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1.
Environ Pollut ; 355: 124198, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38782161

RESUMO

Electro-Fenton (EF) can in-situ produce H2O2 and effectively activate H2O2 to generate powerful reactive species for the destruction of contaminants under acidic conditions, however, the production of iron-containing sludge and requirement of low working pH significantly hinder its practical application. Herein, a novel Cu, N co-doped carbon (Cu-N@C) with metal organic framework (MOF) as a precursor was constructed and adopted for the elimination of pefloxacin (PEF) in the heterogeneous electro-Fenton (HEF) process. PEF could be almost completely removed within 1 h and total organic carbon (TOC) removal efficiency was 48.57% within 6 h. Meanwhile, Cu-N@C had good repeatability and environmental adaptability, it can still maintain excellent catalytic performance after 10 cycles, and it exhibited satisfactory remediation performance in simulated water matrix. In addition, the HEF process catalyzed by Cu-N@C also showed satisfactory degradation effect on other organic pollutants including atrazine, methylene blue, and chlorotetracycline. Under the action of impressed current, the HEF system could generate H2O2 in-situ, and the active species could be generated in the redox cycle of Cu0/Cu1+/Cu2+. Electron paramagnetic resonance and quenching experiments confirmed that •OH was the dominant active species in the degradation of organic compounds. The degradation process of PEF was studied by mass spectrometry analysis of intermediate products. This study provided a simple method to prepare MOF-based electrocatalyst, which exhibits promising application potential for treatment wastewater.


Assuntos
Carbono , Cobre , Peróxido de Hidrogênio , Ferro , Nanocompostos , Pefloxacina , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/química , Catálise , Cobre/química , Carbono/química , Nanocompostos/química , Pefloxacina/química , Ferro/química , Nitrogênio/química , Estruturas Metalorgânicas/química
2.
Chem Biodivers ; 20(9): e202300702, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37528701

RESUMO

Twelve new heteroleptic nickel(II) and copper(II) complexes of the type [M(L1-6 )(Pfx)2 ] (1-12), where L1-6 =2-benzylidenehydrazinecarbothioamide (L1 ), 2-benzylidene-N-methylhydrazinecarbothioamide (L2 ), 2-benzylidene-N-phenylhydrazinecarbothioamide (L3 ), 2-(4-methylbenzylidene)hydrazinecarbothioamide (L4 ), 2-(4-methylbenzylidene)-N-methylhydrazinecarbothioamide (L5 ) and 2-(4-methylbenzylidene)-N-phenylhydrazinecarbothioamide (L6 ), Pfx=pefloxacin and M=Ni(II) or Cu(II) have been synthesised, and their structures were confirmed by different spectral techniques. The spectral data and density functional theory (DFT) calculations supported the bonding of pefloxacin drug molecule via one of the carboxylate oxygen atoms and the pyridone oxygen atom, and the thiosemicarbazone ligand via the imine nitrogen and the thione sulfur atoms with the metal(II) ion, forming distorted octahedral geometry. In vitro antiproliferative activity of the synthesized complexes was evaluated against three human breast cancer (T47D, estrogen negative (MDA-MB-231) and estrogen positive (MCF-7)) as well as non-tumorigenic human breast epithelial (MCF-10a) cell lines, which showed the higher activity for the copper(II) complexes. The interaction of the synthesized complexes with an oncogenic protein H-ras (121 p) was explored by in silico molecular docking studies. Further, in silico pharmacokinetics and ADMET parameters were also analysed to predict the drug-likeness as well as non-toxic and non-carcinogenic behavior, and safe oral administration of the complexes.


Assuntos
Complexos de Coordenação , Tiossemicarbazonas , Humanos , Cobre/química , Níquel/química , Simulação de Acoplamento Molecular , Pefloxacina , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Ligantes , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Estrogênios , Oxigênio
3.
Talanta ; 255: 124216, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36587425

RESUMO

The current effort introduces a facile construction of peony-like CuO:Tb3+ nanostructure (P-L CuO:Tb3+ NS), whose characterization was determined via techniques of X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. We investigated ofloxacin, pefloxacin and gatifloxacin oxidation electrochemically on P-L CuO:Tb3+ NS-modified glassy carbon electrode (P-L CuO:Tb3+ NS/GCE), the results of which revealed the irreversible oxidation of drugs through a two-electron oxidation process. An admirable resolution was found for this modified electrode between voltammetric peaks of ofloxacin, pefloxacin and gatifloxacin, suggesting its appropriateness for simultaneous detection of these drugs in pharmaceutical media. In addition, our nanostructure synergistically influenced the electro-catalytic oxidations of these three compounds. Differential pulse voltammetric measurements of ofloxacin, pefloxacin and gatifloxacin through our sensor showed a limit of detection of 1.9, 2.3 and 1.2 nM a as well as a linear dynamic range between 0.01 and 800.0 µM in phosphate buffered solution (0.1 M, pH = 6.0), respectively. Moreover, as-fabricated sensor could successfully co-detect these drugs in real serum and tablets specimens. In addition, since we use animal foods such as milk it is very important to detect their fluoroquinolone residues. For this purpose, the proposed sensor was tested to determine the residues of ofloxacin, pefloxacin and gatifloxacin in milk.


