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1.
Food Chem ; 374: 131712, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34920407

RESUMO

Metal-organic frameworks (MOFs) has excellent adsorption performance, herein, three kinds of common MOFs were used for the adsorption of sulfamethazine (SM2) in milk, then enzyme-linked immunosorbent assay (MOF-ELISA) was established. Firstly, NH2-UiO-66, NH2-MIL-101, and ZIF-8 were successfully prepared and their adsorption characteristics for SM2 were investigated. The kinetic models of the three MOFs were more in line with the pseudo-second-order adsorption kinetics, and the saturated adsorption capacity of NH2-UiO-66, NH2-MIL-101, and ZIF-8 for SM2 at 298 K were 139.64, 29.98, and 36.5 mg/g, respectively. Using three different MOFs as adsorbents, the pretreatment of milk samples could be completed within 1 h, the half inhibitory concentrations (IC50) of MOF-ELISA were 1.26, 1.86 and 2.74 ng/mL, the limit of detections (LOD) were 0.05, 0.12, and 0.19 ng/mL and the recovery rate were from 82.30% to 105.62% with the intra-day coefficient of variations (CVs) below 5.81% and inter-day CVs below 7.21%. Detection results showed good correlations with LC-MS/MS (R2 > 0.99), indicated that MOFs could effectively eliminate the interference of sample matrix, and has the potential to become a general pretreatment method for the detection of various matrices residues in food safety monitoring.


Assuntos
Estruturas Metalorgânicas , Adsorção , Animais , Cromatografia Líquida , Ensaio de Imunoadsorção Enzimática , Leite , Ácidos Ftálicos , Sulfametazina , Espectrometria de Massas em Tandem
2.
Chemosphere ; 286(Pt 1): 131579, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34311399

RESUMO

Boron-doped diamond electrodes have been employed for the removal of sulfamethazine (SMZ) from water by electrochemical activation of persulfate (EO/BDD-PS). A set of experiments with a central composite design (CCD) was conducted to optimize the operating parameters such as persulfate dose, solution pH, and current density by response surface methodology (RSM). The experimental results indicated a rapid degradation of SMZ even at high initial concentrations. For instance, complete degradation of 50 mg L-1 of SMZ was attained after 15 min at the optimum operating conditions (persulfate loading = 0.40 g L-1, pH = 4, and current density = 21 mA cm-2). The oxidation mechanism of EO/BDD-PS process was studied based on the reactive oxidant species (ROS) revealing that both (OH) and contributed to the degradation of SMZ in the EO/BDD-PS system. Furthermore, the oxidation pathway has been proposed by the suspect screening and tandem mass spectrometry analysis. The performance of EO/BDD-PS showed faster SMZ degradation than electro-Fenton and anodic oxidation processes using the same BDD electrochemical reactor under the same conditions. Furthermore, we provided a cost estimation study revealing that a full-scale application of the EO/BDD-PS system for the treatment of similar contaminated water costs about $2.23 m-3.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Dioxóis , Eletrodos , Oxirredução , Sulfametazina , Poluentes Químicos da Água/análise
3.
J Hazard Mater ; 423(Pt A): 127003, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34474367

RESUMO

The individual and combined toxicity of antibiotics and nanoplastics in marine organisms has received increasing attention. However, many studies have been mostly focused on the impacts on the directly exposed generation (F0). In this study, intergenerational effects of sulfamethazine (SMZ) and nanoplastic fragments (polystyrene, PS) on the growth and the gut microbiota of marine medaka (Oryzias melastigma) were investigated. The results showed that parental exposure to dietary SMZ (4.62 mg/g) alone and PS (3.45 mg/g) alone for 30 days decreased the body weight (by 13.41% and 34.33%, respectively) and altered the composition of gut microbiota in F1 males (two months after hatching). Interestingly, parental exposure to the mixture of SMZ and PS caused a more modest decrease in the body weight of F1 males than the PS alone (15.60% vs 34.33%). The hepatic igf1 level and the relative abundance of the host energy metabolism related phylum Bacteroidetes for the SMZ + PS group were significantly higher than those for the PS group (igf1, increased by 97.1%; Bacteroidetes, 2.876% vs 0.375%), suggesting that the parentally derived mixture of SMZ and PS might influence the first microbial colonization of gut in a different way to the PS alone. This study contributes to a better understanding of the long-term risk of antibiotics and nanoplastics to marine organisms.


