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1.
Sci Total Environ ; 753: 141975, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33207448

RESUMO

Tetracyclines (TCs), used as human and veterinary medicines, are the most widely used antibiotics. More than 75% of TCs are excreted in an active form and released into the environment through human and animal urine and feces, causing adverse effects on the ecological system and human health. Few articles review the environmental occurrence and behaviors of TCs, as well as their risks and toxicities. Here, we comprehensively summarized the recent advances on the following important issues: (1) Environmental occurrence of TCs. TCs are used globally and their occurrence in the aquatic environment has been documented, including surface water, groundwater, drinking water, wastewater, sediment, and sludge. (2) Environmental behaviors of TCs, particularly the fate of TCs in wastewater treatment plants (WWTPs). Most WWTPs cannot effectively remove TCs from wastewater, so alternative methods for efficient removal of TCs need to be developed. The latest degradation methods of TCs are summarized, including adsorption, photocatalytic, photochemical and electrochemical, and biological degradations. (3) Toxicities and possible risks of TCs. The toxicological data of TCs indicate that several TCs are more toxic to algae than fish and daphnia. Risk assessments based on individual compound exposure indicate that the risks arising from the current concentrations of TCs in the aquatic environment cannot be ignored.


Assuntos
Poluentes Químicos da Água , Animais , Antibacterianos/toxicidade , Humanos , Medição de Risco , Tetraciclinas/análise , Tetraciclinas/toxicidade , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-32406796

RESUMO

The effect of tetracyclines used for swine food-production (tetracycline and oxytetracycline) on enriched nitrifying bacteria cultures over time was investigated in this study. Short-term exposure assays were performed in different concentrations of each antibiotic, using ammonia oxidizing bacteria (AOB) culture and nitrifying bacteria. The results pointed out a higher inhibitory effect of tetracycline on both bacterial communities. The AOB was more sensitive to antibiotic exposure when compared to the nitrifying culture. Although high antibiotic concentrations were applied, the half maximal inhibitory concentration (IC50) was achieved only for the AOB culture exposed to tetracycline at a concentration of 273 mg L-1. Nonetheless, the long-term exposure assay demonstrated a reduction of the tetracycline inhibition effect against AOB. The exposure to 100 mg L-1 of tetracycline (TC) did not show relevant influence over ammonium conversion efficiency; however, at 128 mg L-1 of TC, the efficiency decreased from 94% to 72%. Further investigation revealed that TC reduced the final effluent quality due to the development of a resistance mechanism by AOB culture against this antibiotic. This mechanism involves increasing the excretion of extracellular polymeric substances (EPS) and soluble microbial products (SMP), which probably increases BOD, and reduces ammonia consumption by the bacterial culture.


Assuntos
Compostos de Amônio/análise , Nitrificação/efeitos dos fármacos , Esgotos/microbiologia , Tetraciclinas/análise , Drogas Veterinárias/análise , Águas Residuárias/microbiologia , Purificação da Água/métodos , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Oxirredução , Esgotos/química , Suínos , Tetraciclinas/toxicidade , Drogas Veterinárias/toxicidade , Águas Residuárias/química
3.
Food Chem ; 326: 126969, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32438229

RESUMO

Biocompatible magnetic molecularly imprinted polymers (BMMIPs) were prepared with Zein for the first time, and were used to enrich tetracycline compounds selectively. Innovative combination of BMMIPs and electrochemistry to obtain lower detection line to satisfy industrial detection demands. Using Zein as the crosslinking agent, the polymers were synthesized on the surface of Fe3O4 particles. The scanning electron microscope, transmission electron microscope and X-ray diffraction technologies were used to characterize BMMIPs. Through optimization, BMMIPs attained large adsorption capacity (236.40 mg/g) with fast kinetics (40 min) and followed the Langmuir isotherm and pseudo-second-order kinetic models. BMMIPs had good recognition ability, the selective factors of oxytetracycline, chlortetracycline, doxycycline were 4.78, 4.23, and 3.39, respectively. Excellent linearity was attained in the range of 0.025-500 µg/mL, with low detection limits and low quantitation limits of 0.025 and 0.083 µg/mL. According to our exploring, BMMIPs was ideal materials for enrichment of tetracycline in complex biological samples.