Assuntos
Ofloxacino , Pefloxacina , Ofloxacino/química , Gatifloxacina , Cobre/química , Térbio , Óxidos/química , Eletrodos , Técnicas Eletroquímicas/métodos
4.
Analyst ; 148(2): 381-390, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36537261

RESUMO

The synthetic antibiotics fluoroquinolones are popular due to their good antibacterial performance and low price, but the risk to human health caused by their residues has attracted great attention. In this study, an ultra-sensitive mAb, 4D7, was prepared with an IC50 of 0.027 ng mL-1 to norfloxacin (NOR) and cross-reactivity of 19.7-47.7% to lomefloxacin (LOM), pefloxacin (PEF), ofloxacin (OFL), enrofloxacin (ENR), ciprofloxacin (CIP), and danofloxacin (DAN). Based on mAb 4D7 and Eu-fluorescent microspheres, a rapid and sensitive immunochromatographic strip was developed for the detection of fluoroquinolone residues in fish and milk. The detection ranges (IC20-IC80) of the strip for the detection of NOR, PEF, LOM, OFL, ENR, CIP and DAN were 0.19-1.1 µg kg-1, 0.39-2.1 µg kg-1, 0.5-2.6 µg kg-1, 0.43-3.3 µg kg-1, 0.61-3.5 µg kg-1, 0.69-5.5 µg kg-1, 0.52-3.4 µg kg-1 in fish, and 0.027-0.19 µg kg-1, 0.049-0.34 µg kg-1, 0.069-0.39 µg kg-1, 0.06-0.41 µg kg-1, 0.089-0.65 µg kg-1, 0.12-0.81 µg kg-1, 0.091-0.52 µg kg-1 in milk, respectively. The recovery rates in spiked sample tests were 88.6-113.6% with a coefficient of variation less than 8.4%. Thus the newly-developed strip was sensitive and reliable for rapid on-site detection of fluoroquinolone residues in fish and milk.


Assuntos
Fluoroquinolonas , Leite , Animais , Humanos , Leite/química , Fluoroquinolonas/análise , Antibacterianos/análise , Pefloxacina/análise , Ciprofloxacina/análise , Norfloxacino , Ofloxacino
5.
Anal Chim Acta ; 1235: 340539, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36368827

RESUMO

The environmental pollution and human health risks caused by anti-infective residual drugs in the environment have attracted much attention. More convenient and effective detection methods to achieve the rapid and high sensitivity detection for such pollutants are required. In this work, a novel surface-enhanced Raman scattering (SERS) strategy based on vortex aggregation of AgNPs was proposed for the detection of anti-infective drugs in environmental water. The method enhanced the Raman signal of the targets by 2-7.4 times. The mechanism of aggregation enhancement effect under the low-frequency oscillation procedure which significantly enhanced the SERS signal of targets molecular on the aggregated AgNPs was revealed by UV-vis and ICP-MS methods. Three drugs of cefazolin sodium, pefloxacin, and chloroquine phosphate were determined. The detect limits were 3.97 × 10-9 mol/L, 2.42 × 10-10 mol/L, and 7.34 × 10-9 mol/L for cefazolin sodium, pefloxacin, and chloroquine phosphate, respectively. The quantitative relationships were obtained in a wide linear range of 4-5 orders as well as good accuracy and stability with the recoveries of 84.0%-97.1% and the relative standard deviations (RSDs) less than 4.6% for spiked in actual water samples. This method also had excellent repeatability and stability, which have potential application for rapid detection of trace pollutants in water environment.


Assuntos
Anti-Infecciosos , Resíduos de Drogas , Poluentes Ambientais , Nanopartículas Metálicas , Humanos , Prata/química , Nanopartículas Metálicas/química , Água , Pefloxacina , Cefazolina , Análise Espectral Raman/métodos
6.
Water Res ; 225: 119138, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191526