Assuntos
Microbioma Gastrointestinal , Oryzias , Poluentes Químicos da Água , Animais , Masculino , Microplásticos , Sulfametazina/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Talanta ; 237: 122920, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736657

RESUMO

Antibiotic residues in aquatic environments have attracted wide attention. Considering the impacts on the ecosystem and human health, it is urgent to develop a rapid method for detecting antibiotic residues in the environment. In this work, a nanoscale lanthanide metal-organic framework Eu(TATB) with a stable red luminescence in aqueous solution is synthesized by the microemulsion method. Sulfamethazine (SMZ) is frequently most used in veterinary medicine as one of sulfonamides. Eu(TATB) can be used for sensitively and rapidly specific recognition of SMZ with low detection limit (0.67 µM) and eminent recyclability. In addition, a paper-based visual system for point-of-care (POC) monitoring SMZ is devised by both using filter paper embedded with Eu(TATB) and our developed portable smartphone-involved imaging cassette. The naked eyes can observe that the red luminescence of the paper sensor gradually fades away at the presence of SMZ. This provides a reliable and effective method for on-site detection of sulfonamide antibiotics in the field of environmental monitoring.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Ecossistema , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Smartphone , Sulfametazina
5.
Sensors (Basel) ; 21(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34640926

RESUMO

Sulfamethazine (SMZ) as a broad antibiotic is widely used in livestock and poultry. However, the abuse of SMZ in livestock feed can lead to SMZ residues in food and the resistance of bacteria to drugs. Thus, a method for the detection of SMZ in food is urgently needed. In this study, quantum dot (QD) nanobeads (QBs) were synthesized by encapsulating CdSe/ZnS QDs using a microemulsion technique. The prepared QBs as signal probes were applied in lateral flow immunoassay (LFIA) for the detection of SMZ in chicken and milk. Our proposed method had limits of detection of 0.1138-0.0955 ng/mL and corresponding linear ranges of 0.2-12.5, 0.1-15 ng/mL in chicken and milk samples, respectively. The recovery of LFIA for the detection of SMZ was 80.9-109.4% and 84-101.6% in chicken and milk samples, respectively. Overall, the developed QBs-LFIA had high reliability and excellent potential for rapid and sensitive screening of SMZ in food.


Assuntos
Pontos Quânticos , Animais , Galinhas , Imunoensaio , Leite/química , Reprodutibilidade dos Testes , Sulfametazina/análise
6.
Sci Rep ; 11(1): 17953, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504157

