Antibiotics In Aqueous Solution Research Articles

Construction of Co-Modified MXene/PES Catalytic Membrane for Effective Separation and Degradation of Tetracycline Antibiotics in Aqueous Solutions.

The application of antibiotics has advanced modern medicine significantly. However, the abuse and discharge of antibiotics have led to substantial antibiotic residues in water, posing great harm to natural organisms and humans. To address the problem of antibiotic degradation, this study developed a novel catalytic membrane by depositing Co catalysts onto MXene nanosheets and fabricating the polyethersulfone composite (Co@MXene/PES) using vacuum-assisted self-assembly. The dual role of MXene as both a carrier for Co atoms and an enhancer of interlayer spacing led to improved flux and catalytic degradation capabilities of the membrane. Experimental results confirmed that the Co@MXene/PES membrane effectively degraded antibiotics through peroxymonosulfate activation, achieving up to 95.51% degradation at a cobalt concentration of 0.01 mg/mL. The membrane demonstrated excellent antibacterial properties, minimal flux loss after repeated use, and robust anti-fouling performance, making it a promising solution for efficient antibiotic removal and stable water treatment.

Exploring the efficiency of nitrogenated carbon quantum dots/TiO2 S-scheme heterojunction in the photodegredation of ciprofloxacin in aqueous environments.

In this study, we developed a heterojunction photocatalyst, namely nitrogen-doped carbon quantum dots/titanium dioxide (N-CQDs/TiO2), for the effective and sustainable treatment of ciprofloxacin (CIP) antibiotic in aqueous solution. First, N-CQDs were prepared from a chitosan biopolymer with a green, facile, and effective hydrothermal carbonization technique and then anchored on the TiO2 surface via a hydrothermal process. The morphological, structural, and optical properties of the as-prepared materials were characterized by using advanced analytical techniques. The impacts of the mass percentage of N-CQDs, catalyst and CIP concentration, and pH on photocatalytic CIP degradation were investigated in depth. Comparative analyses were performed to evaluate different processes including adsorption, photolysis, and photocatalysis for the removal of CIP with TiO2 and N-CQDs/TiO2. The results revealed that N-CQDs/TiO2 exhibited the highest CIP removal efficiency of up to 83.91% within 120 min using UVA irradiation under optimized conditions (10 mg/L CIP, 0.4 g/L catalyst, and pH 5). Moreover, the carbon source used in the fabrication of N-CQDs was also considered, and lower removal efficiency was obtained when glucose was used as a carbon source instead of chitosan. This excellent improvement in CIP degradation was attributed to the ideal separation and migration of photogenerated carriers, strong redox capability, and high generation of reactive oxygen species provided by the successful construction of the N-CQDs/TiO2 S-scheme heterojunction. Scavenger experiments indicated that h+ and •OH reactive oxygen species were the predominant factors for CIP elimination in water. Overall, this study presents a green synthesis approach for N-CQDs/TiO2 heterojunction photocatalysts using natural materials, demonstrating potential as a cost-effective and efficient method for pharmaceutical degradation in water treatment applications.

Removal of levofloxacin from aqueous solutions by using micro algae: optimization, isotherm, and kinetic study

This study was focused on the response surface methodology modeling of the removal of levofloxacin residue using microalgae as adsorbent. The microalgae categories Cladophora was characterized by Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) analysis techniques. The efficacy of LEV removal was evaluated by the historical data of different variables (time, pH, algal dosage, and LEV concentration) using Central Composed Design (CCD). The predicted results of the model demonstrated that the expected responses are reasonably close to the actual data, demonstrating the efficiency of this method in producing an accurate prediction. The model was found to be significant based on its coefficient of determination, which was 0.914, along with the fitted and projected values of 0.9029 and 0.8967. Furthermore, the results of the predicted reaction optimization showed that the maximum LEV elimination could be achieved within a time of 90 min, a pH of 6 and 0.2 g/L of micro algae. The model was validated experimentally with 95.45 % of LEV elimination efficiency. In addition, it is observed that the LEV removal process followed Langmuir model and pseudo-second order kinetic in majority of the cases with R2 of 0.9959. As a result of the dead algae's simple use and high adsorption effectiveness, the results demonstrated the possible use of antibiotics in aqueous solutions.

Self-Assembly of the Porphyrin Monomer on the Surface of Fe/Graphene Material: A Novel Sensing Material for the Detection of Chloramphenicol Antibiotic in Aqueous solution.

