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1.
Environ Res ; 252(Pt 2): 118893, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604485

RESUMO

Pesticides can have harmful impacts on the environment and living organisms. Thus, removing them from polluted water is crucial. In this study, a bionanocomposite of carboxymethyl tragacanth-grafted-poly(3-aminophenol)/zinc oxide@iron oxide (CMT-g-P3AP/ZnO@Fe3O4) synthesized by in situ copolymerization as an efficient adsorbent to eliminate the acetamiprid pesticide from polluted water. The CMT-g-P3AP/ZnO@Fe3O4 magnetic nanocomposite was analyzed utilizing various techniques including FTIR, EDX, FESEM, XRD, BET, CHNSO, and TGA. The results displayed that the resulting nanocomposite with maximum adsorption capacity (Qmax) successfully removed the acetamiprid pesticide from polluted water under optimal conditions such as pH of 7.00, 5.00 mg of adsorbent, 20.0 min duration, and 400 mg/L acetamiprid concentration. According to the linear Langmuir isotherm, the Qmax of the biosorbent was 833 mg/g. The experimental adsorption data fitted well with Temkin's nonlinear isotherm model. The adsorption kinetic data were closely related to the Weber-Morris intraparticle diffusion nonlinear model. After three repetitive cycles, CMT-g-P3AP/ZnO@Fe3O4 can be outstandingly renewed and recycled without significant reduction in its adsorption efficacy, as evidenced by the adsorption-desorption experiments. In addition, the CMT-g-P3AP/ZnO@Fe3O4 displayed the good antibacterial activity against E. coli and S. aureus.


Assuntos
Antibacterianos , Neonicotinoides , Poluentes Químicos da Água , Óxido de Zinco , Poluentes Químicos da Água/química , Óxido de Zinco/química , Adsorção , Antibacterianos/química , Neonicotinoides/química , Tragacanto/química , Nanocompostos/química , Purificação da Água/métodos , Praguicidas/química
2.
Mikrochim Acta ; 191(10): 582, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39245663

RESUMO

A novel colorimetric approach specifically designed to effectively identify the presence of 3-aminophenol (3-AP) in environmental water is introduced. Briefly, a nitrogen-doped carbon-supported cobalt nanozyme (Co@CN-1) was synthesized and utilized to improve the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of peroxymonosulfate (PMS). Comparative catalytic reactions confirmed that the performance of PMS as an activator exceeds that of hydrogen peroxide catalytically by a factor of 3.5. The catalytic reaction parameters underwent optimization, further resulting in the derivation of a linear detection equation for 3-AP, expressed as inhibition rate (IR%) = 3.35[3-AP]-4.36 (0-20 µM, R2 = 0.994) and IR% = 1.43[3-AP] + 31.87 (20-36 µM, R2 = 0.992), with the limit of detection (LOD) of 2.84 µM. The linear relationship between 3-AP concentration and the conversion of color to grayscale value (GSV) was established by smartphones, expressed as GSV = 1.28[3-AP] + 147.10 (R2 = 0.972). Density functional theory calculations revealed that Co acts as the preferred active site for donating electrons in PMS activation. This work provides a rapid and accurate approach for monitoring 3-AP concentration, enabling real-time analysis and potentially contributing to environmental and ecological studies.

3.
Molecules ; 24(19)2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547514

RESUMO

Composite nanoparticles were used in solid phase micro membrane tip extraction and capillary electrophoresis to determine phenol and p-amino-phenol in wastewater. The optimized conditions were 100 g/L concentration, 40 min contact time, 11 pH, 5 mg/mL nanoparticles amounts, 60 min desorption time, 9 desorption pH and 298 K temperature. Capillary electrophoresis conditions were phosphate buffer (15 mM, pH 7.0) background electrolyte, 18 kV applied voltage, 214 nm UV detection, 30 s sample loading at 23 ± 1 °C. The maximum percent uptakes of p-amino-phenol and phenol were 80.0 and 85.0%. High ratio recoveries of p-amino-phenol and phenol from nanomaterial were 99.0 and 98. Consequently, the actual extractions of p-amino-phenol and phenol from wastewater were 79.2 and 83.30 percent. The migration times of phenol and p-amino-phenol and were 9.0 and 12.0 min. The detection limits of phenol and p-amino-phenols were 0.1 and 0.2 µg/L after extraction and CE. Therefore, this combination of solid phase micro membrane tip extraction and capillary electrophoresis may be considered as the ideal one for monitoring of toxic phenol and p-amino-phenol in water sample.


