPS-induced production of pro-inflammatory cytokine such as IL-6, TNF-α and IL12p40 in macrophages. TAOK1 deficient mice showed decreased susceptibility to endotoxin shock, with less pro-inflammatory cytokine production than control mice. TAOK1 promotes LPS-induced activation of ERK1/2 by constitutively interacting with TRAF6 and TPL2. These finding unravel the important role of TAOK1 as a positive regulator of TLR4-induced inflammatory responses.

4.
Ophthalmic Res ; 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32305986

RESUMO

PURPOSE: GATA4 has emerged as a novel regulator that plays a critical role in mediating senescence. However, the role of GATA4 in age-related cataract (ARC), the leading cause of visual impairment, requires further elucidation. METHODS: Expression level of GATA4 was measured by qRT-PCR and Capillary Western Immunoassay (WES). MTT assay, EdU assay, Rhodamine 123/ Hoechst and Calcein-AM/ propidium iodide double staining were used to investigate the role of GATA4 in the viability, proliferation and apoptosis in cultured human lens epithelial cells (HLECs). RESULTS: HLECs were subjected to three models, including prolonged exposure to low dose of H2O2, UVB radiation and mild heating, to simulate senescence and apoptosis. GATA4 expression was significantly increased in these models in a time- and dose- dependent manner. Overexpression of GATA4 reduced cell viability, accelerated apoptosis development and reduced the proliferation of HLECs. Furthermore, the expression of GATA4 from ARC was up-regulated at both mRNA and protein levels compared with the clear lenses. CONCLUSIONS: GATA4 is up regulated in all three models of HLECs in vitro and the cells from ARC lenses in vivo. Up-regulation of GATA4 mediates HLECs dysfunction. GATA4-mediated effects in HLECs would provide a novel insight into the pathogenesis of ARC.

5.
Food Chem ; 319: 126232, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32197213

RESUMO

Yeast ß-glucan (YG) adsorbs off-odor in silver carp mince due to its more porous structure. To explore adsorption behavior and mechanism, adsorption kinetics and thermodynamics of YG for 3 off-odor compounds (hexanal, 1-octen-3-ol and nonanal) were investigated by pseudo-first/second-order models and isothermal equations (Langmuir, Freundlich and Redlich-Peterson). Kinetic experiments indicated adsorption process followed pseudo-first-order model. Adsorption isotherms indicated 3 off-odors could easily be adsorbed by YG and adsorption capacity was in the order of 1-octene-3-ol > hexanal > nonanal. Thermodynamic result suggested adsorption of 3 off-odors by YG was endothermic and spontaneous, and was driven predominantly by physisorption and hydrophobic interaction. Consequently, the contents of 3 off-odors that released from mince/YG complex decreased by 22.8%, 29.9%, and 24.5% (p < 0.05), respectively, compared with those from mince without YG. Therefore, the addition of YG enhanced the binding capability to off-odors, thus reducing the release of off-odor from silver carp mince.

6.
Bioresour Technol ; 302: 122812, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32007848

RESUMO

In this work, two plant wastes were reused to fabricate the homogeneous 3D micro-nano porous structured humic acid/cellulose nanocomposite beads (IHA@CB) embedded with insoluble humic acid (IHA) particles. The subtle synthesis method attributed to the homogenous distribution of IHA particles in the cellulose matrix and improved the adsorption performance of IHA@CB for low concentration ciprofloxacin in water. Physical and chemical properties of the beads were characterized by SEM, EDX, XRD, FTIR, and the adsorption process of ciprofloxacin was studied by isotherm, kinetic and dynamic adsorption experiments. The maximum adsorption capacity of IHA@CB on CPX reached 10.87 mg g-1 under 318 K. The dynamic experiments were conducted by adjusting bed height, flow rate, initial concentration and pH values, and the regeneration experiments proved the adsorbent exhibited good repeatability. The adsorption mechanism was revealed that CPX was adsorbed by IHA@CB mainly through cation exchange.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Adsorção , Celulose , Ciprofloxacino , Concentração de Íons de Hidrogênio , Cinética , Água
7.
Carbohydr Polym ; 231: 115694, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888800

