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1.
Water Res ; 250: 121078, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38159540

RESUMO

Disinfection is vital in ensuring water safety. However, the traditional chlorine disinfection process is prone to producing toxic and harmful disinfection by-products (DBPs). The combination of quaternary ammonium polymer and the chlorine disinfection process can solve this shortcoming. Currently, research on the control of DBPs through the combined process is not systematic and the control effect between reducing the dosage of disinfectants and DBPs remains to be studied. Quaternized cyclodextrin polymers have attracted increasing attention due to their excellent adsorption and antibacterial properties, but their synergistic effect with chlorine disinfection is still unclear. In this study, a magnetic quaternized cyclodextrin polymer (MQCDP) is synthesized in an ionic liquid green system, and a combined process of MQCDP treatment and chlorine disinfection is established. The disinfection performance of the combined process on the actual water body along with its reducing effect on the amount of chlorine disinfectant as well as the trihalomethanes (THMs) and haloacetic acids (HAAs) DBPs are explored. MQCDP has a porous structure with a specific surface area of 825 m2 g-1 and is easily magnetically separated. MQCDP can remove most of the natural organic matter (UV254 absorbance decreased by 97 %) in the water at the dosage of 1 g L-1 and kill bacteria with a sterilization rate of 85 %. Compared with disinfection using chlorine alone, the combined process has higher disinfection efficiency and significantly reduces the amount of disinfectant used. A concentration of 5 mg/L of NaClO was needed to meet the standard by chlorine disinfectant alone, while only 2 mg/L of NaClO can meet the standard for the combined process, indicating 60 % of the chlorine demand was reduced. More importantly, the combined process can significantly reduce the generation potential of DBPs. When 10 mg/L of NaClO is added, the THMs and HAAs generated by the combined process decreased by 65 % and 34 %, respectively, compared with the levels produced by single chlorine disinfection. The combined process can reduce the dosage of chlorine disinfectant and MQCDP can adsorb humic acid DBP precursors in raw water, thus lowering the generation of DBPs during disinfection. In summary, MQCDP has excellent separation and antibacterial ability, and its synergistic effects combined with the chlorine disinfection process are of great significance for controlling the amount of disinfectant and the formation potential of DBPs, which has potential applications in actual water treatment.


Assuntos
Celulose , Ciclodextrinas , Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Desinfecção , Cloro/química , Desinfetantes/química , Cloretos/química , Halogenação , Trialometanos/química , Antibacterianos/farmacologia , Fenômenos Magnéticos , Poluentes Químicos da Água/análise
2.
Environ Res ; 212(Pt D): 113391, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35597293

RESUMO

Taihu Lake is the most important drinking water source of the major cities in the Yangtze River Delta. The pollution of endocrine disruptors (EDCs)in Taihu Lake has been increasing recently, the accurate determination is an important guide for predicting its health risks and developing appropriate controls. Monitoring organic pollutants in water using the diffusive gradient in thin film technique (DGT) has attracted much attention due to more accuracy and convenience than the grab sampling methods. In this study, a novel cyclodextrin polymer (CDP) synthesized by the simple and green method in water was taken as an adsorbent for the binding gel. Four endocrine-disrupting chemicals (EDCs), bisphenol A (BPA), 17α-ethinylestradiol (EE2), 17ß-estradiol (E2), and estriol (E3), were taken as models to determine the diffusion coefficients (4.68 × 10-6, 3.38 × 10-6, 3.34 × 10-6 and 4.31 × 10-6 cm2/s) and to test the performance of DGT, such as adsorption capacity and deployment time (1-5 day). The assembled CDP-DGT was adopted to determine four EDCs in a simulated water environment (3-9 of pH, 0.001-0.5 M of ionic strength (IS), and dissolved organic matter (DOM) of 0-20 mg/L). The ability of CDP-DGT sampling was verified in the Jiuxiang River and was carried out for a large-scale field application of in situ sampling EDCs in Taihu Lake basin. The results show that the total EDCs concentration range and the estradiol equivalent concentrations (EEQ) in Taihu Lake and its main rivers are 2.78 ng/L to 11.08 ng/L and 2.62 ng/L to 10.91 ng/L, respectively. The risk quotients (RQs) of all sampling sites in the region were greater than 1, indicating that EDCs pose a serious threat to aquatic organisms in the area. Therefore, the monitoring of EDCs in the Taihu Lake basin should be further strengthened.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Celulose , China , Ciclodextrinas , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Estradiol , Géis , Lagos/química , Medição de Risco , Rios/química , Água , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 808: 151892, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34826470