Assuntos
Eletroforese Capilar/métodos , Fenol/química , Microextração em Fase Sólida/métodos , Águas Residuárias/química , Aminofenóis/química
4.
Bioorg Med Chem ; 21(22): 7146-54, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24080101

RESUMO

Identification of novel and selective anticancer agents remains an important and challenging goal in pharmacological research. Choline kinase (ChoK) is the first enzyme in the CDP-choline pathway that synthesizes phosphatidylcholine (PC), the major phospholipid in eukaryotic cell membranes. In the present paper, a new family of non-symmetrical monocationic compounds is developed including a 3-aminophenol moiety, bound to 4-(dimethylamino)- or 4-(pyrrolidin-1-yl)pyridinium cationic heads through several linkers. The most promising compounds in these series as ChoK inhibitors are 3f and 4f, while compounds 3c, 3d and 4c are the better antiproliferative agents. The analysis of the biological data observed in the described series of compounds mays represents a platform for the design of more active molecules.


Assuntos
Colina Quinase/antagonistas & inibidores , Inibidores Enzimáticos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Colina Quinase/metabolismo , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Hemicolínio 3/química , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117470, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476649

RESUMO

In this work, we presented a sensitive and selective colorimetric and fluorescent dual-readout sensor based on Griess assay for nitrite (NO2-) detection under acidic condition. The sensor system was constituted of acid-resistant carbon quantum dots (CQDs) and 3-aminophenol (3-Aph) with acidic condition regulated using HCl. During the sensing procedure, reaction of 3-Aph and NO2- under acidic condition can yield a yellow-colored azoic compound (AZO), which gives the colorimetric readout; meanwhile, the fluorescence of CQDs (fluorescence reporter) quenched due to the strong absorption of AZO, leading to fluorescent readout. Wherein, CQDs were synthesized via hydrothermal method through using polyacrylamide as precursor and characterized by AFM, XRD and XPS. Under the optimized condition, the sensor exhibit broad linear relationships towards NO2- in the range of 10 to 100 nM and 2.5 to 100 µM, with practical detection limits of 10 nM and 2.5 µM for the fluorescent and colorimetric readout, respectively. And the sensor displayed excellent capability of selectivity according to interferences study. Furthermore, testing of sprouts, bacon and ham sausage real samples demonstrated good recoveries and reproducibility of the sensor system. All these results suggested the presented colorimetric and fluorescent dual-readout sensor can be a promising candidate for the NO2- detection in real applications.

6.
Food Chem ; 311: 125999, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864185

RESUMO

A method based on solid-phase extraction (SPE) coupled with high-performance liquid chromatography (HPLC) was developed to determine the content of 4-chlorophenoxy acetic acid (PCPA), naphthylacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) in green bell peppers. A molecularly imprinted 3-aminophenol-glyoxal-urea resin (MIAGUR) was first synthesized as a specific SPE adsorbent, which exhibited special selectivity and multiple adsorption interactions including hydrogen bonding and π-π interactions. The quantities of PCPA, NAA and 2,4-D in green bell peppers from 20 samples scattered throughout Baoding city (Hebei province, China) were determined using the proposed method. The results suggested that the use of PCPA, NAA and 2,4-D in green bell peppers from Baoding's markets is almost in fair. Moreover, MIAGUR-SPE-HPLC is suitable for the specific simultaneous monitoring of PCPA, NAA, and 2,4-D in green bell peppers and has potential applications in determination of PCPA, NAA, and 2,4-D of other plant products.


Assuntos
Capsicum/metabolismo , Impressão Molecular , Reguladores de Crescimento de Plantas/análise , Ureia/química , Aminofenóis/química , Capsicum/química , Cromatografia Líquida de Alta Pressão/métodos , Glioxal/química , Interações Hidrofóbicas e Hidrofílicas , Reguladores de Crescimento de Plantas/isolamento & purificação , Extração em Fase Sólida
7.
Environ Technol ; 36(17): 2255-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25741590

RESUMO

Aminophenols (AP) are synthetic intermediates in pharmaceutical, photographic and chemical dye industry. They can be released into the environment from wastewater and can react during water treatment processes. Therefore, it was interesting to study the oxidation of AP with chlorine and monochloramine in aqueous solution. In particular, the chlorination and monochloramination of 3-aminophenol (3AP) were investigated, and the formation of first by-products and kinetic rates were determined. The chlorination rate was 3.6 × 10(5) times greater than the monochloramination rate at pH 8.6. Two reaction pathways can explain the variation of the monochloramination apparent rate constant with pH. The first one was an electrophilic substitution of Cl(+) on the aromatic ring of the non-ionized 3AP, leading to the formation of chloroaminophenol, with an individual rate constant of 6.7 × 10(2) M(-1) h(-1). The second reaction pathway was a monochloramine attack on the amino group of 3AP catalyzed at acidic pH with an individual rate constant of 9.2 × 10(9) × M(-2) × h(-1).


Assuntos
Aminofenóis/química , Cloraminas/química , Cloro/química , Poluentes Químicos da Água/química , Aminação , Halogenação , Cinética , Oxirredução , Purificação da Água
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