RESUMO

Cellulose-based photocatalysts of supported nanoparticles feature high photocatalytic activity but their facile construction and photocatalytic mechanism exploration are highly challenging. Herein, a simple structural design principle and synergistic properties of 3-layered porous cellulose-based membranes are used for catalytic degradation of Rhodamine B in an aqua system. The 3-layered Au-TiO2 cellulose membranes were fabricated through the tape method and the suction filtration process. The composite membranes with strong redox ability, high charge-separation efficiency, and wide absorption range could stimulate the solar-driven plasma evaporation of Au nanoparticles and the photocatalytic function of TiO2 nanoparticles simultaneously. As characterized by Scanning Electron Microscopy, well-defined Au nanoparticles with an average size of 18.24 ±â€¯3.17 nm were uniformly distributed on the TiO2-CM surface. Compared with TiO2-CM, TiO2-Au-CM showed better catalytic degradation of organic dye. This work demonstrated that a simple strategy design of Au-TiO2-CM could efficiently enhance the photocatalytic activity for the degradation of dyes in water.

8.
Int J Biol Macromol ; 149: 93-100, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31931058

RESUMO

Amoxicillin in the municipal water system needs to be removed due to the toxicity towards creatures. In this work, Mg-Al LDH/cellulose nanocomposite beads (LDH@CB) were synthesized by an in situ coprecipitation procedure and were used as novel adsorbents for amoxicillin removal in the aqueous phase. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), The specific surface area test (BET), scanning electron microscopy (SEM), ζ potential, X-ray electron energy (XPS) were employed to confirm the success load of LDH onto CB. The large specific surface area (76.46 m2 g-1), high water content (92.05%) and high porosity (94.75%) of LDH@CB made the adsorbent suitable in water treatment. The adsorption process was kinetically fitted with the pseudo second-order kinetic model while isothermally fitted with the Freundlich isotherm model. It was found that the maximum adsorption capacity of LDH@CB qm was 138.3 mg g-1. Meanwhile, the results from XPS and ζ potentials revealed the AMX removal mechanism: Under natural pH conditions, AMX was negatively charged and LDH@CB was positively charged, the contaminant and the adsorbent were linked by electrostatic interaction through OCO⋯M (Mg/Al). These results showed that the adsorbent design method had a wide application prospect in the water purification field.

9.
J Hazard Mater ; 384: 121195, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585281

RESUMO

Due to strong activity, it is very difficult to remove low concentrations of bromide in medical wastewater by traditional method, thus highly effective and greener adsorbents should be utilized to design. In this work, the cellulose beads (CBs) were modified by the TEMPO-mediated oxidation and then bonded with Fe3+ to fabricate Fe(III)-complexed carboxylated cellulose beads (Fe-CCBs) adsorbents. Structure and properties of Fe-CCBs were analyzed using Energy dispersive spectrum (EDS), Scanning electron microscopy (SEM), Fourier transform infrared spectrum (FT-IR), total acidity and basicity groups, X-ray diffraction (XRD), N2 adsorption-desorption and Thermogravimetric (TGA). Moreover, batch adsorption experiments showed that the adsorption of Br- was better consistent with general-order kinetic model and Liu isotherm model, which could also further clarify the adsorption process mechanism. Meanwhile, the results revealed that removal of Br- was a spontaneous exothermic process and was more suitable to be carried out under neutral or acidic conditions. Furthermore, the mechanism of adsorption behavior of bromide ions on Fe-CCBs was based on a combination of electrostatic attraction and outer-sphere complexation. The results of this study can provide guidance for the design of novel material adsorbents and the removal of harmful anions from aqueous solutions.