RESUMO

Intensive use of antibiotics affects biogeochemical cycles and stimulates the evolution of antibiotic resistance, thus threatening global health and social development. The spatiotemporal distributions of antibiotics in single aqueous matrices have been widely documented; however, their occurrence in surface-groundwater systems has received less attention, especially in arid regions that usually have fragile ecosystems. Therefore, we investigated the occurrence of thirty-one antibiotics in the surface water and adjacent groundwater in the Xinjiang Uygur Autonomous Region, China. The results showed that the total concentrations of detected antibiotics varied from 17.37 to 84.09 ng L-1 and from 16.38 to 277.41 ng L-1 in surface and groundwater, respectively. The median concentration of antibiotics showed the pattern of norfloxacin (4.86 ng L-1) > ciprofloxacin (3.93 ng L-1) > pefloxacin (3.39 ng L-1) in surface water; whereas in groundwater, this was in the order of pefloxacin (6.30 ng L-1) > norfloxacin (4.33 ng L-1) > ciprofloxacin (2.68 ng L-1). Heatmap analysis indicated that vertical infiltration had limited effects on antibiotic exchange in surface-ground water systems because of the high potential evaporation and low water storage. Redundancy analysis suggested that the oxidation-reduction potential (p < 0.01) and dissolved oxygen (p < 0.05) jointly affected the distribution of antibiotics in surface water. Ecological risk assessment showed that antibiotics in 98.9% of surface water and 99.1% of groundwater did not pose significant risks to aquatic species. The findings of this study will help develop effective mitigation strategies for antibiotics in aquatic environments.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Antibacterianos/análise , Norfloxacino , Monitoramento Ambiental , Ecossistema , Poluentes Químicos da Água/análise , Pefloxacina/análise , Ciprofloxacina/análise , Medição de Risco , Água/análise , Oxigênio/análise , China
7.
Se Pu ; 40(9): 843-853, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36156631

RESUMO

Chromatography combined with mass spectrometry is the most commonly used detection technology, and it offers the advantages of high sensitivity and high selectivity. The quick, easy, inexpensive, effective, rugged, and safe (QuEChERS) method is low-cost, effective, and time efficient. The application of the QuEChERS has now been extended to the analysis of contaminants in food samples. The aim of the study was to identify different concentration levels of multiple harmful drug residues in bean sprouts. In this study, QuEChERS coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the simultaneous determination of 40 plant growth regulators, fungicides, insecticides, and antibiotics in bean sprouts. In the HPLC-MS/MS experiment, gibberellic acid, 4-fluorophenoxyacetic acid, chloramphenicol, N6-(δ2-isopentenyl)-adenine, 6-benzylaminopurine, 4-chlorophenoxyacetic acid, and 2,4-dichlorophenoxyacetic acid (2,4-D) were analyzed by MS/MS with negative electrospray ionization (ESI-). The other 33 target analytes (chlormequat, ronidazole, metronidazole, pymetrozine, dimetridazole, methomyl, carbendazim, enoxacin, levofloxacin, pefloxacin mesylate, norfloxacin, ciprofloxacin, enrofloxacin, thiabendazole, lomefloxacin, chlorpyrifos, sarafloxacin, imidacloprid, etc.) were analyzed by MS/MS with positive electrospray ionization (ESI+). Sensitive MS conditions were realized by optimizing the instrumental parameters such as the desolvent temperature, collision energy, spraying needle position, precursor ions, and product ions. Then, the optimal pretreatment method was determined by comparing the recovery rates of the 40 drugs obtained with different extraction solvents (methanol, acetonitrile, acetonitrile containing 0.1% ammonia, acetonitrile with 1% acetic acid), different extraction methods (ultrasonic extraction, shaking extraction), and purification with primary secondary amine (PSA) and C18. In this study, the bean sprouts samples were extracted twice by 10 mL acetonitrile with 1% acetic acid, and extracted under ultrasonic conditions. Then, the extracting solution was only cleaned with 100 mg C18. The chromatographic separation of the 40 compounds was accomplished on a Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm) with gradient elution. Methanol and 0.01% formic acid aqueous solution were used as the mobile phases. The 40 compounds were analyzed in the multiple reaction monitoring (MRM) mode. The matrix matching external standard method was used for quantitative determination. The results showed that the 40 compounds could be analyzed within 15 min. Under the optimized conditions, the calibration curves showed good linearities for the 40 compounds, and the coefficients of determination (r2) were greater than 0.99 in the range of 2-200 µg/L. The limits of detection (LODs) and limits of quantification (LOQs) were in the range of 0.1-3 µg/kg and 0.3-9 µg/kg, respectively. Using negative bean sprouts as the substrates, the recovery tests were carried out at three spiked levels of 5, 10, and 50 µg/kg. The average recoveries of the 40 drugs were 78.5% to 115.3%, and the corresponding relative standard deviations (RSDs) were 1.3% to 9.7% (n=6). This method was successfully applied to the analysis of the 40 drug residues in 21 batches of local bean sprouts in Handan city. The results revealed the presence of extensive drug residues in the bean sprouts. The 26 batches were detected to varying degrees, among which 4-chlorophenoxyacetic acid, carbendazim, 6-benzyladenine, 2,4-D, enrofloxacin, and metronidazole were detected at high rates. The detection rates of 4-chlorophenoxyacetic acid, 6-benzyladenine, carbendazim, 2,4-D, gibberellic acid, and enrofloxacin were 28.6%, 19.0%, 9.5%, 9.5%, 4.8%, and 4.8%, respectively. The contents ranged from 37.5-352.4, 32.4-273.1, 28.8-38.7, 316.1-20.2, 19.9 and 13.6 µg/kg, respectively. Given its advantages of simplicity, rapidness, and high sensitivity, the developed method can be used for the rapid and accurate determination of trace levels of the 40 drug residues in large quantities of bean sprouts.