Currently, electrochemical sensors are being developed and widely used in various fields, and new materials are being explored to enhance the precision and selectivity of the sensors. The present investigation involved the fabrication of a Fe/graphene/porphyrin nanocomposite through self-assembly, wherein the individual porphyrin molecules were arranged on the Fe/graphene nanomaterials' surface. The Fe/graphene nanoparticles were synthesized utilizing a green approach, wherein leaf extract was employed as the reducing agent. The resulting materials underwent comprehensive characterization using a range of contemporary techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy. The study's findings revealed that the nanocomposites of Fe/graphene/porphyrin comprised zero-valent iron nanoparticles, exhibiting an average particle size ranging from 15 to 60 nm. These nanoparticles were seen to be evenly dispersed across the graphene sheets. The presence of nanostructure porphyrin nanofibers, measuring 20 nm in diameter, was also shown to exhibit strong integration with the surface of the Fe/graphene nanomaterials. The electrochemical properties of the Fe/graphene/porphyrin nanocomposite were also investigated, demonstrating that the prepared material could be effectively employed as a sensing electrode in the electrochemical sensor for detecting Chloramphenicol (CAP) through CV, EIS, and DPV techniques using a three-electrode electrochemical system. Under optimal conditions, Fe/graphene/porphyrin exhibited a high current response when detecting CAPs. Electrochemical sensors created using Fe/graphene/porphyrin nanocomposite have high stability and repeatability, and they hold promise in developing sensors capable of identifying other antibiotic residues in agriculture.

Highly adsorptive removal of heavy metal, dye, and antibiotic pollutants using functionalized graphene nanosheets sono-electrochemically derived from graphitic waste

The development of highly adsorptive materials at low cost is critically important for efficient treatment of industrial wastewater. We herein report a one-step sonoelectrochemical strategy to synthesize functionalized graphene (FG) nanosheets as an effective adsorptive material using graphite waste from spent household batteries. Scanning/transmission electron and Raman microscopy studies reveal that the as-synthesized nanosheets are composed of few (2–6) graphene layers. Additionally, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses imply the presence of oxygen functional groups on the nanosheets (CO and -COOH, oxygen content of 4.29%), which are immensely beneficial for the electrostatic adsorption with heavy metals, dyes, and antibiotics in aqueous solutions. As expected, FG nanosheets exhibit potent capabilities of handling a wide range of pollutants, such as methylene blue, methyl orange, enrofloxacin, and Pb2+, with high adsorption performances (99.95% and 21.21 mg/g for Enrofloxacin, 98.93% and 119.3 mg/g for methylene blue, 95.82% and 25.67 mg/g for methyl orange, 95.56% and 86.10 mg/g for Pb2+). These findings therefore show a great promise for practical uses of the FG material as efficient adsorbents in eliminating metallic, organic, and antibiotic pollutants in water.

Unraveling the degradation of levofloxacin using highly efficient β-cyclodextrin-modified copper ferrite through peroxymonosulfate activation: Mechanistic performance and degradation pathways

In this study, a highly magnetic β-cyclodextrin-modified copper ferrite (CuFe2O4@β-CD) catalyst was developed utilizing a hydrothermal method, which was subsequently utilized to degrade Levofloxacin (LEV) antibiotic in aqueous solution via heterogeneous activation of peroxymonosulfate (PMS). The findings demonstrated that the 98.87 % degradation of LEV was achieved with CuFe2O4@β-CD/PMS, much higher than that of pure CuFe2O4/PMS (87.78 %) within a 24-minute time frame under optimal parameters ([CuFe2O4@β-CD] = 0.4 g/L, [PMS] = 0.4 mM, [LEV] = 25 mg/L, pH = 6), and CuFe2O4@β-CD/PMS was present. The rate constant of CuFe2O4@β-CD/PMS (0.1608 min−1) was much greater than that of the CuFe2O4/PMS system (0.0822 min−1). The increased availability of active sites for PMS activation may be credited to the larger surface area (189.42 m2/g) of the CuFe2O4@β-CD catalyst in comparison to the pristine CuFe2O4 (87.76 m2/g), which facilitated the improved degradation of LEV. Additionally, the impact of various reaction parameters and intervening anions on the degradation of LEV was investigated. The emergence of free radicals (SO4•−, •OH, and 1O2) was corroborated via electron paramagnetic resonance and scavenging experiments. On the basis of recognizing reaction intermediates, a hypothetical degradation mechanism for LEV was developed. PMS activation was caused by the transformation of Cu+/Cu2+ and Fe3+/Fe2+ pairs, which was accomplished via radical and non-radical pathways. Also, CuFe2O4@β-CD demonstrated exceptional stability and retained its catalytic activity after five concurrent cycles. In conclusion, the CuFe2O4@β-CD catalyst demonstrated encouraging potential in the context of purifying LEV-contaminated water.