10.
Int J Biol Macromol ; 142: 404-411, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626821

RESUMO

In this work, the coagulation mechanism of the cellulose/metal nanohybrids and the binding mode with Cr (VI) are deeply described. Nanohybrids with 3D porous networks were prepared from cellulose/Fe2O3-SO3H solutions through a simple one-step coagulation process in NaCl aqueous solutions. The structure and properties of nanohybrids were characterized by SEM, EDS, XRD, FTIR, and XPS. The cellulose/metal nanohybrids have a langmuir maximum adsorption capacity of 11.46 mg/g. The dissolved metal nanoparticles could form strong hydrogen bonding with cellulose by breaking the intermolecular hydrogen bonds between the polymer molecules. The porous networks of cellulose/metal nanohybrids provided multiple adsorption sites for Cr2O72- anion through FeO…Cr interactions. The cooperation between cellulose and Fe2O3-SO3H nanoparticles makes the hybrids exhibiting a satisfactory selectivity and affinity for Cr (VI). The cellulose/metal nanohybrids selectively interacted with Cr2O72- via Fe atom from Fe2O3 and oxygen atom from SO3- groups. The Cr (VI) adsorption occurred via a two-step process, the first of them was the initial adsorption of Cr2O72- on cellulose/metal nanohybrids surface, followed by the rearrangement of Cr2O72- molecules and the consecutive growth of Cr2O72- aggregate layers.

11.
Bioconjug Chem ; 31(3): 663-672, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31884782

RESUMO

Light-activated phototherapy, including photothermal and photodynamic therapy, has become a new way for spatiotemporal control and noninvasive treatment of cancer. In this study, two new organic porphyrin molecules (NI-Por and NI-ZnPor) with donor (D)-acceptor (A) structure were designed and synthesized. The donor-acceptor pairs facilitated the intermolecular electron transfer, resulting in the enhancement of near-infrared (NIR) absorbance and nonradiative heat generation. After self-assembling, the nanoparticles were formed with the size around 60 nm. Relative to that of organic molecules, the absorption of NI-Por NPs and NI-ZnPor NPs broadened and red-shifted to the near-infrared region. Moreover, the porphyrin-containing nanoparticles can generate heat and reactive oxygen species (ROS) simultaneously induced by a single laser (635 nm). The intracellular reactive oxygen species production of NI-Por NPs and NI-ZnPor NPs was confirmed using DCFH-DA as an indicator. Furthermore, the localization of NI-Por NP and NI-ZnPor NP in HeLa cells was verified by fluorescence confocal laser microscopy. The photocytoxicity of two nanoparticles against HeLa cells was evaluated through the CCK-8 method. The IC50 of NI-Por NPs and NI-ZnPor NPs upon 635 nm laser irradiation was calculated to be 6.92 µg/mL and 5.86 µg/mL, respectively. Furthermore, the PDT/PTT synergistic effect of NPs under a 635 nm laser was verified through different treatment groups in vitro. All these results demonstrated that the as-prepared porphyrin-based nanoparticles are promising nanoagents for PDT/PTT in clinic.

12.
Molecules ; 24(24)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835770

RESUMO

Adsorption and desorption behaviors of tetracycline hydrochloride by activated carbon-based adsorbents derived from sugar cane bagasse modified with ZnCl2 were investigated. The activated carbon was tested by SEM, EDX, BET, XRD, FTIR, and XPS. This activated carbon exhibited a high BET surface area of 831 m2 g-1 with the average pore diameter and pore volume reaching 2.52 nm and 0.45 m3 g-1, respectively. The batch experimental results can be described by Freundlich equation, pseudo-second-order kinetics, and the intraparticle diffusion model, while the maximum adsorption capacity reached 239.6 mg g-1 under 318 K. The effects of flow rate, bed height, initial concentration, and temperature were studied in fixed bed adsorption experiments, and adsorption data were fitted with six dynamic adsorption models. The results of characterizations and the batch experiments were analyzed to study the adsorption and desorption mechanisms. Tetracycline hydrochloride and activated carbon were bonded together by π-π interactions and cation-π bonds. Ethanol was used as an eluent which bonded with 10 hydrogen bond acceptors on tetracycline hydrochloride to form a complex by hydrogen bonding to achieve recycling.