Assuntos
Clorpirifos , Fungicidas Industriais , Inseticidas , Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Ácido 2,4-Diclorofenoxiacético/análise , Acetonitrilas , Adenina , Amônia , Antibacterianos , Benzimidazóis , Compostos de Benzil , Carbamatos , Cloranfenicol/análise , Clormequat , Cromatografia Líquida de Alta Pressão , Ciprofloxacina , Dimetridazol , Enoxacino , Enrofloxacina , Fungicidas Industriais/análise , Giberelinas , Inseticidas/análise , Levofloxacino , Metanol , Metomil , Metronidazol , Norfloxacino , Pefloxacina , Reguladores de Crescimento de Plantas/análise , Purinas , Ronidazole , Solventes , Espectrometria de Massas em Tandem , Tiabendazol
8.
Environ Res ; 215(Pt 1): 114135, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35998699

RESUMO

For investigating the spatial, temporal variations and assessing ecological risk of 10 antibiotics and 6 antimycotics, influent sewage water and treated effluent were collected during three different seasons in 19 waste water treatment plants of Tianjin. High performance liquid chromatography tandem mass spectrometry was used to analyze 16 substances. The concentration range of influent samples was not detected (nd) -547.94 ng/L and the concentration range of effluent samples was nd-52.97 ng/L. By calculating the removal efficiency, it was found that Ciprofloxacin (CIP), Ofloxacin (OFL) and Clotrimazole (CTR) were effectively removed. There were significant spatial and temporal differences, the concentration in the dry season was evidently higher than that in the wet and normal seasons, and the northeast was lower than that in the northwest and southeast. By establishing a data set of influent and effluent, the priority features were extracted by feature engineering, which were temperature and NH3-N. Under the condition of ensuring the best performance of the models, the influent model with 9 features and the effluent model with 4 features were established, and the quantitative relationship between the above features and concentration was obtained through partial dependence analysis. Except for Moxifloxacin (MOX), Norfloxacin (NOR) and OFL in the influent samples, the RQ values for other antibiotics and antimycotics were less than 0.1. Among the effluent samples, only NOR had an RQ value greater than 0.1, and OFL, MOX, and Pefloxacin (PEF) had RQ values between 0.01 and 0.1. Comparing the observations and predictions individual RQ values, the predictions were ideal and matched the observations. This work effectively assessed environmental impact and provided a valuable reference for evaluating antibiotics and antimycotics ecological toxicity.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Antibacterianos/análise , Ciprofloxacina , Clotrimazol/análise , Monitoramento Ambiental , Moxifloxacina/análise , Norfloxacino , Ofloxacino/análise , Pefloxacina/análise , Medição de Risco , Esgotos/química , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Poluentes Químicos da Água/análise
9.
Chemosphere ; 303(Pt 3): 135299, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35691401

RESUMO

The degradation of toxic chemicals, antibiotics and other residues in organic wastewater has attracted much attention. Among various degradation technologies, hydrodynamic cavitation (HC) reactors have the advantage of being simple to operate. Through the combination of HC and other oxidants, the removal efficiency and energy efficiency of organic matter can be greatly improved, and the consumption of chemicals and the processing costs can be reduced. In this work, HC technology combined with oxidants was used to degrade pefloxacin (PEF), and the effect of different operating conditions on PEF degradation was investigated. The results indicated that the removal efficiency of PEF treated with HC alone was 84.9% under the optimal HC conditions of pH 3.3 and 120 min, which is much higher than that (35.5%) of pH 5.3. When co-treating the PEF solution with HC and H2O2 at 0.3 MPa and pH 5.3, the optimal molar ratio of PEF to H2O2 was 1:5, the highest PEF removal efficiency was 69.7%, and the synergy index (SI) was 4.4. When combining HC with O3, the PEF removal efficiency gradually elevated with increasing ozone addition. When the addition amount of ozone was 0.675 g/h, the removal efficiency of PEF was the highest, which was 91.5% after treatment of 20 min. The intermediate products in the reaction process were analyzed based on UV-Vis spectroscopy and LC-MS, and the mechanism and reaction pathways of PEF were proposed.