RESUMO

Poyang Lake is the first freshwater lake in China, which is an important drinking water source. In recent years, industrial pollution has led to the increased phthalate acid esters (PAEs) in Poyang Lake. PAEs are a class of typical endocrine disruptors that can accumulate in organisms and interfere with their secretion systems. Thus, the accurate determination of PAEs in Poyang Lake is important for health risk prediction and the development of corresponding control means. Monitoring organic pollutants in water using the diffusive gradient in thin films technique (DGT) has attracted much attention due to more accuracy and convenience than the traditional methods. This study used an inexpensive amphiphilic cyclodextrin polymer (PBCD) as the sorbent for the binding gel. This new binding gel has an ultra-high specific surface area and excellent adsorption performance. Diffusion coefficients of the five PAEs were determined, and the performance of DGT such as adsorption capacity and deployment time (1-4 days) was tested using five PAEs as models. The assembled PBCD-DGT was used to examine the performance in a complex simulated water environment. The sampling capability of PBCD-DGT was verified in Yangshan Lake, and a large-scale field application was conducted in Poyang Lake basin. The results of 11 sampling points showed that the concentration ranges of dimethyl phthalate, diethyl phthalate, diallyl phthalate, dipropyl phthalate, and dibutyl phthalate were 434-2594 ng/L, 40-314 ng/L, 80-527 ng/L, 45-308 ng/L, and ND-182 ng/L, respectively. The health risk index (HI) and ecological risk quotient (RQ) values of PAEs in the Poyang Lake watershed were far below 1, indictating a lower health and ecological risk. Considering that PAEs are bioaccumulative and persistent, it is very necessary to continue to pay attention to its pollution status and health and ecological risk changes in Poyang Lake Basin in the future.


Assuntos
Água Potável , Ácidos Ftálicos , Poluentes Químicos da Água , Celulose , China , Ciclodextrinas , Dibutilftalato/análise , Monitoramento Ambiental , Ésteres/análise , Lagos , Ácidos Ftálicos/análise , Medição de Risco , Tecnologia , Poluentes Químicos da Água/análise
4.
ACS Nano ; 15(12): 19244-19255, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34843205

RESUMO

Nanoparticles are a promising solution for delivery of a wide range of medicines and vaccines. Optimizing their design depends on being able to resolve, understand, and predict biophysical and therapeutic properties, as a function of design parameters. While existing tools have made great progress, gaps in understanding remain because of the inability to make detailed measurements of multiple correlated properties. Typically, an average measurement is made across a heterogeneous population, obscuring potentially important information. In this work, we develop and apply a method for characterizing nanoparticles with single-particle resolution. We use convex lens-induced confinement (CLiC) microscopy to isolate and quantify the diffusive trajectories and fluorescent intensities of individual nanoparticles trapped in microwells for long times. First, we benchmark detailed measurements of fluorescent polystyrene nanoparticles against prior data to validate our approach. Second, we apply our method to investigate the size and loading properties of lipid nanoparticle (LNP) vehicles containing silencing RNA (siRNA), as a function of lipid formulation, solution pH, and drug-loading. By taking a comprehensive look at the correlation between the intensity and size measurements, we gain insights into LNP structure and how the siRNA is distributed in the LNP. Beyond introducing an analytic for size and loading, this work allows for future studies of dynamics with single-particle resolution, such as LNP fusion and drug-release kinetics. The prime contribution of this work is to better understand the connections between microscopic and macroscopic properties of drug-delivery vehicles, enabling and accelerating their discovery and development.