RESUMO

A new series of nucleosides, moieties, and Schiff bases were synthesized from sulfadimidine. Infrared (IR), 1HNMR, 13C NMR, and mass spectrometry techniques and elemental analysis were employed to elucidate the synthesized compounds. The prepared analogues were purified by different chromatographic techniques (preparative TLC and column chromatography). Molecular docking studies of synthesized compounds 3a, 4b, 6a, and 6e demonstrated the binding mode involved in the active site of DNA gyrase. Finally, all synthesized compounds were tested against selected bacterial strains. The most effective synthesized compounds against S. aureus were 3a, 4d, 4b, 3b, 3c, 4c, and 6f, which exhibited inhibition zones of inhibition of 24.33 ± 1.528, 24.67 ± 0.577, 23.67 ± 0.577, 22.33 ± 1.528, 18.67 ± 1.528 and 19.33 ± 0.577, respectively. Notably, the smallest zones were observed for 4a, 6d, 6e and 6g (6.33 ± 1.528, 11.33 ± 1.528, 11.67 ± 1.528 and 14.66 ± 1.155, respectively). Finally, 6b and 6c gave negative zone values. K. pneumoniae was treated with the same compounds and the following results were obtained. The most effective compounds were 4d, 4c, 4b and 3c, which showed inhibition zones of 29.67 ± 1.528, 24.67 ± 0.577, 23.67 ± 1.155 and 19.33 ± 1.528, respectively, followed by 4a and 3d (15.33 ± 1.528 for both), while moderate results (13.67 ± 1.155 and 11.33 ± 1.528) were obtained for 6f and 6g, respectively. Finally, 6a, 6b, 6c, 3a, and 3b did not show any inhibition. The most effective compounds observed for the treatment of E. coli were 4d, 4b, 4c, 3d, 6e and 6f (inhibition zones of 26.33 ± 0.577, 21.67 ± 1.528, 21.67 ± 1.528, 19.67 ± 1.528, 17.67 ± 1.155 and 16.67 ± 1.155, respectively). Compounds 3b, 3c, 6a, 6c, and 6g gave moderate results (13.67 ± 1.528, 12.67 ± 1.528, 11.33 ± 0.577, 15.33 ± 1.528 and 12.67 ± 1.528, respectively), while 6b showed no effect. The MIC values against S. aureus ranged from 50 to 3.125 mg, while those against E. coli and K. pneumoniae ranged from 50 to 1562 mg. In vitro, the antibacterial effects were promising. Further research is required to study the in vivo antibacterial effects of these compounds and determine therapeutic doses.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Simulação de Acoplamento Molecular/métodos , Nucleosídeos/química , Nucleosídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Sulfametazina/análogos & derivados , Domínio Catalítico , DNA Girase/metabolismo , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana/métodos , Nucleosídeos/síntese química , Bases de Schiff/química , Relação Estrutura-Atividade
7.
Ecotoxicol Environ Saf ; 226: 112820, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34571422

RESUMO

Antibiotics and nanoplastics are two prevalent pollutants in oceans, posing a great threat to marine ecosystems. As antibiotics and nanoplastics are highly bioconcentrated in lower trophic levels, evaluating their impacts on marine organisms via dietary exposure route is of great importance. In this study, the individual and joint effects of dietborne sulfamethazine (SMZ) and nanoplastic fragments (polystyrene, PS) in marine medaka (Oryzias melastigma) were investigated. After 30 days of dietary exposure, 4.62 mg/g SMZ decreased the Chao1 index (60.86% for females and 26.85% for males) and the Shannon index (68.95% for females and 65.05% for males) and significantly altered the structure of gut microbial communities in both sexes. The female fish exposed to 4.62 mg/g SMZ exhibited higher intestinal sod (43.5%), cat (38.5%) and gpx (39.6%) transcripts, indicating oxidative stress in the gut. PS alone at 3.45 mg/g slightly altered the composition of the gut microbiota. Interestingly, the mixture of SMZ and PS caused more modest effects on the gut microbiota and intestinal antioxidant physiology than the SMZ alone, suggesting that the presence of PS might alleviate the intestinal toxicity of SMZ in a scenario of dietary co-exposure. This study helps better understand the risk of antibiotics and nanoplastics to marine ecosystems.


Assuntos
Microbioma Gastrointestinal , Oryzias , Poluentes Químicos da Água , Animais , Ecossistema , Feminino , Masculino , Microplásticos , Estresse Oxidativo , Sulfametazina/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Poult Sci ; 100(10): 101378, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34391174