Assuntos
Ozônio , Poluentes Químicos da Água , Hidrodinâmica , Peróxido de Hidrogênio/química , Oxidantes , Ozônio/química , Pefloxacina , Poluentes Químicos da Água/química
10.
ACS Chem Neurosci ; 13(12): 1805-1817, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35657695

RESUMO

Quinolone antibiotics disrupt bacterial DNA synthesis by interacting with DNA gyrase and topoisomerase IV. However, in addition, they have been shown to act as inhibitors of pentameric ligand-gated ion channels such as GABAA receptors and the α7 nicotinic acetylcholine receptor (nAChR). In the present study, we have examined the effects of quinolone antibiotics on the human α4ß2 nAChR, an important subtype that is widely expressed in the central nervous system. A key feature of α4ß2 nAChRs is their ability to coassemble into two distinct stoichiometries, (α4)2(ß2)3 and (α4)3(ß2)2, which results in differing affinities for acetylcholine. The effects of nine quinolone antibiotics were examined on both stoichiometries of the α4ß2 receptor by two-electrode voltage-clamp recording. All compounds exhibited significant inhibition of α4ß2 nAChRs. However, all of the fluoroquinolone antibiotics examined (ciprofloxacin, enoxacin, enrofloxacin, difloxacin, norfloxacin, pefloxacin, and sparfloxacin) were significantly more potent inhibitors of (α4)2(ß2)3 nAChRs than of (α4)3(ß2)2 nAChRs. This stoichiometry-selective effect was most pronounced with pefloxacin, which inhibited (α4)2(ß2)3 nAChRs with an IC50 of 26.4 ± 3.4 µM but displayed no significant inhibition of (α4)3(ß2)2 nAChRs. In contrast, two nonfluorinated quinolone antibiotics (cinoxacin and oxolinic acid) exhibited no selectivity in their inhibition of the two stoichiometries of α4ß2. Computational docking studies suggest that pefloxacin interacts selectively with an allosteric transmembrane site at the ß2(+)/ß2(-) subunit interface, which is consistent with its selective inhibition of (α4)2(ß2)3. These findings concerning the antagonist effects of fluoroquinolones provide further evidence that differences in the subunit stoichiometry of heteromeric nAChRs can result in substantial differences in pharmacological properties.


Assuntos
Antibacterianos , Fluoroquinolonas , Antagonistas Nicotínicos , Pefloxacina , Receptores Nicotínicos , Antibacterianos/farmacologia , Fluoroquinolonas/farmacologia , Humanos , Antagonistas Nicotínicos/farmacologia , Oócitos , Pefloxacina/farmacologia , Receptores Nicotínicos/metabolismo
11.
Colloids Surf B Biointerfaces ; 217: 112649, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35753193

RESUMO

By integrating the fluorescence of quantum dots (QDs) and Mn2+-pefloxacin mesylate (Mn2+-pefloxacin), a new type of dual-band fluorescence biosensor for high-efficiency and sensitive determination of double-stranded DNA (dsDNA) is developed. The biosensor is based on the fluorescence "OFF-ON" mode of both QDs and QDs-Mn2+-pefloxacin. The Mn2+-pefloxacin complex can quench the QDs fluorescence via photoinduced electron transfer (PET), and its fluorescence is also quenched. Due to the specificity and strong binding affinity of dsDNA for the Mn2+-pefloxacin complex, it can break the low fluorescent QDs-Mn2+-pefloxacin and restore the fluorescence of QDs and Mn2+-pefloxacin complex in their respective bands. Therefore, the dual-band fluorescence quantitative detection of dsDNA by QDs-Mn2+-pefloxacin can be achieved, while bovine serum albumin, single-stranded DNA, and bio-related ions do not yield similar results. Furthermore, the possible reaction mechanisms are systematically discussed. The detection limits (3δ/K) of herring sperm (hs) DNA in the fluorescence recovery bands of QDs and Mn2+-pefloxacin complex are 0.0142 and 0.0465 µg/mL, respectively. The developed biosensor was used for dsDNA detection in synthetic samples, and desirable results are obtained.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Técnicas Biossensoriais/métodos , DNA , Fluorescência , Humanos , Masculino , Pefloxacina , Sêmen , Espectrometria de Fluorescência/métodos
12.
J Environ Sci Health B ; 57(7): 517-525, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35477387

RESUMO

A rapid colloidal gold immunochromatography assay (GICA) for the detection of pefloxacin (PEF) was established and optimized. The anti-PEF monoclonal antibody (mAb) was used to target PEF as a colloidal gold-mAb conjugate. The mAb belonged to the IgG2b subtype, lambda light chain, the affinity constant (Ka) was 5.21 × 109 L·mol-1, and its half maximal inhibitory concentration (IC50) was 0.23 ng·mL-1. No obvious cross-reactivity (CR) was observed with other common fluoroquinolone antibiotics, including ciprofloxacin (CIP), norfloxacin (NOR), lomefloxacin (LOM) and ofloxacin (OFL). The visual limit of detection (vLOD) of the optimized GICA was 2 ng·g-1 under the conventional pretreatment method, and the assay was completed in 15 min. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) was employed to confirm the performance of the strip. In addition, a novel pretreatment was established and compared with conventional pretreatment. Without the removal of organic solvents, the novel pretreatment method reduced the sample pretreatment time (more than 10 min). The vLOD of the optimized GICA was also 2 ng·g-1 when applying the novel pretreatment method. In conclusion, the proposed PEF-GICA could detect samples containing PEF rapidly and accurately, and the novel pretreatment method saved the time of sample pretreatment and improved the efficiency of detection.