Assuntos
Materiais Biocompatíveis/química , Contaminação de Alimentos/análise , Leite/química , Impressão Molecular/métodos , Tetraciclinas/análise , Adsorção , Animais , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/isolamento & purificação , Técnicas Eletroquímicas , Análise de Alimentos/métodos , Limite de Detecção , Fenômenos Magnéticos , Nanopartículas de Magnetita/química , Polímeros/química , Tetraciclina/análise , Tetraciclina/química , Tetraciclina/isolamento & purificação , Tetraciclinas/química , Tetraciclinas/isolamento & purificação , Difração de Raios X , Zeína/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-31917650

RESUMO

An ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) based multiclass multi-residue method for the simultaneous analysis of 5 polyether ionophores, 4 tetracycline and 10 sulfonamides in animal and aquaculture fish tissues was developed and validated. Sample extraction and clean-up were based on a modified QuEChERS method. The method was validated using an in-house validation based on performance characteristics modified from Commission Decision 2002/657/EC. Both matrix effect and uncertainties associated with sample preparation and instrumental analysis were minimised by the use of matrix-matched calibrations. Recoveries of analytes were generally satisfactory and typically fell between 80% and 113%. The repeatability and intermediate reproducibility measured as relative standard deviations were in most cases less than 15% (n = 63). The decision limit (CCα) and detection capability (CCß) ranged from 110.7 to 125.8 and 121.5 to 151.7 µg kg-1 for tetracyclines, 113.4 to 118.3 and 116.8 to 126.5 µg kg-1 for sulfonamides and 50.8 to 52.4 and 51.5 to 55.6 µg kg-1 for polyether ionophores, respectively. The method displayed its fitness for purpose through satisfactory results obtained in international proficiency testing schemes. The method was applied to animal and aquaculture fish tissues obtained from different sources in South Africa. Polyether ionophores were predominantly detected in samples in the range 4.26-290.10 µg/kg. Oxytetracycline was found in one porcine liver sample; however, none of the targeted analytes were present above the detection limit in the aquaculture samples.


Assuntos
Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Ionóforos/análise , Carne/análise , Sulfonamidas/análise , Tetraciclinas/análise , Animais , Bovinos , Galinhas , Cromatografia Líquida de Alta Pressão , Peixes , África do Sul , Suínos , Espectrometria de Massas em Tandem
5.
Chemosphere ; 246: 125681, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31896014

RESUMO

Tetracycline (TC) as an emerging contaminant has raised serious concerns about its toxicity and removal in wastewater treatment processes. The more toxic transformation products of TC, 4-epitetracycline (ETC), anhydrotetracycline (ATC) and 4-epianhydrotetracycline (EATC) are also widely detected. This study investigated the antibacterial and bactericidal activity of TC, ETC, ATC, EATC against Shewanella sp, using Escherichia coli and Pseudomonas aeruginosa strains as quality controls. Further, batch assays were conducted to investigate the inhibition of these antibiotics on the phosphorus removal of the Shewanella strain, and removal mechanisms of TC and its transformation products (TCs). The inhibition on phosphorus removal by the Shewanella strain at 20 mg L-1 was in the order of ATC > EATC > TC > ETC. COD removal, poly-P accumulation and glycogen synthesis by the Shewanella strain were also inhibited. Biodegradation was the main removal mechanism of TC and ETC, while adsorption was the main one of ATC and EATC. This study helps to further understand the structure-activity relationship of TC.


Assuntos
Antibacterianos/toxicidade , Fósforo/metabolismo , Shewanella/efeitos dos fármacos , Tetraciclina/toxicidade , Adsorção , Compostos Heterocíclicos , Shewanella/metabolismo , Tetraciclina/análise , Tetraciclinas/análise , Águas Residuárias
6.
J Hazard Mater ; 382: 121018, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446354

RESUMO

The broad spectrum detection of veterinary drugs is very important for rapid and large-scale safe screen of animal-derived foods. Metal-organic frameworks (MOFs), as a kind of emerged functional porous materials are quite promising in the chemical sensing and molecular detection. In this work, we report the high-performance broad spectrum detection of 15 commonly-used veterinary drugs through the fluorescence quenching in a newly-designed chemically stable Al-based MOF, Al3(µ3-O)(OH)(H2O)2(PPTTA)3/2 (BUT-22). To the best of our knowledge, this is the first systematic investigation for the application of MOFs in the detection/sensing of veterinary drugs through fluorescence quenching method. The quenching efficiencies of the tested veterinary drugs on BUT-22 are all beyond 82%, and the limits of detection (LOD) are low at parts per billion (ppb) levels. Interestingly, BUT-22 also enables the selective detection of nicarbazin (NIC) through the clearly-observed red shift of its maximum fluorescence emission wavelength. Moreover, the fluorescence quenching mechanism was explored with the help of theoretical calculations. Our work indicates that MOFs are favorable materials for the detection of veterinary drugs, being potentially useful in monitoring drug residues of animal-derived foods.