RESUMO

Rapid detection of antibiotic residues in duck meat is of great significance for strengthening food safety and quality supervision of duck meat and fighting against inferior products in the duck meat market. The objective of the current paper was to evaluate the potential of synchronous fluorescence spectroscopy (SFS) coupled with chemometric methods for the rapid detection of sulfamethazine (SM2) and ofloxacin (OFL) residues in duck meat.The SFS spectral data from duck meat containing different concentrations of SM2 and OFL were preprocessed by baseline offset. The detection conditions, including the adding amounts of ß-mercaptoethanol solution and o-phthalaldehyde solution, as well as the reaction time, were optimized by a single factor experiment for obtaining a better detection effect, and their optimal values were 400 µL , 25 µL , and 40 min, respectively. By comparing 2 chemometric models based on peak-height algorithm and peak-area algorithm, the prediction model based on peak-height algorithm was a better quantitative model with correlation coefficient for the prediction set (Rp) of 0.9031 and 0.9981, the root mean error for the prediction set (RMSEP) of 7.9509 and 0.5267 mg/kg, recovery of 81.7 to 155.1% and 96.4 to 111.2%, and relative standard deviation (RSD) of 4.1 to 6.7% and 2.9 to 6.8% to predict SM2 and OFL residues in duck meat, respectively. Overall, the results of this investigation showed that SFS technique was an effective and rapid tool for the detection of SM2 and OFL residues in duck meat.


Assuntos
Ofloxacino , Sulfametazina , Animais , Galinhas , Patos , Carne/análise , Espectrometria de Fluorescência/veterinária
9.
Water Res ; 202: 117451, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34330026

RESUMO

In this work, the novel application of chalcopyrite (CuFeS2) for sodium percarbonate (SPC) activation towards sulfamethazine (SMT) degradation was explored. Several key influencing factors like SPC concentration, CuFeS2 dosage, reaction temperature, pH value, anions, and humic acid (HA) were investigated. Experimental results indicated that SMT could be effectively degraded in the neutral reaction media by CuFeS2/SPC process (86.4%, 0.054 min-1 at pH = 7.1). The mechanism of SPC activation by CuFeS2 was elucidated, which was discovered to be a multiple reactive oxygen species (multi-ROS) process with the coexistence of hydroxyl radical (•OH), carbonate radical (CO3•-), superoxide radical (O2•-), and singlet oxygen (1O2), as evidenced by quenching experiments and electron spin resonance (ESR) tests. The generated •OH via the traditional heterogeneous Fenton-like process would not only react with carbonate ions to yield other ROS but also involve in SMT degradation. The abundant surface-bound Fe(II) was deemed to be the dominant catalytic active sites for SPC activation. Meanwhile, it was verified that the reductive sulfur species, the interaction between Cu(I) and Fe(III) as well as the available O2•- derived from the activation of molecular oxygen and the conversion of •OH favored the regeneration of Fe(II) on CuFeS2 surface. Furthermore, the degradation intermediates of SMT and their toxicities were evaluated. This study presents a novel strategy by integrating transition metal sulfides with percarbonate for antibiotic-contaminated water treatment.


Assuntos
Sulfametazina , Poluentes Químicos da Água , Carbonatos , Cobre , Compostos Férricos , Peróxido de Hidrogênio , Oxirredução , Poluentes Químicos da Água/análise
10.
J Hazard Mater ; 417: 126022, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229407

RESUMO

The migration risk of antibiotic and antibiotic resistance genes (ARGs) have attracted lots of attentions due to their potential threaten to public health. Strategies to reduce their vertical mobilization risk are urgently required for groundwater safety and human health. Biochar enjoys numerous interests due to its excellent sorption affinity. However, little was known about the efficacy of biochar amendment in impeding the vertical mobilization of antibiotic and ARGs. To fill this gap, a column study was carried out to investigate biochar-induced variations in the leaching behavior of dissolved organic matter (DOM), sulfamethazine (SMZ) and ARGs. Results showed that biochar addition enhanced DOM export from soil, changed its composition and impeded the vertical transport of SMZ. Biochar amendment could effectively decrease the occurrence of extracellular and intracellular sul2 in soil and impede its vertical transportation, however, it did not work out with sul1 gene. Structural equation modeling analysis demonstrated that the abundance of sul2 was significantly controlled by SMZ concentration, while the primary drivers of sul1 were SMZ concentration and DOM content. These results indicated the failure in inhibiting the vertical transfer of sul1 under biochar amendment and highlighted the important role of DOM in the leaching of soil ARGs.