Assuntos
Portadores de Fármacos , Nanopartículas , Lipossomos , Tamanho da Partícula , RNA Interferente Pequeno
5.
Anal Bioanal Chem ; 412(30): 8379-8389, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33000307

RESUMO

Bacteria are everywhere and pose severe threats to human health and safety. The rapid classification and sensitive detection of bacteria are vital steps of bacterial community research and the treatment of infection. Herein, we developed optical property-superior and heavy metal-free ZnCuInSe quantum dots (QDs) for achieving rapid discrimination of Gram-positive/Gram-negative bacteria by the naked eye; driven by the structural differences of bacteria, ZnCuInSe QDs are effective in binding to Gram-positive bacteria, especially Staphylococcus aureus (S. aureus), in comparison with Gram-negative bacteria and give discernable color viewed by the naked eye. Meanwhile, based on its distinctive fluorescence response, the accurate quantification of S. aureus was investigated with a photoluminescence system in the concentration ranges of 1 × 103 to 1 × 1011 CFU/mL, with a limit of detection of 1 × 103 CFU/mL. Furthermore, we demonstrated the feasibility of ZnCuInSe QDs as a fluorescence probe for imaging S. aureus. This simple strategy based on ZnCuInSe QDs provides an unprecedented step for rapid and effective bacterial discrimination, detection, and imaging.


Assuntos
Cobre/química , Índio/química , Pontos Quânticos/química , Selênio/química , Staphylococcus aureus/classificação , Zinco/química , Limite de Detecção , Testes de Sensibilidade Microbiana , Solubilidade , Staphylococcus aureus/isolamento & purificação , Água/química
6.
Nanotechnology ; 31(39): 395602, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32340006

RESUMO

A novel visible light-driven photocatalyst (represented as Mn-CdS/ZCISe/CIS/TiO2) for the passivation of E. coli was prepared with TiO2 nanowires as support and using CuInS2 (CIS) and ZnCuInSe (ZCISe) quantum dots (QDs), as well as Mn-doped CdS (Mn-CdS) nanoparticles (NPs) as sensitizers. The use of CIS and ZCISe QDs and Mn-CdS NPs extends the light harvest region to visible light. The photoelectric conversion efficiency was consequently improved, with a photocurrent density of 12.5 mA cm-2, about 60 times that of pure TiO2 nanowires. The germicidal efficiency of the photocatalyst was assessed by passivation of E. coli, 96% bacteria in 50 ml 105 colony forming units (CFU) ml-1 solution were killed within 50 min. Besides the high efficiency, the composite has good stability and satisfactory recycling performance. The antibiotic mechanism was also performed by using photoluminescence and a scavenging agent of different active matter, revealing that the photo-generated holes play a major role in the sterilization process.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Fotoquimioterapia/métodos , Titânio/farmacologia , Antibacterianos/química , Compostos de Cádmio/química , Catálise , Cobre/química , Escherichia coli/crescimento & desenvolvimento , Índio/química , Manganês/química , Viabilidade Microbiana/efeitos dos fármacos , Nanofios , Pontos Quânticos , Selênio/química , Sulfetos/química , Titânio/química
7.
ACS Appl Mater Interfaces ; 12(10): 12165-12175, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32057224