Assuntos
Alumínio/química , Estruturas Metalorgânicas/química , Drogas Veterinárias/análise , Adsorção , Ração Animal , Anti-Infecciosos/análise , Anti-Infecciosos/química , Cloranfenicol/análise , Cloranfenicol/química , Fluorescência , Inocuidade dos Alimentos , Limite de Detecção , Nitrofuranos/análise , Nitrofuranos/química , Porosidade , Sulfonamidas/análise , Sulfonamidas/química , Tetraciclinas/análise , Tetraciclinas/química , Drogas Veterinárias/química
7.
Environ Pollut ; 256: 113394, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662246

RESUMO

Tetracyclines (TCs) are frequently detected in agricultural soils worldwide, causing a potential threat to crops and human health. In this study, diffusive gradients in thin films technique (DGT) was used to measure the distribution and exchange rates of three TCs (tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC)) between the solid phase and solution in five farmland soils. The relationship between the accumulated masses with time suggested that TCs consumption in soil solution by DGT would induce the supply from the soil solid phase. The distribution coefficient for the labile antibiotics (Kdl), response time (Tc) and desorption/adsorption rates (kb and kf) between dissolved and sorbed TCs were derived from the dynamic model of DIFS (DGT induced fluxes in soils). The Kdl showed similar sizes of labile solid phase pools for TC and OTC while larger pool sizes were observed for CTC in the soils. Although the concentrations of CTC were lowest in soil solution, the potential hazard caused by continuous release from soil particles could not be ignored. The long response time (>30 min in most cases) suggested that the resupply of TCs from soil solids was limited by their desorption rates (1.26-121 × 10-6 s-1). The soils in finer texture, with higher clay and silt contents (<50 µm) showed a greater potential for TCs release.


Assuntos
Modelos Químicos , Poluentes do Solo/química , Tetraciclinas/química , Adsorção , Antibacterianos , Clortetraciclina , Difusão , Cinética , Oxitetraciclina , Solo , Poluentes do Solo/análise , Tetraciclina , Tetraciclinas/análise
8.
Talanta ; 208: 120342, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816712

RESUMO

Tetracycline antibiotics (TCs) are one kind of broad spectrum bacteriostatic agents. However, excessive use of TCs will have a threat to the environment and human health. Therefore, it is necessary to develop a simple method for direct detection of TCs. Based on intrinsic peroxidase-like activity of gold nanoclusters (AuNCs), we used TC-specific aptamers (Apt) to improve the catalytic activity of AuNCs toward the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) oxidation by H2O2, and established a colorimetric sensing platform for TCs. The catalytic enhancement by Apt allows for sensitive colorimetric detection of TCs, and Apt as molecular recognition elements can specifically combine with TCs leading to high selectivity. This developed sensing platform can quantitatively detect TCs in the concentration range of 1-16 µM with a limit of detection (LOD) as low as 46 nM. Interestingly, the naked-eye detection capability of this method is estimated to be 0.5 µM. Finally, the detection of TCs in real samples like drugs and milk was validated.


Assuntos
Aptâmeros de Nucleotídeos/química , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas/química , Leite/química , Peroxidases/metabolismo , Tetraciclinas/análise , Animais , Antibacterianos/análise , Humanos
9.
J Environ Sci Health B ; 55(3): 193-209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31658861

RESUMO

The occurrence and distribution in the aquatic environment of Nanjing of 49 antibiotics from seven therapeutic classes were investigated using an improved analytical method developed for multiclass target analysis. The results showed that these antibiotics are widely present in the water bodies of this city, with a total concentration of up to 1.958 µg L-1. The most abundant class was tetracyclines, contributing 43.7% to the total antibiotic burden. Lincomycin was detected in all samples, and the detection rate of clindamycin was 90.5%. An exploratory analysis of the data points was performed by unsupervised pattern recognition (hierarchical cluster analysis, HCA) in an attempt to clarify the pollution level in different sampling areas, and robust cluster solutions grouped the data according to their different antibiotic contaminant profiles. The safety of drinking water resources was emphasized, and the rivers, as the main receiving water body for treated and untreated wastewater in this city, were more seriously contaminated than the surrounding lakes and reservoir, not only in concentration but also in detection frequency, in our study as well as in similar research studies. A correlation analysis between the presence of antibiotics and the environmental factors was conducted, and it was found that antibiotic contamination and water quality were closely connected; the better the water quality, the lower the antibiotic contamination. Positive correlations existed between the antibiotics and tested heavy metals, as well as between antibiotics and boron and arsenic. However, whether these correlations resulted from their reaction or a common source was difficult to determine, and the mechanism requires further exploration.


