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1.
J Sep Sci ; 43(18): 3683-3690, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32700400

RESUMO

Molecularly imprinted polymers were prepared via ß-cyclodextrin-stabilized oil-in-water Pickering emulsion polymerization for selective recognition and adsorption of erythromycin. The synthesized molecularly imprinted polymers were spherical in shape, with diameters ranging from 20 to 40 µm. The molecularly imprinted polymers showed high adsorption capacity (87.08 mg/g) and adsorption isotherm data fitted well with Langmuir model. Adsorption kinetics study demonstrated that the molecularly imprinted polymers acted in a fast adsorption kinetic pattern and the adsorption features of molecularly imprinted polymers followed a pseudo-first-order model. Adsorption selectivity analysis revealed that molecularly imprinted polymers had a much better specificity for erythromycin than that for spiramycin or amoxicillin, and the relative selectivity coefficient values on the bases of spiramycin and amoxicillin were 3.97 and 3.86, respectively. The Molecularly imprinted polymers also showed a satisfactory reusability after four times of regeneration. In addition, molecularly imprinted polymers exhibited good adsorption capacities for erythromycin under complicated environment, that is, river water and milk. These results proved that the as-prepared molecularly imprinted polymers is a potent absorbent for selective recognition of erythromycin, and therefore it may be a promising candidate for practical applications, such as wastewater treatment and detection of erythromycin residues in food.


Assuntos
Eritromicina/análise , Leite/química , Polímeros Molecularmente Impressos/química , Rios/química , beta-Ciclodextrinas/química , Animais , Emulsões , Polímeros Molecularmente Impressos/síntese química , Polimerização , Água/química
2.
Environ Sci Pollut Res Int ; 31(11): 16241-16255, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340302

RESUMO

The consumption of disposable plastic products and disinfectants has surged during the global COVID-19 pandemic, as they play a vital role in effectively preventing and controlling the spread of the virus. However, microplastic pollution and the excessive or improper use of disinfectants contribute to the increased environmental tolerance of microorganisms. Microplastics play a crucial role as vectors for microorganisms and plankton, facilitating energy transfer and horizontal gene exchange. The increase in the use of disinfectants has become a driving force for the growth of disinfectant resistant bacteria (DRB). A large number of microorganisms can have intense gene exchange, such as plasmid loss and capture, phage transduction, and cell fusion. The reproduction and diffusion rate of DRB in the environment is significantly higher than that of ordinary microorganisms, which will greatly increase the environmental tolerance of DRB. Unfortunately, there is still a huge knowledge gap in the interaction between microplastics and disinfectant resistance genes (DRGs). Accordingly, it is critical to comprehensively summarize the formation and transmission routes of DRGs on microplastics to address the problem. This paper systematically analyzed the process and mechanisms of DRGs formed by microbes. The interaction between microplastics and DRGs and the contribution of microplastic on the diffusion and spread of DRGs were expounded. The potential threats to the ecological environment and human health were also discussed. Additionally, some challenges and future priorities were also proposed with a view to providing useful basis for further research.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos , Pandemias , Monitoramento Ambiental , Poluição Ambiental/análise , Meio Ambiente , Bactérias/genética , Ecossistema , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 916: 170299, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272086

RESUMO

The detrimental effects of plastic and microplastic accumulation on ecosystems are widely recognized and indisputable. The emergence of biodegradable plastics (BPs) offers a practical solution to plastic pollution. Problematically, however, not all BPs can be fully degraded in the environment. On the contrary, the scientific community has demonstrated that BPs are more likely than conventional plastics (CPs) to degrade into micro/nanoplastics and release additives, which can have similar or even worse effects than microplastics. However, there is very limited information available on the environmental toxicity assessment of BMPs. The absence of a toxicity evaluation system and the uncertainty regarding combined toxicity with other pollutants also impede the environmental toxicity assessment of BMPs. Currently, research is focused on thoroughly exploring the toxic effects of biodegradable microplastics (BMPs). This paper reviews the pollution status of BMPs in the environment, the degradation behavior of BPs and the influencing factors. This paper comprehensively summarizes the ecotoxicological effects of BPs on ecosystems, considering animals, plants, and microorganisms in various environments such as water bodies, soil, and sediment. The focus is on distinguishing between BMPs and conventional microplastics (CMPs). In addition, the combined toxic effects of BMPs and other pollutants are also being investigated. The findings suggest that BMPs may have different or more severe impacts on ecosystems. The rougher and more intricate surface of BMPs increases the likelihood of causing mechanical damage to organisms and breaking down into smaller plastic particles, releasing additives that lead to a series of cascading negative effects on related organisms and ecosystems. In the case of knowledge gaps, future research is also proposed and anticipated to investigate the toxic effects of BMPs and their evaluation.