Efficient adsorption of antibiotics in aqueous solution through ZnCl2-activated biochar derived from Spartina alterniflora

In recent years, Spartina alterniflora as an invasive species has seriously threatened the native coastal ecosystem of China. There is a lack of effective management and utilization methods towards Spartina alterniflora at present. To realize the ecological remediation and resource utilization of Spartina alterniflora, the functional biochar (BC) materials were successfully prepared using Spartina alterniflora as the substrates via the high temperature calcination method, which were utilized for efficient removal of antibiotics. The biochar was further activated by ZnCl2 (ZnBC) and optimized under different calcination temperatures and ZnCl2 dosages to improve the adsorption ability. Among these biochar materials, the ZnCl2-activated biochar obtained under the mass ratio of Spartina alterniflora to ZnCl2 of 1:5 and calcination temperature of 600 °C (ZnBC-600) exhibited the strongest adsorption performance towards sulfadiazine (SDZ) and ciprofloxacin (CIP), which can be attributed to the larger specific surface area, richer pore structure and more abundant surface oxygen-containing functional groups. Additionally, the adsorption kinetics and isotherms demonstrated that the adsorption of both SDZ and CIP onto ZnBC-600 (1:5) followed the pseudo-second-order kinetic model and Freundlich model. At the same time, the performances of Spartina alterniflora biochar derived from different biomass were compared under the condition of activation with ZnCl2, presenting the superior performance of ZnCl2 activated Spartina alterniflora biochar. Moreover, the adsorption mechanism of ZnBC-600 (1:5) was proposed, illustrating the crucial roles of effects of electrostatic attraction, pore filling, oxygen-containing groups complexation, π-π stacking and hydrogen bonding in the adsorption of antibiotics. Above all, this study not only provides a feasible strategy for the preparation of functional biochar derived from Spartina alterniflora for removing organic pollutants, but also opens up a new pathway for resource utilization of Spartina alterniflora.

Rapid discrimination and ratio quantification of mixed antibiotics in aqueous solution through integrative analysis of SERS spectra via CNN combined with NN-EN model

IntroductionAbusing antibiotic residues in the natural environment has become a severe public health and ecological environmental problem. The side effects of its biochemical and physiological consequences are severe. To avoid antibiotic contamination in water, implementing universal and rapid antibiotic residue detection technology is critical to maintaining antibiotic safety in aquatic environments. Surface-enhanced Raman spectroscopy (SERS) provides a powerful tool for identifying small molecular components with high sensitivity and selectivity. However, it remains a challenge to identify pure antibiotics from SERS spectra due to coexisting components in the mixture. ObjectivesIn this study, an intelligent analysis model for the SERS spectrum based on a deep learning algorithm was proposed for rapid identification of the antibiotic components in the mixture and quantitative determination of the ratios of these components. MethodsWe established a water environment system containing three antibiotic residues of ciprofloxacin, doxycycline, and levofloxacin. To facilitate qualitative and quantitative analysis of the SERS spectra antibiotic mixture datasets, we developed a computational framework integrating a convolutional neural network (CNN) and a non-negative elastic network (NN-EN) method. ResultsThe experimental results demonstrate that the CNN model has a recognition accuracy of 98.68%, and the interpretation analysis of Shapley Additive exPlanations (SHAP) shows that our model can specifically focus on the characteristic peak distribution. In contrast, the NN-EN model can accurately quantify each component's ratio in the mixture. ConclusionIntegrating the SERS technique assisted by the CNN combined with the NN-EN model exhibits great potential for rapid identification and high-precision quantification of antibiotic residues in aquatic environments.

A o-phenanthroline-based metal-organic framework for fluorescence sensing toward CrVI and antibiotics in aqueous phase

Herein, a novel o-phenanthroline-based ligand involving two naphthalenecarboxylate groups was first synthesized, and successfully employed to fabricate a fluorescent metal–organic framework 1 under solvothermal conditions. According to the single-crystal X-ray analysis of compound 1, the Cd(II) ions connected by organic ligands form a 2D layer structure with a unique metallacycle building unit, and adjacent 2D layers are further stacked into a 3D porous framework via numerous supramolecular interactions. Powder X-ray diffraction revealed that 1 exhibits exceptional stability in both water and common organic solvents. The fluorescence sensing experiments conducted with compound 1 toward anions and antibiotics, demonstrated its selective detection capabilities for CrVI anions (CrO42−/Cr2O72−) and nitrofuran antibiotics in aqueous solutions. Additionally, fluorescent 1 serves as an effective fluorescent probe for sensing nitro-aromatic compounds in dimethyl sulfoxide. Its robust anti-interference properties, recyclability, and resistance to water make compound 1 a promising candidate for pollutant detection in wastewater.