Assuntos
Antibacterianos/análise , Água Potável , Poluentes Químicos da Água/análise , China , Cidades , Monitoramento Ambiental , Inocuidade dos Alimentos , Lagos/análise , Rios/química , Tetraciclinas/análise , Qualidade da Água
10.
Mater Sci Eng C Mater Biol Appl ; 105: 110132, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546396

RESUMO

In this work, nitrogen and sulfur dual-doped carbon quantum dots (N,S-CDs) from naturally renewable biomaterial fungus fibers were prepared by a biosynthesis and hydrothermal method. The N,S-CDs displayed good water solubility, excellent stability, high quantum yield (QY = 28.11%) as well as remarkable features for fluorescence quenching-based detection and cellular imaging of cancer cells. It was worth mentioning that the heteroatoms doped carbon quantum dots made from the fungus fibers had a satisfactory QY and could be used as a selective, efficient, and sensitive fluorescent probe to determine tetracyclines by the synergistic effects of static quenching and internal filtration effect. The probe demonstrated a wide linear range and low detection limit. For tetracycline, the linear range was 0.5 µM to 47.6 µM, and the corresponding detection limit was 15.6 nM. Significantly, the test papers prepared by using N,S-CDs could detect tetracyclines in aquiculture wastewater rapidly. The produced N,S-CDs did not affect the cell viability and showed great promises for cellular imaging.


Assuntos
Carbono/química , Fungos/química , Imageamento Tridimensional , Neoplasias/diagnóstico por imagem , Nitrogênio/química , Pontos Quânticos/química , Enxofre/química , Tetraciclinas/análise , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias/patologia , Tamanho da Partícula , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Tetraciclinas/farmacologia , Águas Residuárias/química
11.
J Dairy Sci ; 102(12): 10825-10837, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521351

RESUMO

In this study, we developed a microbiological inhibition method for the rapid screening of antibiotics in milk with Geobacillus stearothermophilus ATCC12980 as an indicator bacterium and an easy sample pretreatment. We observed that the limits of detection of the kit for 34 common antibiotic residues in milk, including ß-lactams (13), aminoglycosides (6), tetracyclines (4), sulfonamides (6), macrolides (4), lincosamides (1), were lower than or close to the maximum residue limits formulated by the European Union and China. Moreover, the false-positive rate was 1% and the false-negative rates were less than 5%. The ruggedness of the method (the reproducibility of detection capability of different batches of medium) met requirements at determined levels and residual limits. The shelf life of the kit was more than 6 mo at 4°C. Additionally, we observed good correlations between the kit results and ultra-high-performance liquid chromatography-tandem mass spectrometry results for incurred milk (samples taken from animals treated with antibiotics according to the pre-slaughter medication data), which indicated that the kit was reliable for screening antibiotics in incurred samples. In conclusion, the kit has a broad application potential with high sensitivity, specificity, and reproducibility, stability, and reliability, combined with simple operation, low cost, and high-throughput capacity.


Assuntos
Antibacterianos/análise , Contaminação de Alimentos/análise , Geobacillus stearothermophilus/efeitos dos fármacos , Leite/química , Aminoglicosídeos/análise , Animais , Bovinos , Cromatografia Líquida/métodos , Resíduos de Drogas/análise , Macrolídeos/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tetraciclinas/análise
12.
Nanoscale ; 11(34): 16036-16042, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31432067