Assuntos
Plásticos Biodegradáveis , Poluentes Ambientais , Animais , Plásticos Biodegradáveis/toxicidade , Ecossistema , Poluentes Ambientais/toxicidade , Poluição Ambiental , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade
4.
Food Chem ; 449: 139291, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608609

RESUMO

The residues of erythromycin (ERY) may have negative impacts on the ecological environment, health, and food safety. How to detect ERY effectively and visually is a challenging issue. Herein, we synthesized a molecularly imprinted polymer based nanozymes for selective detection of erythromycin (ERY-MIPNs) at neutral pH, and developed a mobile phone-assisted bicolor colorimetric detection system. This system produced a wide range of color changes from blue to pinkish purple as the ERY concentration increased, making it easy to capture the visualization result. Also, the system showed good sensitivity to ERY ranging from 15 to 135 µM, with a detection limit of 1.78 µM. In addition, the system worked well in the detection of ERY in river water and milk, with the recoveries of 95.57% âˆ¼ 103.20%. These data suggests that this strategy is of considerable potential for practical applications and it provides a new idea for visual detection with portable measurement.


Assuntos
Colorimetria , Eritromicina , Leite , Rios , Poluentes Químicos da Água , Leite/química , Colorimetria/métodos , Animais , Rios/química , Eritromicina/análise , Eritromicina/isolamento & purificação , Poluentes Químicos da Água/análise , Telefone Celular , Impressão Molecular , Contaminação de Alimentos/análise , Limite de Detecção , Antibacterianos/análise , Polímeros Molecularmente Impressos/química
5.
Sci Total Environ ; 912: 169571, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38142997

RESUMO

The application of organic fertilizers is becoming an undeniable source of microplastics and antibiotic resistance genes (ARGs) in agricultural soils. The complex microbial activity further transfers resistance genes and their host bacteria to agricultural products and throughout the entire food chain. Therefore, the current main focus is on reducing the abundance of microplastics and ARGs in organic fertilizers at the source, as well as managing microplastics and ARGs in soil. The control of microplastic abundance in organic fertilizers is currently only achieved through pre-composting selection and other methods. However, there are still many shortcomings in the research on the distribution characteristics, propagation and diffusion mechanisms, and control technologies of ARGs, and some key scientific issues still need to be urgently addressed. The high-temperature composting of organic waste can effectively reduce the abundance of ARGs in organic fertilizers to a certain extent. However, it is also important to consider the spread of ARGs in residual antibiotic-resistant bacteria (ARB). This article systematically explores the pathways and interactions of microplastics and resistance genes entering agricultural soils through the application of organic fertilizers. The removal of microplastics and ARGs from organic fertilizers was discussed in detail. Based on the limitations of existing research, further investigation in this area is expected to provide valuable insights for the development and practical implementation of technologies aimed at reducing soil microplastics and resistance genes.


Assuntos
Microplásticos , Plásticos , Fertilizantes/análise , Genes Bacterianos , Antagonistas de Receptores de Angiotensina , Microbiologia do Solo , Esterco/microbiologia , Inibidores da Enzima Conversora de Angiotensina , Solo , Bactérias/genética , Antibacterianos
6.
Chemosphere ; 355: 141680, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479683

RESUMO

In this study, a novel Fe3O4-based biochar coupled surface-imprinted polymer was constructed via simple hydrothermal route for salicylic acid recognition and degradation in advanced oxidation processes. The material exhibited excellent adsorption capability, up to 118.23 mg g-1, and efficient degradation performance, 87.44% removal rate within 240 min, based on integrating the advantages of both huge specific surface area as well as abundant functional groups from biochars and specific recognition sites from imprinted cavities. Moreover, high selectivity coefficient (11.67) showed stable recognition in single and binary systems. SO4•- and •OH were confirmed as reactive oxygen species in catalytic reaction according to quenching experiments and EPR analysis. The degradation mechanism and pathway were unraveled by DFT calculations and LC-MS. Furthermore, the results of toxicity evaluation, stability and reusability demonstrated application potential in the field of water environment restoration. This study confirmed that molecular imprinting provided a promising solution to targeted removal of emerging environmental pollutants by degrading after the enrichment of pollutants to the composites surface.


Assuntos
Carvão Vegetal , Impressão Molecular , Águas Residuárias , Polímeros Molecularmente Impressos , Ácido Salicílico , Polímeros , Impressão Molecular/métodos , Adsorção
7.
Sci Total Environ ; 905: 167192, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730038

RESUMO

Microplastic pollution in the environment has aroused widespread concerns, however, the potential environmental risks caused by excessive use of disinfectants are still unknown. Disinfectants with doses below the threshold can enhance the communication of resistance genes in pathogenic microorganisms, promoting the development and spread of antimicrobial activity. Problematically, the intensification of microplastic pollution and the increase of disinfectant consumption will become a key driving force for the growth of disinfectant resistance bacteria (DRB) and disinfectant resistance genes (DRGs) in the environment. Disinfection plays a crucial role in ensuring water safety, however, the presence of microplastics and DRGs seriously disturb the water disinfection process. Microplastics can reduce the concentration of disinfectant in the local environment around microorganisms and improve their tolerance. Microorganisms can improve their resistance to disinfectants or generate resistance genes via phenotypic adaptation, gene mutations, and horizontal gene transfer. However, very limited information is available on the impact of DRB and DRGs on disinfection process. In this paper, the contribution of microplastics to the migration and transmission of DRGs was analyzed. The challenges posed by the presence of microplastics and DRGs on conventional disinfection were thoroughly discussed. The knowledge gaps faced by relevant current research and further research priorities have been proposed in order to provide a scientific basis in the future.


