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1.
Cellulose (Lond) ; : 1-13, 2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37360890

RESUMO

Nitrocellulose (NC) membrane was fabricated and tested for its potential use in various paper-based biosensors for use in point-of-care testing. However, contemporary technologies are complex, expensive, non-scalable, limited by conditions, and beset with potentially adverse effects on the environment. Herein, we proposed a simple, cost-effective, scalable technology to prepare nitrocellulose/cotton fiber (NC/CF) composite membranes. The NC/CF composite membranes with a diameter of 20 cm were fabricated in 15 min using papermaking technology, which contributes to scalability in the large-scale production of these composites. Compared with existing commercial NC membranes, the NC/CF composite membrane is characterized by small pore size (3.59 ± 0.19 µm), low flow rate (156 ± 55 s/40 mm), high dry strength (up to 4.04 MPa), and wet strength (up to 0.13 MPa), adjustable hydrophilic-hydrophobic (contact angles ranged from 29 ± 4.6 to 82.8 ± 2.4°), the good adsorption capacity of protein (up to 91.92 ± 0.07 µg). After lateral flow assays (LFAs) detection, the limit of detection is 1 nM, which is similar to commercial NC membrane (Sartorius CN 140). We envision the NC/CF composite membrane as a promising material for paper-based biosensors of point-of-care testing applications.

2.
Entropy (Basel) ; 25(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37628150

RESUMO

In the era of the popularization of the Internet of Things (IOT), analyzing people's daily life behavior through the data collected by devices is an important method to mine potential daily requirements. The network method is an important means to analyze the relationship between people's daily behaviors, while the mainstream first-order network (FON) method ignores the high-order dependencies between daily behaviors. A higher-order dependency network (HON) can more accurately mine the requirements by considering higher-order dependencies. Firstly, our work adopts indoor daily behavior sequences obtained by video behavior detection, extracts higher-order dependency rules from behavior sequences, and rewires an HON. Secondly, an HON is used for the RandomWalk algorithm. On this basis, research on vital node identification and community detection is carried out. Finally, results on behavioral datasets show that, compared with FONs, HONs can significantly improve the accuracy of random walk, improve the identification of vital nodes, and we find that a node can belong to multiple communities. Our work improves the performance of user behavior analysis and thus benefits the mining of user requirements, which can be used to personalized recommendations and product improvements, and eventually achieve higher commercial profits.

3.
Environ Monit Assess ; 192(9): 585, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32809133

RESUMO

Wetlands are carbon pools for terrestrial ecosystems and play an important role in the global carbon cycle. The Nanhui tidal flat is located at the Yangtze River estuary and has been disturbed by various human activities. However, the effect of human activities on the carbon accumulation capability and carbon storage of wetlands in the Nanhui tidal flat is poorly understood. In this study, the annual carbon accumulation capability and carbon storage of three types of Spartina alterniflora Loisel. wetlands in the Nanhui tidal flat, which were defined as a natural wetland, silt-promoting wetland, and artificial restored wetland, were evaluated by analyzing the plant carbon fixation capability, soil carbon emissions, and soil organic carbon (SOC) density. The results showed that the three wetlands all had a carbon sink effect and the natural wetland, artificial restored wetland, and silt-promoting wetland annually accumulated 7.94, 7.14, and 6.33 kg m-2 CO2, respectively. The existing SOC density in the subsurface soil (0-40 cm) in the natural wetland, silt-promoting wetland, and artificial restored wetland was 23.26, 17.95, and 12.21 kg m-2 CO2, respectively. The natural wetland, with no human disturbance, had a longer duration of waterlogging and greater tidal nutrition inputs than the other wetlands, resulting in a higher plant biomass and lower soil respiration (SR). It therefore had the strongest carbon accumulation capability and highest SOC storage.