Assuntos
Solo , Sulfametazina , Carvão Vegetal , Resistência Microbiana a Medicamentos/genética , Humanos
11.
Chemosphere ; 278: 130420, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34126678

RESUMO

Sulfamethazine is one of the most frequently used sulfonamides in the poultry farming industry. However, the residue accumulation, distribution, and depletion of sulfamethazine (SMZ) and its metabolite, N4-acetylsulfamethazine (NAS), in poultry waste (manure and feathers) have yet to be evaluated. In our study, the residue levels of SMZ and NAS in manure and feathers are determined by liquid chromatography tandem mass spectrometry. Furthermore, the distribution, depletion, and withdrawal period of SMZ and NAS in manure and feathers are investigated under field conditions. Results show that high concentrations (0.7-43.3 mg/kg for SMZ, and 0.22-22.4 mg/kg for NAS) of SMZ and NAS residues remain in manure and feathers even when SMZ has been used. The withdrawal periods of SMZ and NAS in feathers are 97.0 d and 28.0 d, respectively. In manure, the withdrawal period is 18.2 d and 8.0 d, respectively. Poultry waste is a possible major reentry way of SMZ into the food chain and the environment.


Assuntos
Galinhas , Sulfametazina , Animais , Cromatografia Líquida , Aves Domésticas , Sulfametazina/análogos & derivados
12.
J Hazard Mater ; 417: 125908, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-33984789

RESUMO

The increasing amount of antibiotics entering the environment through manure usage and sludge application from wastewater treatment plants (WWTP) attracts much concern due to their potential threat to ecological security and human health. When biochar, a soil and water amendment, is introduced into the soil for remediation, the antibiotics are usually co-present with the biochar colloids (BC) or pre-accumulated in soils. However, little is known about the effect of antibiotics on the behavior of BC. Column experiments were conducted at three different pH values to study the effect of sulfamethazine (SMT) or ciprofloxacin (CIP) on BC transport. Under certain conditions (co-present in the influent and pre-sorbed on quartz sand), large numbers of cation and zwitterion forms of the less mobile CIP at pH 5 and 7 led to less negatively-charged surface of BC and quartz sand, resulted in higher BC retention compared to the highly mobile SMT. The decrease in BC transport became more significant with a higher amount of SMT or CIP pre-sorption. Therefore, when biochar is applied into soils polluted by antibiotics, the pH-dependency and the loading amount of antibiotics in soil matrix should be paid attention to as they might affect the transport of BC and the related facilitated-contaminants transport.


Assuntos
Ciprofloxacina , Sulfametazina , Adsorção , Carvão Vegetal , Coloides , Humanos , Porosidade , Solo
13.
Int J Nanomedicine ; 16: 2751-2759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859476

RESUMO

Purpose: Sulfamethazine (SMZ) exposed in the environment can enter the human body through the food chain and pose a serious threat to human health. Therefore, it is important to develop a rapid and sensitive method for detecting SMZ in environmental samples. In order to fastly and quantitatively detect SMZ in environmental samples, we developed a label-free fluorescent aptasensor based on specific aptamer (SMZ1S) and fluorescence resonance energy transfer (FRET) between gold nanoparticles (AuNPs) and rhodamine B (RhoB). Methods: In the absence of SMZ, SMZ1S was adsorbed on the surface of AuNPs, which led to dispersion of the AuNPs in high concentration saline solution, thus effectively quenching the fluorescence of RhoB. With the increase of the SMZ concentration, the specific binding of SMZ1S and SMZ led to the aggregation of AuNPs in the presence of NaCl, which reduced the quenching of RhoB fluorescence and increased the fluorescence intensity. The sensitivity and linearity curve of the label-free fluorescent aptasensor were determined with different concentrations of sulfamethazine standard solutions. The specificity of this fluorescent aptasensor was determined by replacing sulfamethazine with different antibiotics. In addition, the actual water and soil samples were spiked and recovered. Results: Under optimized conditions, the proposed fluorescent aptasensor demonstrated a good linear detection of SMZ in binding buffer from 1.25 ng mL-1 to 40 ng mL-1 and the limit of detection was 0.82 ng mL-1. The spiked recoveries for SMZ were 94.4% to 108.8% with a relative standard deviation of 1.8-10.3% in water and soil samples, respectively. Conclusion: The label-free fluorescent aptasensor investigated in the current study is a promising tool to detect and quantify SMZ in water and soil samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Sulfametazina/análise , Difusão Dinâmica da Luz , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Solo/química , Espectrometria de Fluorescência , Coloração e Rotulagem , Água/química
14.
Braz J Biol ; 82: e238673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729384