Assuntos
Carpas , Coloide de Ouro , Animais , Cromatografia de Afinidade/métodos , Cromatografia Líquida , Coloide de Ouro/química , Pefloxacina/farmacologia , Espectrometria de Massas em Tandem
13.
Environ Sci Pollut Res Int ; 29(28): 43201-43211, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35091955

RESUMO

In this paper, one kind of acid-alkali modified sludge-based biochar (ASBC) was synthesized, characterized, and employed as adsorbent for the removal of pefloxacin. The characterization results showed that the specific surface area (SSA) of ASBC (53.381 m2/g) was significantly higher than that of SBC (24.411 m2/g). ASBC had a rougher surface, larger particle distribution, lower zero point charge, and richer functional groups (e.g., C-O and O-H) than SBC. The adsorption capacity of ASBC was 1.82 times than that of SBC. After 8 adsorption cycles in reuse experiment, the adsorption capacity of ASBC for pefloxacin still reached 144.08 mg/L, indicating that ASBC has good reusability. Static experiments showed that the optimal pH value was 6.0 in the adsorption of pefloxacin on SBC and ASBC. The result of adsorption kinetics indicated that the pseudo-second-order model could describe well the adsorption process. The Freundlich model was better than the Langmuir model to describe the adsorption of pefloxacin by ASBC, indicating that the adsorption process was mainly multilayer adsorption. Thermodynamic result showed that the adsorption of pefloxacin by ASBC was spontaneous and endothermic. The removal mechanism of pefloxacin by ASBC is mainly the substitution reaction and π-π EDA interaction. In summary, acid-alkali modified biochar is an effective adsorbent for pefloxacin in aqueous solution, and has great application prospects.


Assuntos
Esgotos , Poluentes Químicos da Água , Adsorção , Álcalis , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Cinética , Pefloxacina , Termodinâmica , Água , Poluentes Químicos da Água/análise
14.
Mol Divers ; 26(2): 869-878, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33646502

RESUMO

Pefloxacin-based mixed ligand Cu(II) complexes with substituted isatin of type [Cu(Isatin)(Pefloxacin)Cl] were synthesized, and characterized by EPR, mass, FT-IR, electronic spectrometry, metal content, magnetic moment, and conductance measurement. The g factors g [Formula: see text] > g [Formula: see text] > 2.0023 observed in EPR suggest a square-pyramidal environment of ligands around the copper metal. The compounds were screened for diverse biological activities. The compounds inhibit efficiently the cell proliferation of HCT 116 cancer cells. To take the insight of anticancer activity mechanism, we investigated compound-1 for further cellular assay-based biological activities like trypan blue assay, cell morphological alteration assay, colony formation assay, cell apoptosis, and cell necrosis assay. The compound-1 induced distinct morphological alteration in cells, inhibits cell viability, decreases % plating efficiency, and decreases the clonogenic ability of the HCT 116 cells. The cell death mechanism was confirmed by annexin V-FITC / PI assay and LDH release assay. The positive annexin V/PI stained cells in presence of compound-1 and the absence of a significant amount of lactate dehydrogenase suggest cell apoptosis mechanism for anticancer activity of compounds. We also screened compounds for in vitro antibacterial and cytotoxic activities. Synthesis, characterization, antibacterial, anticancer, and cytotoxicity activities of pefloxacin based Cu(II) complexes were studied. The compound -1 is more potent than standard anticancer drugs and it induced apoptosis to the HCT 116 cells.


Assuntos
Antineoplásicos , Isatina , Antibacterianos/química , Antineoplásicos/química , Cobre/química , Cobre/farmacologia , Fluoroquinolonas/farmacologia , Humanos , Isatina/química , Ligantes , Pefloxacina , Espectroscopia de Infravermelho com Transformada de Fourier
15.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34356003