Assuntos
Estuários , Áreas Alagadas , Carbono/análise , China , Ecossistema , Monitoramento Ambiental , Rios , Solo
4.
Macromol Rapid Commun ; 40(17): e1900096, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31111979

RESUMO

Molecular imprinting is an approach of generating imprinting cavities in polymer structures that are compatible with the target molecules. The cavities have memory for shape and chemical recognition, similar to the recognition mechanism of antigen-antibody in organisms. Their structures are also called biomimetic receptors or synthetic receptors. Owing to the excellent selectivity and unique structural predictability of molecularly imprinted materials (MIMs), practical MIMs have become a rapidly evolving research area providing key factors for understanding separation, recognition, and regenerative properties toward biological small molecules to biomacromolecules, even cell and microorganism. In this review, the characteristics, morphologies, and applicability of currently popular carrier materials for molecular imprinting, especially the fundamental role of hydrogels, porous materials, hierarchical nanoparticles, and 2D materials in the separation and recognition of biological templates are discussed. Moreover, through a series of case studies, emphasis is given on introducing imprinting strategies for biological templates with different molecular scales. In particular, the differences and connections between small molecular imprinting (bulk imprinting, "dummy" template imprinting, etc.), large molecular imprinting (surface imprinting, interfacial imprinting, etc.), and cell imprinting strategies are demonstrated in detail. Finally, future research directions are provided.


Assuntos
Hidrogéis/química , Substâncias Macromoleculares/química , Impressão Molecular/métodos , Nanopartículas/química , Polímeros/química , Porosidade
5.
J Environ Manage ; 249: 109371, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404853

RESUMO

Point bar areas around lakes can provide ecological service functions. For example, plants growing on point bars absorb and remove nutrients from the soil and water. However, if the point-bar plants are unregulated, in the fall and winter, plant debris will decompose, releasing nutrients that then enter the water body and cause eutrophication. Therefore, any harvesting should be managed. But how to harvest plants and how often to harvest them, and there is little research on these. In this study, the point bar at Qingcaosha Reservoir was used to study the effects of three plant harvesting modes (M1: unharvested; M2: one harvest in the fall; and M3: one harvest in summer and one in the fall) on the removal of nitrogen (N) from point-bar soil. The largest amount of N was removed by the plants when the M3 mode was used (26.93 g/m2). However, the M2 mode removed the most N from the soil during the plant growth season (81.62 g/m2), which implied that the nitrification and denitrification effects of soil microorganisms make the largest contribution to N removal from this point-bar soil. The nitrification and denitrification activity of microorganisms was higher for M2 than for M1 and M3 in the following year. Additionally, summer harvesting (M3) had a negative effect on nitrification efficiency in the current season because anaerobic bacteria in the soil significantly increased and nitrifying bacteria significantly decreased after harvesting. However, after a period of recovery, the number of microbial nitrifiers increased again and nitrification activity rose in the following year. The reduction in oxygen supply after harvesting may be the main reason for low nitrification in the current season, but it was beneficial to nitrification and denitrification in the following year because there was luxuriant plant growth. Therefore, when considering both the current season and the following year, harvesting should not be too frequent and one harvest in the fall (M2) led to the largest removal of N from the soil.


Assuntos
Lagos , Nitrogênio , Desnitrificação , Nitrificação , Solo
6.
Environ Monit Assess ; 191(12): 750, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728745

RESUMO

Wetlands are important carbon (C) pools for terrestrial ecosystems, and C stored in different types of wetlands accounts for about 30% of total terrestrial C. As one of the most important ecological barriers in Shanghai, with functions of climate regulation, interception, and purification, and as a C sink, the Jiuduansha wetland has received research attention. However, little research has been done on the spatial differences in amount of average annual net C accumulation and C storage of each shoal: Jiangya Nansha, Shangsha, and Zhongxiasha. In this study, plant biomass, plant organic C, soil respiration, soil organic C content, and soil bulk density of different vegetation zones in the three shoals were analyzed to determine the spatial variability of annual net C accumulation capability and soil organic C storage of the Jiuduansha wetland. The results showed that the Zhongxiasha shoal played the most important role as a C sink, and it accumulated 77,839.44 t organic C per year. Regarding the annual C accumulation capacity per unit area, the Phragmites communis zone was higher than for all other vegetation zones, indicating that P. communis had the greatest C accumulation capacity. 7835.38 t, 46,827.41 t, and 173,623.1 t of organic C were stored in the Jiangya Nansha, Shangsha, and Zhongxiasha shoals, respectively. The C storage in soil was closely related to annual C accumulation, and there were two main reasons for the difference of spatial pattern of annual C accumulation: biomass and properties of plants and the properties of tidal water.