Assuntos
Desinfetantes , Desinfetantes/análise , Desinfecção , Microplásticos , Plásticos , Água , Bactérias/genética
8.
Chemosphere ; 340: 139924, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37625491

RESUMO

With the intensification of microplastic pollution globally, aquaculture environments also face risks of microplastic contamination through various pathways such as plastic fishing gear. Compared to wild aquatic products, cultured aquatic products are more susceptible to microplastic exposure through fishing tackle, thus assessing the impacts of microplastics on farmed species and human health. However, current research on microplastic pollution and its ecological effects in aquaculture environments still remains insufficient. This article comprehensively summarizes the pollution characteristics and interrelationships of microplastics in aquaculture environments. We analyzed the influence of microplastics on the sustainable development of the aquaculture industry. Then, the potential hazards of microplastics on pond ecosystems and consumer health were elucidated. The strategies for removing microplastics in aquaculture environments are also discussed. Finally, an outlook on the current challenge and the promising opportunities in this area was proposed. This review aims to evaluate the value of assessing microplastic pollution in aquaculture environments and provide guidance for the sustainable development of the aquaculture industry.


Assuntos
Microplásticos , Plásticos , Humanos , Ecossistema , Aquicultura , Contaminação de Medicamentos
9.
Colloids Surf B Biointerfaces ; 217: 112703, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35853394

RESUMO

Injectable hydrogels are potential local drug delivery systems since they contain plenty of water and soft like biological tissues. Such hydrogels could be injected directly into the tumor site where the drug is released under the tumor microenvironment. However, drug loaded hydrogels for cancer treatment based on lipoic acid (natural small molecule) have not been exploited. Here, a novel poly(lipoic acid)-poly(ethylene glycol) (PEG-PTA) hydrogels were prepared through a two-step reaction. The hydrogels contained disulfide bonds, so they could be degraded via the thiol exchange reaction with the abundant GSH in the tumor microenvironment, and subsequently release the drug. The results in vitro and at cellular level showed that the hydrogels were degraded and released the drugs only in the presence of GSH. Therefore, the injectable GSH-responsive hydrogels are promising to be served as an intelligent drug delivery system for cancer treatment.


Assuntos
Hidrogéis , Ácido Tióctico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Hidrogéis/química , Polietilenoglicóis/química , Ácido Tióctico/farmacologia
10.
Colloids Surf B Biointerfaces ; 208: 112126, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34600360

RESUMO

Selective cancer cell targeting, controlled drug release, easy construction and multiple therapeutic modalities are some of the desirable characteristics of drug delivery systems. We designed and built simple capsule-like molecular imprinted polymer (MIP)-based nanoparticles for targeted and chemo-photothermal synergistic cancer therapy. Using dopamine (DA) as functional monomer, cross-linking agent as well as photo-thermal agent, ZIF-8 (zeoliticimidazolate framework-8) as drug carrier, epitope of EGFR (epidermal growth factor receptor) as template molecules, molecular imprinted polymer (MIP) drug carrier was constructed. The ability of MIP layer to bind to EGFR epitope endowed the MD (DOX@MIP) particles to recognize EGFR-overexpressing cancer cells, while the pH-responsiveness and photothermal conversion ability of PDA (polydopamine) achieved chemo-photothermal synergistic effects upon NIR irradiation. Taken together, the MD nanoparticles integrated cancer cell targeting recognition, intelligent drug release, biocompatibility and chemo-photothermal effects, and is therefore a promising tool for targeted cancer therapy with minimal toxicity to normal cells, as well as tumor imaging.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Doxorrubicina , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Indóis , Neoplasias/tratamento farmacológico , Fototerapia , Polímeros
11.
Shanghai Kou Qiang Yi Xue ; 21(3): 350-3, 2012 Jun.
Artigo em Zh | MEDLINE | ID: mdl-22885503

RESUMO

PURPOSE: To evaluate the effect of combination of Nance and TPA on the use of MBT appliance to treat Class II division I malocclusion. METHODS: Nineteen cases of Class II division I malocclusion, aged from 12 to 16 years, underwent Nance arch and TPA in the use of MBT appliance to reinforce molar anchorage. Cephalometric analysis and model measurements were conducted and compared before and after treatment using SAS8.0 software package. RESULTS: The average forward movement of the first maxillary molar was (1.97 ± 0.696)mm, but still less than 1/3 of the extraction space.U1-SN reduced 10.97° ± 3.81°.There was no significant difference in GoGn-Sn angle,ALFH /AFH and posterior dental arch width(P>0.05).The soft tissue profile (Ls-E,Ls-Snpg,Cm-Sn-Ls) was improved remarkably (P<0.01). CONCLUSION: The combination of Nance and TPA might be effective and simple anchorage in three dimensions.


Assuntos
Má Oclusão Classe II de Angle , Fios Ortodônticos , Adolescente , Cefalometria , Assistência Odontológica , Humanos , Má Oclusão , Dente Molar
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