RESUMO

Currently, the synthesis and applications of room-temperature phosphorescent (RTP) materials are promising, but challenging. Herein, a kind of ultra-long phosphorescent carbon dots (P-CDs) were rapidly prepared through a facile microwave-directed method. In particular, the yellow-green phosphorescence of the P-CDs was observed for up to 9 s, and their fluorescence and phosphorescence were observed at 418 nm and 525 nm, respectively, using the same excitation at 354 nm. Moreover, the RTP intensity of the P-CDs gradually decreased with the increasing pH because of the protonation-dissociated hydrogen bonds and disturbed phosphorescence sources, whereas their fluorescence exhibited general stability over a wide pH range of 2.1-12.68. Significantly, we found that both the fluorescence and the phosphorescence of the P-CDs were quenched by the introduction of tetracyclines (TCs). Specifically, the P-CDs described herein have abundant -COOH and -OH groups on their surfaces, which facilitate the linkage of CDs with TCs, thus resulting in the occurrence of an inner filter effect process (IFE). Moreover, the P-CDs showed potential as an ideal candidate for building up dual-channel assays towards the targets.


Assuntos
Carbono/química , Pontos Quânticos/química , Tetraciclinas/análise , Fluorescência , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência
13.
Sci Total Environ ; 692: 511-518, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31351293

RESUMO

Tetracycline (TC) antibiotics are widely used in livestock and poultry breeding. However, limited work has been done on the partition of TCs between suspended sediment (SPS) and overlying water or on the seasonal effects of rainfall events on the behavior of TCs in receiving rivers. Here, we assessed the impacts of rainfall events in different seasons on the concentrations and fate of TCs in a typical watershed. Concentrations of TCs in river water, SPS, and surface sediment were determined before, during, and after rainfall events. Results indicated that the sequence of TC concentration levels in river water was wet season > normal season > dry season. Rainfall events in all seasons increased the concentrations of TCs in river water. The concentration of TCs in SPS reached 104 ng/g. The SPS concentrations were only 22-78 mg/L, while the daily fluxes of TCs in particulate form contributed 39%-62% of the total (dissolved and particulate) daily fluxes in river water. The increases in TCs in river water were mainly attributed to internal release from sediment during rainfall events in the dry season but to external input during rainfall events in the wet season. The degradation products of TCs with higher concentrations and greater toxicity than their parent compounds should be considered in the ecological risk assessment of TCs. This research demonstrated that manure application should not be conducted in the normal season or before rainfall events, especially heavy rainfall.


Assuntos
Monitoramento Ambiental , Chuva , Tetraciclinas/análise , Poluentes Químicos da Água/análise , Antibacterianos/análise , China , Rios , Estações do Ano
14.
Talanta ; 204: 491-498, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357324

RESUMO

A silicon nanodots (SiNDs)-based ratiometric fluorescent sensor was designed to establish highly sensitive and selective method for detection of tetracyclines (TCs). The sensor comprises the blue fluorescence SiNDs were prepared by hydrothermal method synthesis from (3-aminopropyl)triethoxysilane and low-cost diethylenetriaminepentaacetic acid as the precursor, which serve as co-ligands for covalently bond with europium ions (Eu3+), and also the internal reference signal. In the presence of TCs, the luminescence intensity of Eu3+ was significantly increased, while the luminescence intensity of SiNDs was reduced. The fluorescence intensity ratio of I616/I450 of the sensor exhibits a sensitive linear range from 0.2 to 20 µM with a detection limit of 3 nM for the detection of TCs. This method was successfully applied to determine the levels of TCs in nature river samples and milk samples with good recoveries ranges from 92.2% to 107.4% and relative standard deviations (RSD, n = 3) was below 5%, providing a promising application future in real samples.


Assuntos
Antibacterianos/análise , Európio/química , Pontos Quânticos/química , Silício/química , Espectrometria de Fluorescência/métodos , Tetraciclinas/análise , Animais , Fluorescência , Contaminação de Alimentos/análise , Limite de Detecção , Leite/química , Rios/química , Poluentes Químicos da Água/análise
15.
Anal Bioanal Chem ; 411(23): 5963-5973, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300859

RESUMO

A microscale highly fluorescent Eu metal-organic framework (Eu-MOF) was synthesized with terephthalic acid and 1H-1,2,4-triazole-3,5-diamine by one-pot hydrothermal method. And it was characterized by scanning electron microscope, Fourier transform infrared spectroscopy, powder X-ray diffraction, fluorescence spectroscopy, thermogravimetric analysis, and energy dispersive X-ray mapping. The prepared Eu-MOF has high quantum yield of 30.99%, excellent water dispersibility, good fluorescence stability, and favorable thermal stability. Based on the distinctly different fluorescence responses of different emission, the prepared Eu-MOF was used as dual-mode visual sensor for the sensitive detection of berberine hydrochloride and tetracycline. The limits of detection are 78 nM and 17 nM, respectively. The sensing mechanism was also discussed. Moreover, a filter paper sensor has been designed for sensing tetracycline with a notable fluorescence color change from blue to red. The prepared Eu-MOF is promising to be developed as a multi-mode luminescent sensor for visual detection in biochemical analysis. Graphical abstract Illustration of the synthesis of Eu-MOF and its sensing applications for berberine hydrochloride and tetracycline.