Assuntos
Carbono/análise , Monitoramento Ambiental/métodos , Poaceae/química , Rios/química , Solo/química , Biomassa , China , Ecossistema , Estuários , Plantas , Áreas Alagadas
7.
J Sep Sci ; 39(10): 1863-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26991761

RESUMO

A novel l-phenylalanine molecularly imprinted solid-phase extraction sorbent was synthesized by the combination of Pickering emulsion polymerization and ion-pair dummy template imprinting. Compared to other polymerization methods, the molecularly imprinted polymers thus prepared exhibit a high specific surface, large pore diameter, and appropriate particle size. The key parameters for solid-phase extraction were optimized, and the result indicated that the molecularly imprinted polymer thus prepared exhibits a good recovery of 98.9% for l-phenylalanine. Under the optimized conditions of the procedure, an analytical method for l-phenylalanine was well established. By comparing the performance of the molecularly imprinted polymer and a commercial reverse-phase silica gel, the obtained molecularly imprinted polymer as an solid-phase extraction sorbent is more suitable, exhibiting high precision (relative standard deviation 3.2%, n = 4) and a low limit of detection (60.0 ± 1.9 nmol·L(-1) ) for the isolation of l-phenylalanine. Based on these results, the combination of the Pickering emulsion polymerization and ion-pair dummy template imprinting is effective for preparing selective solid-phase extraction sorbents for the separation of amino acids and organic acids from complex biological samples.


Assuntos
Impressão Molecular , Fenilalanina/urina , Extração em Fase Sólida , Adsorção , Emulsões/química , Humanos , Tamanho da Partícula , Polimerização , Propriedades de Superfície
8.
J Sep Sci ; 38(18): 3279-3287, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26153852

RESUMO

In this study, dummy imprinting technology was employed for the preparation of l-phenylalanine-imprinted microspheres. Ionic liquids were utilized as both a "dummy" template and functional monomer, and 4-vinylpyridine and ethylene glycol dimethacrylate were used as the assistant monomer and cross-linker, respectively, for preparing a surface-imprinted polymer on poly(divinylbenzene) microspheres. By the results obtained by theoretical investigation, the interaction between the template and monomer complex was improved as compared with that between the template and the traditional l-phenylalanine-imprinted polymer. The batch experiments indicated that the imprinting factor reached 2.5. Scatchard analysis demonstrated that the obtained "dummy" molecularly imprinted microspheres exhibited an affinity of 77.4 M·10-4 , significantly higher that of a traditional polymer directly prepared by l-phenylalanine, which is in agreement with theoretical results. Competitive adsorption experiments also showed that the molecularly imprinted polymer with the dummy template effectively isolated l-phenylalanine from l-histidine and l-tryptophan with separation factors of 5.68 and 2.68, respectively. All these results demonstrated that the polymerizable ionic liquid as the dummy template could enhance the affinity and selectivity of molecularly imprinted polymer, thereby promoting the development of imprinting technology for biomolecules.

9.
Anal Bioanal Chem ; 406(28): 7221-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25260404

RESUMO

Thermal preparation of lysozyme-imprinted microspheres was firstly investigated by using biocompatible ionic liquid (IL) as a thermal stabilizer. The imprinted microspheres made with IL could obtain the good recognition ability to template protein, whereas the imprinted polymer synthesized in the absence of it had a similar adsorption capacity to the non-imprinted one. Furthermore, the preparation conditions of imprinted polymers (MIPs) including the content of IL, temperature of polymerization, and types of functional monomers and crosslinkers were systematically analyzed via circular dichroism spectrum and activity assay. The results illustrated that using hydroxyethyl acrylate as the functional monomer, ethylene glycol dimethacrylate as the crosslinker, 5 % IL as the stabilizer, and 75 °C as the reaction temperature could retain the structure of template protein as much as possible. The obtained MIPs showed excellent recognition ability to the template protein with the separation factor and selectivity factor value of 4.30 and 2.21, respectively. Consequently, it is an effective way to accurately imprint and separate template protein by cooperatively using circular dichroism spectroscopy and activity assay during the preparation of protein MIPs. The method of utilizing IL to stabilizing protein at high temperature would offer a good opportunity for various technologies to improve the development of macromolecules imprinting.