RESUMO

Coccidiosis remains one of the major problems in poultry all over the world. Very limited data on anticoccidial drugs in wild pigeons is available. The current study was aimed to understand the comparative efficacy of sulfadimidine, amprolium and triquen in wild pigeons of Dir district, Pakistan suffering from coccidiosis. The faecal matter of wild pigeons were purchased from the local market for coccidian infection. Results revealed that 88.8% (16/18) were found infected with Eimeria spp. Three positive groups were treated with sulfadimidine (0.2mg/L), amprolium (25mg/L) and triquen. Sulfadimidine was most effective (45%) followed by amprolium (44.6%) while triquen (24.0%) showed less effectiveness against coccidiosis in pigeons. Number of oocysts were 79, 81 and 80 before treatment and 60, 44 and 44 after treatment with sulfadimidine, amprolium and triquen respectively. This study showed that sulphadimidine, amprolium and triquen could not significantly reduce the coccidiosis in pigeons. Further studies are required to clear the mechanism of anti-coccidial drugs in wild pigeons.


Assuntos
Amprólio , Coccidiose , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Columbidae , Paquistão , Sulfametazina
15.
Chemosphere ; 277: 130305, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33773319

RESUMO

A novel composite (CNTs-Fe3O4) was synthesized by a ball-milling strategy and characterized by BET, SEM, FTIR, XRD and VSM. The as-fabricated CNTs-Fe3O4 was used to remove six sulfonamides by a Fenton degradation process, including sulfanilamide (SAM), sulfamerazine (SMR), sulfadimethoxine (SMX), sulfadiazine (SDZ), sulfamethazine (SMT) and sulfametoxydiazine (SMD). The degradation behaviors of six sulfonamides in CNTs-Fe3O4/H2O2 system and the relationship between molecular structure of sulfonamides and their degradation behaviors were investigated systematically. Batch experimental results showed that the as-fabricated CNTs-Fe3O4 had excellent Fenton catalytic activity for the degradation of sulfonamides due to its unique porous structure and the good combination mode of CNTs with Fe3O4 particles. The first-order kinetic mode could better describe the degradation behaviors of six sulfonamides in CNTs-Fe3O4/H2O2 system, and the degradation rate constant could be ordered as: SAM < SMT < SDZ < SMR < SMD < SMX. The quantitative relationship between the Mulliken charge of sulfonamides (x) and their degradation rate constant (y) in CNTs-Fe3O4/H2O2 system could be described as: y = - 28.719x + 15.67 (R2 = 0.957). Finally, the possible synthesis mechanisms of CNTs-Fe3O4 and the degradation mechanisms of sulfonamides in CNTs-Fe3O4/H2O2 system was proposed.