RESUMO

Introduction. Fluoroquinolone (FQ) resistant Salmonella are classified as high priority pathogens by WHO. FQ resistance among Salmonella Typhi has emerged rapidly and is predominantly mediated by mutations in the topoisomerase genes gyrA, and parC. Mutations in GyrA result in classical FQ resistance (DCS-NAR) i.e. decreased susceptibility to ciprofloxacin (MIC of 0.12 to 0.5 µg ml-1) (DCS) and resistance to nalidixic acid (NAR). Previously a nalidixic acid disc test was proposed for detection of DCS. Recently isolates with non-classical FQ resistance caused by plasmid-mediated quinolone resistance (PMQR) and mutations in GyrB have emerged. These mechanisms also result in DCS but are nalidixic acid susceptible (NAS) and thus pose diagnostic challenges. CLSI and EUCAST have recommended use of 5 µg pefloxacin discs for detection of DCS in Salmonella.Hypothesis. The CLSI and EUCAST recommendations for use of 5 µg pefloxacin for detection of DCS has not been validated on typhoidal Salmonella and resistance mediated by GyrB mutation in Salmonella species.Aim. The aim of the present study was to validate the performance of the 5 µg pefloxacin discs to detect isolates of S. Typhi with DCS with special reference to GyrB mutations.Methodology. A total of 180 clinical isolates of Salmonella Typhi (2005-2014) were investigated for genetic mechanisms of resistance. Zone diameters for nalidixic acid (30µg), ciprofloxacin (5µg) and pefloxacin (5µg) and minimum inhibitory concentration (MIC) for ciprofloxacin were determined using CLSI guidelines. Performance of the three discs was evaluated to detect FQ resistance in S. Typhi.Results. Topoisomerase mutations in GyrB +/ ParC and GyrB were detected in 112 and 34 isolates respectively. Different mutations have a varied effect on the MIC for ciprofloxacin. The current breakpoints for susceptible (≤0.06 µg ml-1) and non-susceptible (≥0.125 µg ml-1), failed to detect all isolates with a resistance mechanism. Performance of both ciprofloxacin and pefloxacin discs were excellent compared to nalidixic acid in differentiating isolates with non-classical resistance mediated by GyrB from wild-type.Conclusion. The pefloxacin disc can be used to detect FQ resistance among S. Typhi. This is the first report of validation of pefloxacin for detection of FQ resistance in S. Typhi mediated by GyrB mutation.


Assuntos
DNA Girase/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Pefloxacina/farmacologia , Salmonella typhi/efeitos dos fármacos , Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , DNA Topoisomerase IV/genética , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Ácido Nalidíxico/farmacologia , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Inibidores da Topoisomerase II/farmacologia , Febre Tifoide/microbiologia
16.
Mater Sci Eng C Mater Biol Appl ; 118: 111439, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255032

RESUMO

The increased efflux of fluoroquinolone antibiotics to the environment has become of worldwide concern due to their potential to disturb aquatic ecosystems. How to improve the antibiotic release is a challenge. In this work, magnetic Fe3O4 nanoparticles as a drug release vehicle were prepared using the green synthesis method. It is a simple and environmental friendly technique that employs the plant extract as a reducing and coating agent during the preparation process. Antibiotics ofloxacin and pefloxacin served as the drug model and the drug release behavior was tested at various pH levels. The release efficiency of ofloxacin from Fe3O4 reached 99.6% and for pefloxacin it was 57.0% at 310 K after 120 h (pH 10.5). The scanning electron microscope images show that Fe3O4 particles ranged in size from 10 to 40 nm and magnetism testing indicated that saturation magnetization was 58.7 emu/g. Furthermore, zeta potential, FTIR, UV-VIS, XRD and XPS were used to provide the evidence to support the release mechanism, where was based on the pH control. Our work clearly demonstrated that Fe3O4 nanoparticles were a potential as a targeted drug delivery system.


Assuntos
Ofloxacino , Pefloxacina , Antibacterianos , Ecossistema , Fenômenos Magnéticos
17.
J Colloid Interface Sci ; 583: 279-287, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002699

RESUMO

While Fe-based metal-organic frameworks (MOFs) can be used to remove antibiotics by adsorption, knowledge of how antibiotics are degraded by MOFs is still limited. In this study, one Fe-based MOF, NH2-MIL-88B was used to remove pefloxacin from aqueous solution via a combination of adsorption and Fenton-like oxidation. NH2-MIL-88B exhibited a high adsorption capacity for pefloxacin (41.37 mg·g-1), with >99% removal efficiency within 120 min based on Fenton-like oxidation. To better understand the mechanisms involved in integrated adsorption and Fenton-like oxidation, various advanced characterization techniques were used to monitor the changes in morphology and composition of NH2-MIL-88B before and after removal of pefloxacin. Scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) all supported adsorption and Fenton oxidation of pefloxacin. In addition, the pefloxacin degradation products identified by LC-UV and LC-MS provided information on the potential adsorption-Fenton oxidation mechanism. These results suggested that NH2-MIL-88B has remarkably potential to be used in an integrated adsorption and Fenton-like process for the removal of antibiotics from aqueous solution.