RESUMO

Natural organic matter (NOM), organic micropollutants (OMPs), and detrimental microorganisms are three major pollutants that affect water quality. To remove these pollutants, a quaternary ammonium-functionalized ß-cyclodextrin polymer (ß-CDP) is successfully synthesized in the aqueous phase. The N2 and CO2 adsorption/desorption analysis showed that the polymer mainly contains ultra-micropores (<1 nm), with a Langmuir surface area of 89 m2 g-1. Two kinds of NOM, humic acid and fulvic acid, and five OMPs, 2-naphthol (2-NO), 3-phenylphenol (3-PH), 2,4,6-trichlorophenol (2,4,6-TCP), bisphenol A (BPA), and bisphenol S (BPS), were selected as model pollutants to study the performance of ß-CDP and three kinds of commercial adsorbents, including granular activated carbon, DARCO-AC, and two resins, XAD-4 and D-201, were used for comparison. The polymer shows ultrarapid adsorption kinetics for the removal of these pollutants, with pseudo-second-order rate constants two to three orders of magnitude higher than that of the commercial activated carbon and resins. Due to the different adsorption sites of NOM and OMPs, ß-CDP can simultaneously remove these pollutants without competitive adsorption. The maximum adsorption capacity of ß-CDP for HA, FA, 2-NO, 3-PH, 2,4,6-TCP, BPA, and BPS based on the Langmuir model is 40, 166, 74, 101, 108, 103, and 117 mg g-1, respectively. After use, the polymer can be easily regenerated at room temperature. In addition, ß-CDP also showed excellent bactericidal properties due to the quaternary ammonium groups. At a concentration of 15 g L-1, ß-CDP can remove 98% of the tested Escherichia coli. Moreover, the synthesis of ß-CDP is simple, green, and easy to industrialize. All of these findings indicate that ß-CDP, as an ideal multifunctional material, presents potential for practical applications for water treatment and disinfection.


Assuntos
Celulose/química , Ciclodextrinas/química , Poluentes Químicos da Água , Purificação da Água/métodos , beta-Ciclodextrinas/química , Adsorção , Benzopiranos/química , Química Verde/métodos , Substâncias Húmicas/análise , Fenóis/química , Fenóis/isolamento & purificação , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
8.
Environ Res ; 180: 108796, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629085

RESUMO

Adsorption is one of the most preferred techniques in the advanced treatment of dyeing wastewater. Magnetic porous materials with good adsorption performance, excellent reusability, and a green synthesis route are highly desirable adsorbents in commerce. In this study, we synthesized a magnetic ß-cyclodextrin polymer (MNP-CM-CDP) containing many macro- and ultramicropores in aqueous phase. CO2 adsorption-desorption isotherms and a dye adsorption method provided Langmuir specific surface areas for the MNP-CM-CDP of 114.4 m2 g-1 and 153 m2 g-1, respectively. Model pollutants (BPA, MB, BO2, RhB, Cr(III), Pb(II), Zn(II), and Cu(II)) were rapidly and efficiently removed from the aqueous solution by the MNP-CM-CDP. In addition, the polymer could be easily separated from the solution under an external magnetic field. The adsorption of the contaminants was dependent on pH, while the effects of ionic strength and humic acid were slight in the concentration range studied. The polymer could be easily regenerated at room temperature and retained good adsorption performance. Moreover, the MNP-CM-CDP showed good feasibility for the removal of pollutants from actual dyeing wastewater samples.


Assuntos
Poluentes Ambientais , Metais Pesados , Águas Residuárias , Poluentes Químicos da Água , Adsorção , Celulose , Ciclodextrinas , Fenômenos Magnéticos , Polímeros
9.
Mikrochim Acta ; 186(11): 691, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31605264

RESUMO

Cobalt-doped nanoporous carbon (Co-NPC) with dodecahedral shape was pyrolytically synthesized and applied as a sorbent and matrix for the enrichment and analysis of small molecules by surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). Extremely low detection limits were accomplished for cetyltrimethylammonium bromide (1 fg·mL-1), and Rhodamine B (1 fg·mL-1) in water, and Malachite Green and its metabolite in fish blood and fish extracts (pg·mL-1 concentrations). Graphical abstract Schematic representation of cobalt-doped nanoporous carbons (Co-NPCs) applied as SALDI matrix for analysis of toxic contaminants in fish and receipt papers. The Co-NPCs have a high desorption/ionization efficiency and low limit of detection.