Assuntos
Peróxido de Hidrogênio , Sulfonamidas , Catálise , Sulfametazina , Sulfanilamida
16.
Environ Res ; 195: 110814, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33524329

RESUMO

This work focuses on studying the efficacy of three different by-products to adsorb three antibiotics (sulfadiazine, SDZ; sulfamethazine, SMT; sulfachloropyridazine, SCP). These antibiotics can be considered pollutants of the environment when they reach water, as well as in cases where they are spread on soils through irrigation or contained in sewage sludge or livestock manure. In this study, batch-type adsorption/desorption experiments were performed for each of the three sulfonamides, adding 7 different concentrations of the antibiotics, going from 1 to 50 µmol L-1, and with contact time of 24 h. The results indicate that pine bark is the most efficient bioadsorbent among those studied, as it adsorbs up to 95% of the antibiotics added, while desorption is always less than 11%. However, for "oak ash" and mussel shell the adsorption is always lower than 45 and 15%, respectively, and desorption is high, reaching up to 49% from "oak ash" and up to 81% from mussel shell. Adsorption data showed good fitting to the Linear and Freundlich models, with R2 values between 0.98 and 1.00 in both cases. Kd and KF adsorption parameters showed similar values for the same sorbent materials but were much higher for pine bark than for the other two bioadsorbents. The Freundlich's n parameter showed values in the range 0.81-1.28. The highest KF values (and therefore the highest adsorption capacities) were obtained for the antibiotic SCP in pine bark. Pine bark showed the highest capacity to adsorb each of the antibiotics, increasing as a function of the concentration added. When the concentration of sulfonamide added was 50 µM, the amounts adsorbed were 780 µmol kg-1 for SDZ, 890 µmol kg-1 for SMT, and 870 µmol kg-1 for SCP. "Oak ash" and mussel shell have low adsorption capacity for all three sulfonamides, showing values always lower than 150 µmol kg-1 (oak ash) and 20 µmol kg-1 (mussel shell) when a concentration of 50 µmol L-1 of antibiotic is added. The results of this study could aid to make an appropriate management of the by-products studied, in order to facilitate their valorization and recycling in the treatment of environmental compartments polluted with sulfonamide antibiotics.


Assuntos
Bivalves , Quercus , Poluentes do Solo , Sulfacloropiridazina , Adsorção , Animais , Casca de Planta/química , Porosidade , Solo , Poluentes do Solo/análise , Sulfadiazina , Sulfametazina
17.
Water Res ; 194: 116915, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33607387

RESUMO

In this study, visible light (VL) was adopted for permanganate (PM) activation without additional catalyst, where sulfamethazine (SMT) was selected as the probe compound. Experiment results showed that the VL/PM system can effectively degrade SMT through pseudo-first-order reaction kinetics. Influencing factors including PM dosage, solution pH, humid acid (HA) and coexisting anions (CO32-, SO42-, Cl- and NO3-) which affect SMT photo-degradation were also examined. Pyrophosphate (PP) had an inhibitory effect on SMT degradation due to the complexation of PP with Mn (III). Electron spin resonance (ESR) spectrometry and UV-Vis spectrophotometer proved that VL can activate PM to generate ·O2- and Mn (III) reactive species. Furthermore, based on the active site prediction, intermediates identification and Density Functional Theory (DFT) calculation, two main degradation pathways involving SMT molecular rearrangement and cleavage of S-N bond were proposed. Moreover, the energy barriers of the two degradation pathways were also calculated. This study offers a novel approach for aqueous SMT removal and deepens our understanding of the degradation mechanism of SMT through DFT calculation, which hopes to shed light on the future development of VL/PM treatment.


Assuntos
Sulfametazina , Poluentes Químicos da Água , Peróxido de Hidrogênio , Luz , Compostos de Manganês , Óxidos
18.
Environ Pollut ; 276: 116692, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592446