Assuntos
Líquidos Iônicos , Microesferas , Impressão Molecular , Muramidase/química , Muramidase/metabolismo , Animais , Galinhas , Dicroísmo Circular , Polímeros , Extração em Fase Sólida , Temperatura
10.
iScience ; 27(2): 108974, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38327790

RESUMO

In 2016, the Yangtze River Protection Strategy was proposed and a series of measures were applied to restore the health and function of the Yangtze River ecosystem. However, the impact of these measures on the carbon (C) sink capacity of the Yangtze River estuary wetlands has not been exhaustively studied. In this work, the effects of these measures on the C sink capacity of Yangtze River estuary wetlands were examined through the long-term monitoring of C fluxes, soil respiration, plant growth and water quality. The C flux of the Yangtze River estuary wetlands has become increasingly negative after the implementation of these measures, mainly owing to reduction in soil CO2 emission. The decrease in the chemical fertilizer release and returning farmland to wetland had led to the improvement of water quality in the estuary area, which further reduced soil heterotrophic microbial activity, and ultimately decreasing soil CO2 emissions of estuary wetlands.

11.
Environ Sci Pollut Res Int ; 30(23): 63580-63591, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37055687

RESUMO

The inland and estuary wetlands that characterized by different natural environment perform distinctly in soil carbon (C) sink. It was deemed that estuary wetland has a higher organic C accumulation rate than inland wetland, due to its higher primary production and tidal organics input, thus having higher organic C sink capacity. While from CO2 budge in view, whether does the large organic input from tide restrict CO2 sequestration capacity of estuary wetland has not been discussed comparing with inland wetland. In this study, inland and estuary wetlands were selected to study the potential of CO2 sequestration capacity. It was found that inland wetland had most of soil organic carbon (SOC) derived from plant C, which brought remarkable organic C content and nourished higher microbial biomass, dehydrogenase, and ß_glucosidase than estuary wetland. The estuary wetland instead accumulated less SOC, a considerable proportion of which came from tidal waters, therefore supporting lower microbial biomass and enzyme activities than that in inland wetland. However, estuary wetland was evaluated having higher capability in SOC mineralization than inland wetland in consideration of soil respiration (SR) and SR quotient. It was concluded that tidal organic C accelerated the SOC mineralization in estuarine wetland, thus weakening the CO2 sequestration. These results implied the importance of pollution control for reservation CO2 sink function in estuarine wetland.


Assuntos
Dióxido de Carbono , Áreas Alagadas , Carbono/análise , Solo , Biomassa , China , Sequestro de Carbono
12.
Environ Int ; 172: 107762, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36689865

RESUMO

Estuarine wetlands with high organic carbon (OC) accumulation rates due to their high plant biomass and interception of tide-derived OC are generally considered as large CO2 sinks. However, our previous study found that tidal OC input seems to stimulate soil CO2 emissions, potentially weakening CO2 sequestration in estuarine wetlands. To further verify this phenomenon, we first established a structural equation model, which confirmed a positive correlation between tidal OC input and soil organic carbon (SOC) and soil respiration. We then performed trace analysis to determine the stability of SOC derived from different sources and its effect on soil CO2 emissions by analyzing the input and retention of OC derived from tides and plants in the Yangtze Estuary wetlands. From upstream to downstream, as tidal OC input decreased, the relative retention ratio of the tidal OC in wetland soil increased from 1.259 to 2.148, whereas the relative retention ratio of plant OC in the soil decreased from 61.5% to 14.8%. Our findings indicated that the degradability of tidal OC was higher upstream than that downstream, but both inhibited plant OC degradation, thus providing an important reason for the higher CO2 emissions upstream of wetlands (with higher tidal OC input). In addition, the primarily contributor to CO2 (δ13) emissions' transforming from plant SOC (81.35%) to tidal SOC (91.18%) was an increase in organic matter input from the tide in a microcosm system. Consequently, a higher CO2 output than CO2 input (plant OC) due to the ready degradation of tidal OC consequently weakens the CO2 sequestration capacity of the estuarine wetlands. This phenomenon is cause for concern regarding the CO2 sink function of estuarine wetlands intercepting large amounts of organic matter.