Construction of novel CoFe2O4/h-BN/MIL-53 (Al) magnetic nanocomposites for the removal of hazardous antibiotics from water

In this study, the CoFe2O4/hexagonal boron nitride (h-BN) nanocomposite prepared via the microwave irradiation method, was hybridized with the MIL-53 (Al) metal–organic framework. The structure and morphology of the magnetic CoFe2O4/h-BN/MIL-53(Al) nanocomposite were investigated using Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray analyzer (EDX), Brunauer-Emmett-Teller (BET) surface area analysis, vibrating sample magnetometry (VSM) and zeta potential analysis. The adsorption performance of the CoFe2O4/h-BN/MIL-53 (Al) nanocomposite as a magnetically recyclable adsorbent for removing tetracycline (TC) and ciprofloxacin (CIP) antibiotics in aqueous solutions was investigated under different influence factors, including contact time, initial drug concentration, adsorbent dosage, pH conditions, temperature and ionic strength. The results indicated that the nanocomposite adsorbed 100 % of drugs within a short time (20–––30 min), with a maximum adsorption capacity of 625.00 mg g-1and 270.27 mg g−1, respectively. Additionally, the adsorption mechanism was also discussed based on the obtained results. After the drug absorption and removal process, the nanocomposite can be easily separated and reused several times without losing its absorption activity, therefore making it an appropriate choice for removing drugs from polluted water.

Highly thermostable RhB@Zr-Eddc for the selective sensing of nitrofurazone and efficient white light emitting diode.

Highly thermostable RhB@Zr-Eddc composites with the Rhodamine B (RhB) enclosed into the nanocages of Zr-Eddc was synthesized by one-pot method under hydrothermal conditions, whose structure, morphology and stability were characterized through the X-ray powder diffractometry (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). RhB@Zr-Eddc showed the highly thermal stability up to 550°C and emitted the bright red-light emission at 605nm, which could highly selective detect the nitrofurazone (NFZ) among eleven other antibiotics in aqueous solution. Furthermore, via combining the RhB@Zr-Eddc with commercial green phosphor (Y3Al5O12:Ce3+, Ga3+), the mixture was encapsulated onto a 455nm blue LED chip, creating an ex-cellent white light emitting diode (WLED) device with the correlated colour temperature (CCT) of 4710K, luminous efficiency (LE) of 43.17lm/w and Color Rendering Index (CRI) of 89.2.

Surface plasmon resonance effect of silver decorated on BiOCl and its enhanced sunlight-active photodegradation of rhodamine B (RhB) dye and ofloxacin (OFL) antibiotic

Fast electron-hole recombination rate is the major problem concerning low photocatalytic performance of the UV-active BiOCl photocatalyst. To overcome this drawback, decoration of noble metals on the surface of semiconducting photocatalysts can be regarded as one of the promising strategies to improve the photoactivity due to a synergy of heterojunction formation and surface plasmon resonance effect. However, the huge dosage (larger than 10 wt%) of the noble metal incorporated on photocatalyst surface causes high cost in production of the final product. In this work, solvothermally grown BiOCl photocatalyst was decorated with low silver metal loading of 2.5–10 wt%. The tetragonal 2.5 wt%Ag/BiOCl photocatalyst exhibited complete photodegradation of Rhodamin B (RhB) dye and ofloxacin (OFL) antibiotic under natural solar light. The enhancement of the resultant photocatalytic efficiency is possibly due to increasing of charge carrier separation efficiency at the interface together with the formation of the Schottky barrier at the Ag/BiOCl interface so that an improvement in quantum efficiency and an increase in the photocatalytic activity are expected. In addition, well dispersion of silver on BiOCl also leads to red shift in the absorption of light toward visible regime. This is due to the local surface plasmon resonance (LSPR) effect of Ag on BiOCl surface. The synthesized Ag/BiOCl photocatalyst displays enhanced photocatalytic activity with great structural stability after five times of use indicating its excellent cycling ability. The present finding offers a new pathway to create a silver decorated BiOCl for complete removal of harmful dye and antibiotic in aqueous solution. The treatment of toxic organic pollutants in the natural water can be done very easily by utilization of the green technology based on photocatalytic method with the beneficial of abundant solar energy.