Assuntos
Estruturas Metalorgânicas , Pefloxacina , Adsorção , Oxirredução
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 234: 118247, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32179465

RESUMO

A novel solvothermal process for synthesizing InNbO4 nanomaterials was developed. In this manner, a series of InNbO4 samples was synthesized. It was shown that reaction temperature and precursor pH had strong influence on the attributes of InNbO4 samples. The X-ray diffraction patterns revealed that all the samples possessed monoclinic structure and the optimal reaction condition was found at 250 °C with a pH of 5. Scanning electron microscopy images of different InNbO4 samples showed various morphologies. Transmission electron microscopy verified the synthesized InNbO4-pH 5 was single-crystal cubes. X-ray photoelectron spectra verified the existence of In, Nb, and O in InNbO4-pH 5 sample. The band gap of InNbO4-pH 5 was calculated to be 2.51 eV. The photocurrent intensity of InNbO4-pH 5 was the highest among the prepared samples. The photocatalytic degradation of pefloxacin was investigated using these samples. The InNbO4-pH 5 exhibited best degradation efficiency among these samples. The removal efficiency of pefloxacin with InNbO4-pH 5 could reach 80.2% in 60 min. Based on free radical capture results, superoxide radicals and holes showed to be the dominant active species. In addition, UHPLC/MS/MS was used to identify the degradation intermediates. Five new pefloxacin degradation products were found and possible degradation pathways were suggested.


Assuntos
Índio/química , Nióbio/química , Pefloxacina/química , Solventes/química , Temperatura , Catálise , Cristalização , Concentração de Íons de Hidrogênio , Nitrogênio/química , Espectroscopia Fotoeletrônica , Fotólise , Espectrofotometria Ultravioleta , Difração de Raios X
19.
J Pak Med Assoc ; 70(1): 96-99, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31954032

RESUMO

OBJECTIVE: To determine the use of pefloxacin as a surrogate marker to detect fluoroquinolone (ciprofloxacin) susceptibility against Salmonella enterica serotypes Typhi and Paratyphi A. METHODS: The prospective, descriptive cross-sectional study was conducted at the Aga Khan University Hospital, Karachi, from September 2016 to March 2018, and comprised Salmonella Typhi and Paratyphi A isolates of blood cultures. Disk susceptibility tests and broth microdilution to test minimum inhibitory concentration were performed as per standard guidelines. Data was analysed using SPSS 21. RESULTS: Of the 138 isolates, 91(66%) were intermediate resistant to ciprofloxacin but were resistant to pefloxacin, 42(30%) were resistant to both ciprofloxacin and pefloxacin, and 5(4%) were susceptible to both ciprofloxacin and pefloxacin. Of the isolates that were intermediate resistant to ciprofloxacin, 85(93%) had minimum inhibitory concentration range0.12-0.5mg\L, while 6(7%) had MIC>1mg\L (p<0.0001). CONCLUSIONS: Pefloxacin disk diffusion test was found to be reliable in detecting fluoroquinolone resistance among enteric fever causing Salmonella.


Assuntos
Ciprofloxacina/farmacologia , Testes de Sensibilidade Microbiana , Pefloxacina/farmacologia , Salmonella paratyphi A/efeitos dos fármacos , Salmonella typhi/efeitos dos fármacos , Antibacterianos/farmacologia , Estudos Transversais , Humanos , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Estudos Prospectivos , Infecções por Salmonella/microbiologia
20.
Drug Chem Toxicol ; 43(5): 496-503, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30257570

RESUMO

Pefloxacin is a second-generation fluoroquinolone antibiotic. Besides its advantageous characteristics, side effects including the hypofunction of salivary glands, decreased saliva production, and peripheral neuropathy were observed during the administration of pefloxacin. The aim of this study was to investigate the changes in the number of serotonergic immunoreactive fibers and mast cells after pefloxacin treatment in the parotid and sublingual glands of rats to detect the possible neurotoxic effect of pefloxacin. The adult female rats were treated with intraperitoneal (i.p.) injection of pefloxacin for three or seven days (at a concentration of 20 mg/100g body weight) and the serotonergic innervation pattern along with the change in mast cell number were evaluated by using histochemistry and immunohistochemistry in the parotid and sublingual glands. We found that a three-day treatment significantly increased the number of immunoreactive serotonergic nerve fibers, but after a seven-day treatment the number of serotonin positive nerve fibers decreased almost to values of the control group. The alteration of mast cell number was parallel with the changes of the serotonin positive fibers during the treatment. These results suggest that pefloxacin treatment can modify the finely controlled communication between the immune- and the peripheral nervous systems, resulting neurogenic inflammatory process. The background of this process is the altered serotonergic innervation and the increased number of activated mast cells releasing different mediators for example histamine, which can finally lead to reduced number of serotonin positive nerve fibers after a seven-day treatment of pefloxacin leading to atrophy and hypofunction of the salivary glands.


Assuntos
Antibacterianos/efeitos adversos , Mastócitos/efeitos dos fármacos , Fibras Nervosas/efeitos dos fármacos , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/inervação , Pefloxacina/efeitos adversos , Serotonina/fisiologia , Glândula Sublingual/efeitos dos fármacos , Glândula Sublingual/inervação , Animais , Contagem de Células , Feminino , Síndromes Neurotóxicas , Ratos , Ratos Wistar
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