13.
Anal Chem ; 91(24): 15461-15468, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31710204

RESUMO

High-purity cellulose membranes prepared via a green pathway were used to attempt to enhance their performance of glucose detection compared with that of traditional filter paper. In this work, cellulose-based strips (CBS) for the low concentration of glucose detection have been designed based on a fast, sensitive, and easy enzyme colorimetric assay from porous and high-purity cellulose membranes (CM). Different from the traditional paper-based sensors that were made of commercially available filter paper, the cellulose-based membranes matrix was fabricated by a "green" route in that cellulose was dissolved in an aqueous NaOH/urea solution, and then modified by the sodium periodate oxidation method to immobilize the glucose oxidase (GOX) and horseradish peroxidase (HRP) with Schiff-base reaction. The structure and properties of CM and CBS were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray mapping (EDS), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), etc. SEM images showed a porous, interpenetrating structure of CM, which benefited the enzyme immobilization and enzymatic reaction. When glucose solution was dropped onto the CBS, the color change from colorless to blue was only 5 min. The limit of detection (LOD) is 0.45 mM in the linear range of glucose from 1 to 11 mM. Moreover, the CBS had also been successfully used for glucose determination in real urine samples, and the color changes can be easily recorded by a simple camera to achieve the semiquantitative detection of glucose. This work provided a new design strategy for the cellulose-based functional materials which could be applied in biosensors, drug carriers, and biomedicine.

14.
Anal Chim Acta ; 1089: 66-77, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31627820

RESUMO

The dehydration reaction of tetraamino porphyrin and 4,4'-biphenyldicarboxaldehyde was performed for the synthesis of a novel covalent organic framework (COF), which was decorated on magnetic Fe3O4 to obtain core-shell structured Fe3O4@COFs nanospheres for the first time, for effective extraction and enrichment of sulfonamides (SAs). The morphology and structure of the synthesized nanospheres were characterized through various methods. The extraction conditions for six SAs including sulfadiazine, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfamethoxazole, sulfadimethoxine were systematically optimized. Fe3O4@COFs nanospheres were evaluated for magnetic solid-phase extraction. By coupling with high-performance liquid chromatography, a facile and sensitive method was established for the quantitation analysis of six SAs. The method showed good linearity ranging from 1 to 500 ng mL-1 with R2 > 0.99, high sensitivity with LODs in the range of 0.2-1 ng mL-1, and high precision with RSDs≤6.3%. This method was further applied into determination of SAs in environmental water and food samples, with recoveries in the range of 65.3%-107.3% and RSDs≤6.7%. These successful applications suggest that the core-shell structured Fe3O4@COFs nanospheres could be used as a potential adsorbent for efficient extraction and analysis of trace SAs.


Assuntos
Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Porfirinas/química , Sulfonamidas/análise , Poluentes Químicos da Água/análise , Adsorção , Animais , Galinhas , Lagos/análise , Limite de Detecção , Estruturas Metalorgânicas/síntese química , Leite/química , Penaeidae , Porfirinas/síntese química , Frutos do Mar/análise , Extração em Fase Sólida/métodos
15.
Carbohydr Polym ; 223: 115065, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426953

RESUMO

Probiotics are believed to provide benefits to human health; however, a good storage stability is the prerequisite for the probiotic products making function. Herein, we reported a pathway to fabricate the Ca-alginate/cryoprotectants/cellulose composite (ACFP) capsules to protect L. plantarum cells, which showed the minimal loss of viability during the vacuum freeze-drying process. The trehalose and whey protein isolate (WPI) ingredients in the cryoprotectants prolonged the dissolution time of Ca-alginate shell, which contributed to controlling the release of cells in the desired region. The dry ACFP capsules exhibited gradual release of L. plantarum cells in simulated intestinal fluid (SIF), 2.6 × 106 cfu/mL at 210 min. In addition, 0.1 g of the dry ACFP capsules showed the viable release amount of 3.3 × 106 cfu/mL after the storage of 160 days at 4 °C. The promising results provided a strategy of encapsulating probiotic cells to achieve long-term storage stability and enhanced controlled release behavior in simulated intestinal fluid in the meantime.