A luminescent Zn(II) metal−organic framework assembled with a thiazolothiazole chromophore for sensing mainly cobalt(II) and nitrofuran antibiotics in aqueous solutions

The accumulation of cobalt(II) and antibiotics in the environmental water system has posed a significant threat to both human health and the safety of the ecological environment. Therefore, it is of utmost importance to look for a proficient means to detect cobalt(II) and antibiotics. Herein, we introduce a luminescent Zn-MOF, constructed with a thiazolo[5,4-d]thiazole ligand that features a chromophore group, which serves as a sensor to detect cobalt(II) and antibiotics. The Crystal structure of {[Zn2(OBA)2(4bpyttz)]·2DMF} (1) (4bpyttz=2,5-bis(pyridine-4-yl)thiazolo[5,4-d]thiazole, H2OBA=4,4′-oxybis(benzoic acid)) displayed a 6-c net three-dimensional (3D) framework structure with novel topological type denoted as {44·610·8}. Moreover, luminescence sensing studies demonstrated that 1 exhibits high selectivity and multi-responsiveness of multiple ions mainly for Co2+, and nitrofuran antibiotics mainly for NZF, and NFT in an aqueous medium inducing turning-off effects. The detection limits are determined to be 1.14, 0.14, and 0.072 μM for 1, respectively. Additionally, MOF-derived fluorescence test papers and composite films were utilized for the visual detection of Co2+, NZF, and NFT, thereby expanding the potential applications of the system in real-world sensing. Furthermore, the potential luminescence quenching mechanism of MOF 1 regarding Co2+ ions and nitrofuran antibiotics could be deduced through various characterization methods.

A Europium Metal-Organic Framework and Its Polymer Composite Membrane as Switch-Off Fluorescence Sensors for Antibiotic Detection in Lake Water.

The detection of antibiotic residues is of great significance in monitoring their overuse in healthcare, livestock and poultry farming, and agricultural production. Herein, EuCl3 and 4,4'-dicarboxyl-diphenoxyethene (H2DPOE) ionothermally reacted in 1-methyl-3-butylimidazolium chloride to give a europium metal-organic framework (Eu-DPOE). Eu-DPOE shows different fluorescence quenching rates for sensing eight antibiotics under different excitation wavelengths. Eu-DPOE displays a fast response, high selectivity, and sensitivity in antibiotic detection by fluorescence quenching. Eu-DPOE can sensitively detect TCs (tetracyclines), NOR (norfloxacin), NFT (furazolidone), ODZ (ornidazole), SDZ (sulfadiazine), and CHL (chloramphenicol) with limits of detection below 0.5 μmol/L. It provides a convenient and rapid tool for sensing antibiotics in aqueous solution. The detection mechanism is a competition absorption between DPOE2- and antibiotics with the supports from powder X-ray diffraction (PXRD), UV-vis spectra, and fluorescence lifetime. With a composite membrane of poly(vinylidene fluoride) (PVDF) matrix loading Eu-DPOE (Eu-DPOE@PVDF), Eu-DPOE@PVDF exhibits a visual fluorescence response to NOR under a 254 nm UV lamp and NFT and CTC under 365 nm. Eu-DPOE@PVDF is applied in the quantitative detection of CTC, NOR, and NFT in lake water with recovery rates ranging from 88.37 to 113.8%. Totally, fluorescence-quenched Eu-DPOE@PVDF exhibits a fast response, high selectivity, and sensitivity in sensing CTC, NOR, and NFT.

Effects of a High-Intensity Electron Beam on Antibiotic in Aqueous Solution

Effects of a High-Intensity Electron Beam on Antibiotic in Aqueous Solution

Highly sensitive fluorescence detection of tetracycline in food samples using a Zn5 cluster-based zwitterionic metal-organic framework

A brilliantly stable and luminescent Zn5-cluster-based metal-organic framework, namely {[Zn5(bci)4(OH)2(SO4)2]·4H2O} (MOF 1), was successfully constructed by zwitterionic ligand H2bciCl (1,3-bis(4-carboxybenzyl)-1H-imidazol-3-ium chloride) in solvothermal condition. MOF 1 which crystallized in tetragonal crystal system P41212 space group with 8-connected bcu body-centered-cubic topology exhibits excellent organic solvent stability, water stability, and pH stability. As a new fluorescence sensor, MOF 1 can selectively, sensitively, rapidly and recyclably detect tetracycline (TCY) antibiotic in aqueous solution through fluorescence quenching effect with a low detection limit of 0.083 μM. Additionally, as a fluorescent detection material with potential practical application value, MOF 1 is able to detect TCY in chicken, egg and fish samples with excellent recovery rates. The reasonable fluorescent detection mechanism has been confirmed, which may be a combination of fluorescence resonance energy transfer (FRET) and photoelectron electron transfer (PET).