Assuntos
Carbono , Áreas Alagadas , Carbono/análise , Dióxido de Carbono , Solo/química , Biomassa , Plantas , Sequestro de Carbono , China
13.
Int J Biol Macromol ; 253(Pt 2): 126857, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37703973

RESUMO

The development of sustainable and well-performing food packaging materials takes on critical significance, whereas it is still challenging. To overcome the shortcomings of polyvinyl alcohol (PVA) as a degradable packaging material, in this work, hydrophobic quaternary ammonium salt (QAS) modified cellulose nanofibers (CNF) and tannic acid­iron ion coordination complexes (TA-Fe) were adopted for the preparation of functional PVA films. The modified CNF (CNF-QAS) not only improved the mechanical properties and water resistance of PVA, but also endowed it with antibacterial ability. In addition, the synergistic antibacterial capability with CNF-QAS was achieved using TA-Fe with photothermal therapy. As a result, the modulus, elongation at break, tensile strength, and water contact angle of the prepared PVA films were examined as 88 MPa, 200 %, 11.7 MPa, and 94.8°, respectively. Furthermore, with the assistance of CNF-QAS and TA-Fe, the films inhibited the growth of E. coli and S. aureus by 99.8 % and 99.7 %, respectively, and they exhibited high cell viability of 90.5 % for L929 fibroblasts. Based on the above encouraging properties, the functional PVA films could significantly extend the shelf life of oranges for over two weeks, proving the excellent application prospects in the food packaging field.


Assuntos
Complexos de Coordenação , Nanofibras , Álcool de Polivinil/química , Embalagem de Alimentos , Nanofibras/química , Escherichia coli , Staphylococcus aureus , Celulose/farmacologia , Celulose/química , Compostos de Amônio Quaternário/farmacologia , Antibacterianos/farmacologia , Água
14.
Int J Biol Macromol ; 244: 125353, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37330076

RESUMO

With the trend of sustainable development and the complex medical environment, there is a strong demand for multimodal antibacterial cellulose wound dressing (MACD) with photothermal therapy (PTT). Herein, a novel MACD fabrication strategy with PTT was proposed and implemented through graft polymerization of an imidazolium ionic liquid monomer containing iron complex anion structure. The fabricated hydrogels exhibited excellent antibacterial properties because of the efficient photothermal conversion ability (68.67 %) of ionic liquids and the intrinsic structural characteristic of quaternary ammonium salts. The antibacterial ratio of cellulosic hydrogel dressings to S. aureus and E. coli could reach 99.57 % and 99.16 %, respectively. Additionally, the fabricated hydrogels demonstrated extremely low hemolysis rates (<5 %) and excellent cell viability (~>85 %). Furthermore, in vivo antibacterial experimental results proved that the fabricated antibacterial dressings could significantly accelerate wound healing. Therefore, the proposed strategy would provide a new method of designing and preparing high-performance cellulose wound dressings.


Assuntos
Celulose , Líquidos Iônicos , Celulose/farmacologia , Hidrogéis/farmacologia , Escherichia coli , Staphylococcus aureus , Polímeros , Antibacterianos/farmacologia , Cicatrização
15.
Carbohydr Polym ; 315: 121001, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37230624