Assuntos
Alginatos/química , Celulose/química , Lactobacillus plantarum , Probióticos , Cápsulas/química , Crioprotetores/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Glicerol/química , Viabilidade Microbiana/efeitos dos fármacos , Trealose/química , Proteínas do Soro do Leite/química
16.
Colloids Surf B Biointerfaces ; 182: 110345, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31299540

RESUMO

Two new porphyrin-based organic compounds (Por and ZnPor) were synthesized by introducing hydrophilic polyethylene glycol chains and pentafluorobenzene moieties onto the parent porphyrin structure. After self-assembling into nanoparticles, the absorption spectrum of (Zn)Por NPs broadened and red-shifted to some extent, relative to that of organic molecules. Meanwhile, the fluorescence of organic molecule nanoparticles was quenched significantly, which facilitated the nonradiative thermal generation for potential applications in photothermal cancer therapy. Por NPs and ZnPor NPs presented spherical structure with average diameter about 100 nm, endowing them with tumor targeting properties based on the enhanced permeability and retention (EPR) effect. Due to the heavy atom effect, ZnPor NPs presented the higher efficiency of ROS generation than that of Por NPs. In contrast, Por NPs exhibited the better photothermal effect relative to that of ZnPor NPs under irradiation of a 635-nm laser. The photothermal conversion efficiency of Por NPs was calculated to be 16.34%. The in vitro experiments suggested that Por NPs and ZnPor NPs could enter tumor cells efficiently with good biocompatibility and exhibited high photocytotoxicity with IC50 of 7.3 µg/mL and 3.0 µg/mL, respectively. Thus, the as-prepared porphyrin nanomaterials can be used as potential photosensitizers for cancer photodynamic/photothermal synergistic therapy in vivo, benefiting from their good biocompatibility, strong near-infrared absorption, and high photodynamic and photothermal effects.


Assuntos
Terapia Combinada/métodos , Complexos de Coordenação/química , Nanopartículas/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Porfirinas/química , Benzaldeídos/química , Benzenossulfonatos/química , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Terapia com Luz de Baixa Intensidade/métodos , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis/química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Zinco/química
17.
Int J Biol Macromol ; 139: 793-800, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31362024

RESUMO

Since effective shielding of X-rays was required in medical, aviation and nuclear fields, a novel X-ray shielding BaSO4/cellulose nanocomposite membrane (BSCM) material with porous transparent structure has been designed. The effects of carboxylated nano-BaSO4 (BS) addition on the physical and morphological properties of the cellulose membrane (CM) were investigated. Meanwhile, the influence of X-ray shielding capacity was studied by different layers of composite membranes and the shielding mechanism of the X-ray was also discussed. Scanning electron microscopy (SEM) images displayed the aggregations of BS in the cellulose surface. Fourier transform infrared spectroscopy (FTIR) showed that the incorporation of BS into CM caused molecular interactions between CM and BS. Brunauer-Emmett-Teller (BET) indicated that the load of BS contributed little to the specific surface area and pore size. Meanwhile, the water vapor transmission rates (WVTR) also stayed at the same level before and after the binding of BS. The swelling ratios, weight loss ratios and mechanical property were decreased along with the addition of BS. The radiation shielding ability was enhanced. Therefore, this work was regarded as a possible example that the BSCM was designed as X-ray radiation shielding material or sandwich filler material in the implication of radiation shielding glass.