RESUMO

Photodegradation is a major elimination route of many pharmaceutically active compounds (PhACs) in natural surface waters, yet their photolytic behavior in estuarine waters with salinity gradient change is largely unknown. Herein, sulfamethazine and carbamazepine were taken as representative PhACs to explore the photolytic kinetic differences in Qinzhou Bay estuarine water samples collected from upper to lower reaches. Rapid photodegradation of sulfamethazine was found in lower estuarine water relative to upstream estuarine water; whereas for carbamazepine, photolytic rate was inversely proportional to the salinity of estuarine waters. Experiments with extracted estuarine dissolved organic matter (E-DOM) imply that the multivariate effects of triplet-excited E-DOM (3E-DOM∗) and halide ions are responsible for the enhancement photolysis of sulfamethazine. Radical scavenging experiments suggest that the photolysis enhancement can be ascribed to the contribution of reactive halogen species (RHS), while their contribution to carbamazepine is negligible and 3E-DOM∗ is the dominant reactive species for its photodegradation. This indicates that the reactivity differences with RHS and 3DOM∗ affect the photolytic kinetics of PhACs from upper estuarine waters to lower reaches, which is also supported by a good linear relationship between the ratios of photolytic rates for ten PhACs in E-DOM solution with/without halides and the ratios of the reactivity of these pollutants with RHS and 3DOM∗. These findings show that the different reactivity of PhACs with 3E-DOM∗ and RHS influences the photolytic kinetics in estuarine waters with different salinity, and highlights the photochemical behavior of organic micropollutants from upstream to downstream estuarine waters.


Assuntos
Halogênios , Poluentes Químicos da Água , Cinética , Fotólise , Sulfametazina
19.
J Hazard Mater ; 413: 125286, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33592488

RESUMO

Microplastics were reported to adsorb antibiotics and may modify their effects on soil systems. But there has been little research investigating how microplastics may affect the toxicities of antibiotics to microbes under future climate conditions. Here, we used a free-air CO2 enrichment system to investigate the responses of soil microbes to sulfamethazine (SMZ, 1 mg kg-1) in the presence of polystyrene microplastics (PS, 5 mg kg-1) at different CO2 concentrations (ambient at 380 ppm and elevated at 580 ppm). SMZ alone decreased bacterial diversity, negatively affected the bacterial structure and inter-relationships, and enriched the sulfonamide-resistance genes (sul1 and sul2) and class 1 integron (intl1). PS, at both CO2 conditions, showed little effect on soil bacteria but markedly alleviated SMZ's adverse effects on bacterial diversity, composition and structure, and inhibited sul1 transmission by decreasing the intl1 abundance. Elevated CO2 had limited modification in SMZ's disadvantages to microbial communities but markedly decreased the sul1 and sul2 abundance. Results indicated that increasing CO2 concentration or the presence of PS affected the responses of soil microbes to SMZ, providing new insights into the risk prediction of antibiotics under future climate conditions.


Assuntos
Microbiota , Solo , Antibacterianos/toxicidade , Dióxido de Carbono/análise , Microplásticos , Plásticos , Poliestirenos , Microbiologia do Solo , Sulfametazina/toxicidade
20.
Anal Methods ; 13(7): 910-917, 2021 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-33511972

RESUMO

Determination and sensing of antibiotics in dairy products are the biggest challenges in the world. In continuation of our earlier study, a facile and novel determination method for the detection of sulfamethazine (SMZ) in cow milk has been developed using a glassy carbon electrode modified with graphene oxide decorated with Cu-Ag core-shell nanoparticles. The Cu-Ag core-shell nanoparticles and graphene oxide were synthesized and characterized via different techniques such as TEM, SEM, XRD and FTIR. The as-synthesized Cu-Ag core-shell nanoparticles were used for the decoration of the glassy carbon electrode modified with graphene oxide. The electroanalytical measurements including cyclic voltammetry and square wave voltammetry were performed and compared with HPLC, which was utilized for the determination of SMZ in cow milk. The experimental conditions were optimized to obtain a well-defined response signal. The concentration linear range was 10-1000 µM and the limit of detection was 0.46 µM for S/N = 3. The obtained results show good agreement with HPLC reported data.


Assuntos
Nanopartículas , Sulfametazina , Animais , Antibacterianos , Técnicas Eletroquímicas , Grafite , Limite de Detecção , Leite , Prata
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