RESUMO

With the increasing requirements for sustainable development and environmental protection, the design and development of bio-adsorbent based on the widely sourced cellulose have attracted widespread attention. In this study, a polymeric imidazolium satls (PIMS) functionalized cellulose foam (CF@PIMS) was conveniently fabricated. It was then employed to efficiently remove ciprofloxacin (CIP). Three imidazolium salts containing phenyl groups that can lead to multiple interactions with CIP were elaborately designed and then screened through a combination of molecular simulation and removal experiments to acquire the most significant binding ability of CF@PIMS. Besides, the CF@PIMS retained the well-defined 3D network structure as well as high porosity (90.3 %) and total intrusion volume (6.05 mL g-1) as the original cellulose foam (CF). Therefore, the adsorption capacity of CF@PIMS reached an astonishing value of 736.9 mg g-1, nearly 10 times that of the CF. Furthermore, the pH-affected and ionic strength-affected adsorption experiments confirmed that the non-electrostatic interaction took on a critical significance in the adsorption. The reusability experiments showed that the recovery efficiency of CF@PIMS was higher than 75 % after 10 adsorption cycles. Thus, a high-potential method was proposed in terms of the design and preparation of functionalized bio-adsorbent to remove waste matters from samples of the environment.


Assuntos
Ciprofloxacina , Poluentes Químicos da Água , Ciprofloxacina/química , Sais , Celulose/química , Adsorção , Poluentes Químicos da Água/química , Cinética
16.
Carbohydr Polym ; 294: 119835, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868779

RESUMO

The acquisition of efficient protein isolation substances is vital for proteomic research, whereas it's still challenging nowadays. Herein, an elaborately designed protein imprinted material based on a bacterial cellulose@ZIF-67 composite carrier (BC@ZIF-67) is proposed for the first time. In particular, due to the ultrafine fiber diameter and abundant hydroxyl functional groups of the bacterial cellulose, BC@ZIF-67 presented a compact arrangement structure similar to a pearl necklace, which greatly promoted template immobilization and mass transfer resistance in protein imprinting technology. Therefore, the protein-imprinted material (BC@ZIF-67@MIPs) fabricated by surface imprinting technology and template immobilization strategy could exhibit ultrahigh adsorption capacity (1017.0 mg g-1), excellent recognition (IF = 5.98) and rapid adsorption equilibrium time (50 min). In addition, based on the experiment outcomes, our team employed BC@ZIF-67@MIPs to enrich template protein in blended protein solutions and biosamples, identifying them as underlying candidates for isolating and purifying proteins.


Assuntos
Celulose , Impressão Molecular , Adsorção , Celulose/química , Proteínas/química , Proteômica
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(2): 280-3, 2011 Apr.
Artigo em Zh | MEDLINE | ID: mdl-21604485

RESUMO

C-arm based surgical navigation system is a kind of computer assisted surgery (CAS) system. In this paper, key techniques concerning this kind of system are presented. The key techniques mainly include XRII image distortion correction and C-arm imaging system calibration. On this basis, we designed relevant tools and made them fabricated, and developed a software system. Experimental results of human fresh spine sample showed that with the surgical navigation system, screw insertion accuracy was much higher than that without the surgical navigation system.


Assuntos
Algoritmos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodos , Calibragem , Humanos
18.
Carbohydr Polym ; 265: 118082, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33966846

RESUMO

Surfaces engineered to identify and enrich glycoproteins are of considerable interest in the diagnostic and detection fields. A boronate affinity (BA) material was proposed as a potential candidate for the isolation of glycoproteins. However, this material has the disadvantages of low efficiency and non-degradability. Herein, a novel dendrimer-amplified BA cellulose foam (PEI-PBA-CF) was fabricated via a mild two-step approach. The as-prepared PEI-PBA-CF exhibited a rapid adsorption equilibrium rate (within 60 min) and outstanding adsorption capacity for horseradish peroxidase (537.4 mg g-1) and ovalbumin (495.5 mg g-1). Furthermore, competitive adsorption experiments demonstrated that PEI-PBA-CF could achieve selective separation and purification of glycoproteins from complex biological samples due to the synergistic effect of the improved BA capacity by the dendrimer and the well-interconnected porous structure of the biomass matrix. Consequently, these cellulose foams might present new application opportunities in analytical and biomedical fields.