Assuntos
Antibacterianos/análise , Berberina/análise , Európio/química , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Tetraciclinas/análise , Poluentes Químicos da Água/análise , Antibacterianos/sangue , Antibacterianos/urina , Berberina/sangue , Berberina/urina , Humanos , Limite de Detecção , Rios/química , Espectrometria de Fluorescência/métodos , Comprimidos , Tetraciclinas/sangue , Tetraciclinas/urina , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/urina
16.
Environ Pollut ; 252(Pt B): 1532-1538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31277022

RESUMO

The potential persistence and migration of 14 antibiotics comprising sulfonamides, fluoroquinolones, macrolides and tetracyclines were conducted using a 50-d recirculating flume study supported by batch attenuation experiments with spiked concentrations. The study demonstrated that photodegradation was the dominant attenuation process for these antibiotics in the water environment. The half-lives of 2-26 d were in order of sulfadiazine > sulfadimethoxine > sulfamerazine > sulfamethoxazole > sulfamethazine > sulfathiazole > ofloxacin > enrofloxacin > norfloxacin > ciprofloxacin > erythromycin > tetracycline > roxithromycin > oxytetracycline. These modest half-lives meant that the antibiotics were predicted to travel 30-400 km down a typical river before half the concentration would be lost. All antibiotics were detected on the surface sediment in the flume study. Under hyporheic exchange, some of them continually migrated into the deeper sediment and also the sediment pore water. All fluoroquinolones were detected in the sediments. The sulfonamides were detected in the pore water with relatively high concentrations and frequencies. Sulfadiazine, sulfamethazine and sulfathiazole in the upper layer pore water were found to be approaching equilibrium with the surface water. The high presence of sulfonamides in the pore water indicated that their high mobility and persistence potentially pose a risk to hyporheic zone.


Assuntos
Antibacterianos/análise , Monitoramento Ambiental/métodos , Modelos Teóricos , Rios/química , Poluentes Químicos da Água/análise , Fluoroquinolonas/análise , Hidrodinâmica , Macrolídeos/análise , Fotólise , Sulfonamidas/análise , Tetraciclinas/análise
17.
Anal Bioanal Chem ; 411(23): 6129-6139, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31278554

RESUMO

Antibiotics may be present in agricultural soils through the application of organic amendments as fertilizers or by irrigation of fields with recycled water. As a result of these agricultural practices, antibiotics in soil can lead to their uptake by plants, entering in this way the food chain. Studies on the levels of antibiotics in cereal samples are scarce in the available literature. In this work, an analytical method was developed for the determination of 19 antibiotics (fluoroquinolones, sulfonamides, tetracyclines, and lincosamides) in four types of cereal grains (wheat, barley, rice, and oat). Ultrasound-assisted matrix solid-phase dispersion was selected as extraction technique with recoveries of target analytes ranging from 73 to 127% for the four cereals analyzed. Limits of quantification obtained ranged from 0.8 to 5.8 ng g-1. Compared with methods described for the analysis of antibiotics in cereals, the developed method uses a lower volume of extraction solvent and very good recoveries were obtained for all compounds. The validated method was applied to the analysis of different types of cereals samples, harvested from agricultural fields or purchased from local supermarkets. The analysis of the five cereal samples grown in fields with 3 years of consecutive organic amendments revealed that none of the nineteen antibiotics selected were found in any sample. Eleven commercial samples of cereals of different types and presentations were analyzed and enrofloxacin was detected in one rice sample; the presence of enrofloxacin in cereals or its incorporation into crops from soil or water not previously reported. Graphical abstract.