10.
Chem Commun (Camb) ; 54(49): 6260-6263, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29745392

RESUMO

It is a challenge to develop microemulsions which can serve as nanoreactors for the synthesis of nanoparticles and chemical reactions at high temperature. In this work, a class of novel high temperature microemulsions consisting solely of ionic liquids have been designed and prepared for the first time. It is found that nanoscale droplets formed in the ionic liquid microemulsions can be maintained up to 200 °C, and the size distribution of the droplets can be easily tuned by selection of the ionic liquids and varying compositions of the systems. By using such microemulsions as nanoreactors, porous metals such as Pt have been prepared at 180 °C without using any purposely added reductant.

11.
Chem Biol Drug Des ; 87(4): 635-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26613384

RESUMO

A class of novel quinazoline derivatives bearing various C-4 aniline moieties was synthesized and biologically evaluated as potent epidermal growth factor receptor (EGFR) inhibitors for intervention of non-small-cell lung cancer (NSCLC). Most of these inhibitors are comparable to gefitinib in inhibiting these cancer cell lines, and several of them even displayed superior inhibitory activity. In particular, analogue 5b with an IC50 of 0.10 µm against the EGFR wild-type A431 cells and 5c with an IC50 of 0.001 µm against the gefitinib-sensitive HCC827 cells (EGFR del E746-A750) was identified as highly active EGFR inhibitors. It was also significant that the discovered analogue 2f, not only has high potency against the gefitinib-sensitive cells (IC50 = 0.031 µm), but also possesses remarkably improved activity against the gefitinib-resistant cells. In addition, the enzymatic assays and the Western blot analysis for evaluating the effects of the typical inhibitors indicated that these molecules strongly interfere with the EGFR target.


Assuntos
Compostos de Anilina/química , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/patologia , Quinazolinas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Quinazolinas/química , Espectrometria de Massas por Ionização por Electrospray
12.
Curr Pharm Des ; 21(7): 950-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25269561

RESUMO

Searching for safe and effective treatments for HIV infection is still a great challenge worldwide in spite of the 27 marketed anti-HIV drugs and the powerful highly active antiretroviral therapy (HAART). As a promising prospect for generation of new HIV therapy drugs, multiple ligands (MDLs) were greatly focused on recently due to their lower toxicity, simplified dosing and patient adherence than single-target drugs. Till now, by disrupting two active sites or steps of HIV replications, a number of HIV dual inhibitors, such as CD4-gssucap120 inhibitors, CXCR4-gp20 inhibitors, RT-CXCR4 inhibitors, RT-protease inhibitors, RT-integrase inhibitors, and RTassociated functions inhibitors have been identified. Generally, these dual inhibitors were discovered mainly through screening approaches and design strategies. Of these compounds, the molecules bearing small skeletons exhibited strong anti-HIV activity and aroused great attention recently. Reviewing the progress of the dual small-molecule HIV inhibitors from the point of view of their scaffolds and discovery strategies will provide valuable information for producing more effective anti-HIV drugs. In this regard, novel dual small-molecule HIV inhibitors were illustrated, and their discovery paradigms as the major contents were also summarized in this manuscript.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/química , Descoberta de Drogas/tendências , HIV-1/efeitos dos fármacos , Animais , Fármacos Anti-HIV/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/metabolismo , Humanos , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo
13.
Chem Commun (Camb) ; 48(64): 7946-8, 2012 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-22760593

RESUMO

Metal-organic polyhedra (MOP) nanocages were successfully surface functionalized via ionic self-assembly and the ordered honeycomb architecture of the encapsulated MOP nanocages was also fabricated at the air/water surface. The results provide a novel synthetic method and membrane processing technique of amphiphilic MOP nanocages for various applications.


Assuntos
Nanoestruturas/química , Compostos Organometálicos/síntese química , Ar , Íons/química , Modelos Moleculares , Compostos Organometálicos/química , Tamanho da Partícula , Propriedades de Superfície , Água/química
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