Assuntos
Ácidos Borônicos/química , Celulose/química , Dendrímeros/química , Glicoproteínas/isolamento & purificação , Adsorção , Clara de Ovo/química , Glicoproteínas/química , Peroxidase do Rábano Silvestre/química , Humanos , Ovalbumina/química , Polietilenoimina/química , Porosidade , Bases de Schiff/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
19.
ACS Appl Mater Interfaces ; 13(45): 54428-54438, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34734527

RESUMO

The use of a macromolecularly functional monomer and crosslinker (MFM) to stabilize and imprint a template protein is a new method to construct high-recognition protein-imprinted materials. In this study, for the first time, a "specially designed" block MFM with both "functional capability" and "crosslinking capability" segments was synthesized via reversible addition-fragmentation chain-transfer polymerization and used to fabricate bovine serum albumin (BSA)-imprinted microspheres (SiO2@MPS@MIPs-MFM) by the surface imprinting strategy. Results from circular dichroic spectrum experiments reflected that the block MFM could maintain the natural form of BSA, whereas its corresponding and equivalent micromolecularly functional monomer (MIM) seriously destroyed the secondary structure of proteins. Batch rebinding experiments showed that the maximum adsorption capacity and imprinting factor of SiO2@MPS@MIPs-MFM reached 314.9 mg g-1 and 4.02, which were significantly superior to that of MIM-based imprinted materials. In addition, since the crosslinking capability segments in block MFM involved zwitterionic functional groups with a protein-repelling effect, SiO2@MPS@MIPs-MFM showed better specific rebinding ability than the imprinted material prepared by MFM without this component. Besides, scanning electron microscopy and transmission electron microscopy images showed that the shell thickness of SiO2@MPS@MIPs-MFM was approximately 15 nm, and such a thin imprinted layer ensured its rapid adsorption equilibrium (120 min). As a result, SiO2@MPS@MIPs-MFM revealed fantastic selectivity and recognition ability in a mixed protein solution and could efficiently extract BSA from biological samples of bovine calf serum. The proposal of block MFM enriched the options and designability of monomers in protein imprinting technology, thereby laying a foundation for developing high-performance protein-imprinted materials.


Assuntos
Reagentes de Ligações Cruzadas/química , Metacrilatos/química , Impressão Molecular , Soroalbumina Bovina/química , Silanos/química , Dióxido de Silício/química , Animais , Bovinos , Reagentes de Ligações Cruzadas/síntese química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Microesferas , Estrutura Molecular , Propriedades de Superfície
20.
ACS Appl Mater Interfaces ; 13(26): 31010-31020, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160200

RESUMO

The development of high-performance protein-imprinted materials is vital to meet the requirements of proteomics research but remains a challenge. Herein, a new type of raspberry-like cytochrome C-imprinted nanoparticle was first designed and fabricated via surface imprinting technology combined with a template immobilization strategy. In particular, the state-of-the-art metal-organic framework (MOF)/carbon nanoparticle (CN) composites were selected as protein immobilization carriers for two advantages: (1) the composites reflected the intrinsic characteristics of MOFs including flexible design, facile preparation, and extensive interactions with proteins and (2) the utilization of composites also overcame the issue associated with the severe agglomeration of individual MOFs during the post-use process. Therefore, the as-prepared composites exhibited a regular raspberry-like shape with good dispersion (polydispersity index (PDI) < 0.25), high specific surface area (551.4 m2 g-1), and outstanding cytochrome C immobilization capacity (900 mg g-1). Furthermore, a zwitterionic monomer was chosen to participate in the synthesis of an imprinting layer to reduce the nonspecific binding with proteins. As a result, the unique design presented here in both the protein immobilization carrier and the selected polymer composition endowed the imprinted material (noted as CN@UIO-66@MIPs) with the excellent ability for cytochrome C enrichment with extremely high recognition ability (imprinting factor (IF) = 6.1), rapid adsorption equilibrium time (40 min), and large adsorption capacity (815 mg g-1). Furthermore, encouraged by the experimental results, we successfully used CN@UIO-66@MIPs to specifically capture cytochrome C in mixed protein solutions and biological samples, which proved them to be a potential candidate for protein separation and purification.


Assuntos
Citocromos c/isolamento & purificação , Estruturas Metalorgânicas/química , Polímeros Molecularmente Impressos/química , Nanopartículas/química , Adsorção , Animais , Carbono/química , Fracionamento Químico/métodos , Citocromos c/química , Cinética , Compostos Organometálicos/química , Ácidos Ftálicos/química , Ratos
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