18.
Environ Sci Pollut Res Int ; 26(27): 27677-27686, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31338764

RESUMO

Increasing degradation of amoxicillin in water by low-cost advanced functional activated carbon-based materials derived from bagasse is an effective and economic way to remove the antibiotic residue pollutant and for high-valued utilization and transformation of plant wastes. In this work, bagasse was pyrolyzed and Zn2+ was activated for designing a high-efficiency bagasse-based activated carbon, which was characterized by FTIR, XRD, XPS, SEM, EDS, and ζ potential analyses. These analyses illustrated the mechanism of amoxicillin degradation, and microscale zero-valent zinc in bagasse-based activated carbon has a key role in amoxicillin degradation. Amoxicillin was broken down by reductive degraded radicals, which were produced by microscale zero-valent zinc corrosion in water. After the amoxicillin degradation, the byproduct of zinc hydroxide being adsorbed onto the used bagasse-based activated carbon can provide possibility of sustainable regeneration. Mass spectra analysis illustrated the main degradation products of amoxicillin. The kinetic experiments were adopted to observe the process of amoxicillin degradation, followed by the pseudo-first-order kinetic model. The isotherm experiments demonstrated that the maximum amoxicillin degradation capacity of bagasse-based activated carbon was about 46 mg g-1. The bagasse wastes were used as carbon source to design potential advanced activated carbon materials for increasing degradation of amoxicillin in water.


Assuntos
Amoxicilina/análise , Carvão Vegetal/química , Hidróxidos/química , Poluentes Químicos da Água/análise , Compostos de Zinco/química , Zinco/química , Adsorção , Amoxicilina/química , Celulose , Cinética , Água , Poluentes Químicos da Água/química , Purificação da Água
19.
ACS Appl Mater Interfaces ; 11(24): 21408-21416, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31120723

RESUMO

Near-infrared (NIR)-absorbing organic nanoparticles (ONPs) are emerging candidates for "one-for-all" theranostic nanomaterials with considerations of safety and formulation in mind. However, facile fabrication methods and improvements in the photothermal conversion efficiency (PCE) and photostability are likely needed before a clinically viable set of candidates emerges. Herein, a new organic compound, [porphyrin-diketopyrrolopyrrole (Por-DPP)] with the donor-acceptor structure was synthesized, where porphyrin was used as a donor unit while diketopyrrolopyrrole was used as an acceptor unit. Por-DPP exhibited efficient absorption extending from visible to NIR regions. After self-assembling into nanoparticles (NPs) (∼120 nm), the absorption spectrum of Por-DPP NPs broadened and red-shifted to some extent, relative to that of organic molecules. Furthermore, the architecture of NPs enhanced the acceptor-donor structure, leading to emission quenching and facilitating nonradiative thermal generation. The PCE of Por-DPP NPs was measured and calculated to be 62.5%, higher than most of ONPs. Under 808 nm laser irradiation, the Por-DPP NPs possessed a distinct photothermal therapy (PTT) effect in vitro and can damage cancer cells efficiently in vivo without significant side effects after phototherapy. Thus, the small-molecule porphyrin-based ONPs with high PCE demonstrated promising application in photoacoustic imaging-guided PTT.


Assuntos
Nanopartículas/química , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Porfirinas/química , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Porfirinas/farmacologia , Nanomedicina Teranóstica/métodos
20.
Polymers (Basel) ; 11(5)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31052390

RESUMO

It is challenging to prepare polyurethane bioplastics from renewable resources in a sustainable world. In this work, polyurethane nanocomposite bioplastics are fabricated by blending up to 80 wt % of soy-based polyol and petrochemical polyol with hydroxyl-functionalized multiwalled carbon nanotubes (MWCNTs-OH). The scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR) analyses reveal homogeneous dispersion of the MWCNTs-OH in the matrix, as well as interaction or reaction of MWCNTs-OH with the matrix or polymeric methylene diphenyl diisocyanate (pMDI) in forming the organic-inorganic hybrid bioplastic with a three-dimensional (3D) macromolecule network structure. Mechanical properties and electrical conductivity are remarkably enhanced with the increase of the multiwalled carbon nanotube (MWCNTs) loading. Dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) results show that the bioplastics with MWCNTs-OH have a better thermal stability compared with the bioplastics without MWCNTs-OH. The composition of the nanocomposites, which defines the characteristics of the material and its thermal and electrical conductivity properties, can be precisely controlled by simply varying the concentration of MWCNTs-OH in the polyol mixture solution.

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