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Grão Comestível/química , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Fluoroquinolonas/análise , Limite de Detecção , Lincosamidas/análise , Extração em Fase Sólida/métodos , Sulfonamidas/análise , Tetraciclinas/análise
18.
Food Chem ; 297: 124969, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253282

RESUMO

The wide use of tetracyclines (TCs) for prevention and therapy of animal diseases may result in excessive residues in animal products, which could pose serious risks to human health. A novel molybdenum disulfide nanoplates (MoS2 NPs)-based fluorescent sensor for tetracycline (TET) is reported. The MoS2 NPs, synthesized via a facile bottom-up hydrothermal route, showed blue fluorescence at 430 nm in aqueous solution. Interestingly, its fluorescence was quenched significantly upon addition of TET, which is mainly due to a combination of the inner filter effect and electron transfer. Thus, the MoS2 NPs based fluorescence sensor was delineated for the detection of TET. The methodology here presented showed a low detection limit of 0.032 µM and satisfied recoveries from 88.46% to 108.62% in spiked milk, milk powder and bovine muscle samples.


Assuntos
Dissulfetos/química , Contaminação de Alimentos/análise , Leite/química , Molibdênio/química , Nanoestruturas/química , Tetraciclinas/análise , Animais , Antibacterianos/análise , Bovinos , Fluorescência , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Limite de Detecção , Músculo Esquelético/química , Carne Vermelha/análise , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
19.
Artigo em Inglês | MEDLINE | ID: mdl-31176266

RESUMO

The development and validation of a throughput method for the determination of 25 antibacterial drugs (two ß-lactams, eight quinolones, two macrolides, five sulfonamides, trimethoprim, four tetracyclines and three amphenicols) in pangasius fish muscle by LC-MS/MS were performed. A simple, efficient and fast extraction procedure was developed using acetonitrile and a 0.1 M EDTA solution as solvents for extraction. All compounds were determined in a single run, and chromatographic separation was achieved using a Zorbax SB C18 column with a mobile phase comprised of purified water +0.1% formic acid (A) and acetonitrile +0.1% formic acid (B) in a linear gradient program. The method was validated aαording to the requirements of European Decision 2002/657/EC. To quantify the analytes, matrix-matched analytical curves were constructed with spiked blank tissues and showed linearity (r2) higher than 0.99. For all analytes, the precision and accuracy were determined at the levels of 3 ng/g (low), 10 ng/g (low-middle), 50 ng/g (high-middle) and 100 ng/g (high). The precision (CV%) was lower than 18.6% and the accuracy (determined as recovery) was between 65% and 119%. The limit of quantitation was 3.0 ng/g, with the exception of chloramphenicol, which was 0.3 ng/g, and amoxicillin and doxycycline, which were 10 ng/g. The method was successfully applied to analyze pangasius muscle samples from Vietnam available at the Brazilian retail market, and 5 out of 40 samples showed the presence of low-residue levels of enrofloxacin and, consequently, must be considered out of conformity. It is recommended that competent authorities should avoid the commercialization of pangasius fillet contaminated with residues of this veterinary drug.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Produtos Pesqueiros/análise , Espectrometria de Massas em Tandem/métodos , Animais , Peixes-Gato , Cloranfenicol/análise , Contaminação de Alimentos/análise , Tetraciclinas/análise , Trimetoprima/análise , Vietnã
20.
Sci Total Environ ; 684: 23-30, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31150873

RESUMO

This study investigated the removal of antibiotics by sequencing-batch membrane bioreactor (SMBR) for swine wastewater treatment. Nine compounds categorized into three groups of commonly used veterinary antibiotics, namely sulfonamides, tetracyclines and fluoroquinolones, were evaluated. Results showed that both sulfonamides and tetracyclines were efficiently removed by SMBR (>90%) while a lower removal was observed for fluoroquinolones (<70%). Mass balance analysis evidenced that biodegradation/biotransformation was the main mechanism for the removal of antibiotics in SMBR operation. Moreover, sludge adsorption and membrane retention also slightly contributed to antibiotic removal. Of the three groups of antibiotics, tetracyclines and fluoroquinolones were more prone to accumulate in biosolids. It is noteworthy that antibiotics temporarily affected SMBR performance by inhibiting sludge growth and activity as well as increasing the concentrations of extracellular polymeric substances and soluble microbial products in the mixed liquor. Nevertheless, >60% of organic matter and nutrients in swine wastewater could be removed over SMBR operation.


Assuntos
Antibacterianos/análise , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Adsorção , Criação de Animais Domésticos , Animais , Fluoroquinolonas/análise , Membranas Artificiais , Sulfonamidas/análise , Suínos , Tetraciclinas/análise , Eliminação de Resíduos Líquidos/instrumentação , Qualidade da Água
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