Multi-response luminescent sensor with phenylenediacetic acid and bis-triazole ligand for the detection of Cr(VI), Fe(III) and nitroimidazole antibiotics in aqueous solutions

A novel complex of [Zn(L)(HEA)]n (1) has been successfully synthesized by hydrothermal method based on the double ligands of H2HEA (H2HEA = 1,2-Phenylenediacetic acid) and L (L = 1,1′-((2,4,6-trimethyl-1,3-phenylene)bis(methylene))bis(1H-1,2,4-triazole)). The single crystal structure of the complex was analyzed by X-ray single crystal diffraction, indicating that complex 1 was stacked into a 3D crystal structure through intermolecular π···π and C-H···π weak interaction. The complex was characterized by elemental analysis, infrared spectroscopy, PXRD and TGA. Additionally, fluorescence experiments showed that complex 1 could be used as a fluorescent probe for detecting Fe(III), Cr(VI), and Metronidazole (MDZ), Ornidazole (ODZ), Dimetridazole (DTZ) in aqueous solutions. Detection limits were obtained for ions (3.2×10−7 M for Cr2O72−, 5.4×10−7 M for CrO42− and 3.6 × 10−7 M for Fe3+) and nitroimidazole antibiotics (1.3×10−7 M for MDZ, 9.7×10−8 M for ODZ and 4.4×10−8 M for DTZ). The possible fluorescence quenching mechanism has been studied in the paper.

A cross-reactive fluorescent ensemble based on perylene derivative/surfactant assemblies for discrimination of multiple aminoglycoside antibiotics in aqueous solution

Sensitive detection and discrimination of multiple aminoglycosides (AGs) hold paramount importance in the efforts to curtail antibiotic overutilization and to monitor environmental impact. The present work provides a novel discriminative sensor ensemble based on a perylene derivative and SDS assemblies that can recognize nine different aminoglycosides. The fluorescent binary ensemble emits very weak fluorescence due to the strong aggregation of perylene-based probes in SDS pre-micelles. The addition of AGs can induce fast and remarkable fluorescence enhancement. The acquisition of fluorescence variation data at three characteristic emission wavelengths enables the generation of distinctive recognition pattern to each AG. Principal component analysis reveals that the sensor ensemble can correctly identify multiple AGs in both buffered aqueous solution and in 10% human urine. The fluorescence enhancement is attributed to the disaggregation of perylene units caused by the variation of SDS assembly from pre-micelle to micelles resulting from multi-point interaction with AGs. The strategy of modulation effect on fluorescence emission of encapsulated fluorophores by surfactant assemblies has been demonstrated to be highly effective for fabricating single system-based discriminative sensors for aminoglycosides.

Copper ferrite immobilized on chitosan: A suitable photocatalyst for the removal of ciprofloxacin, ampicillin and erythromycin in aqueous solution

Copper ferrite (CuFe2O4) was immobilized on chitosan to produce CuFe2O4@Chitosan for the removal of ciprofloxacin (CIP), ampicillin (AMP), and erythromycin (ERY) in water. Characterization of CuFe2O4@Chitosan by X-ray diffraction revealed the crystallite size of 18.12 nm. The Brunauer-Emmett-Teller surface area is 9.95 m2 g−1. The vibrating sample magnetometry revealed a saturation magnetization of 37.69 emu g−1. The degradation efficiency by CuFe2O4@Chitosan towards CIP (94.6 ± 0.50%), AMP (92 ± 1.00%) and ERY (90.30 ± 0.50) presents it as a promising photocatalyst for the removal of antibiotics in aqueous solutions. Regeneration capacity showed CuFe2O4@Chitosan to be a promising photocatalyst for removal of antibiotics in water.

Reduced graphene oxide supported CoFe2O4 composites with enhanced peroxymonosulfate activation for the removal of sulfamethoxazole: Collaboration of radical and non-radical pathways

In this work, an environmentally friendly reduced graphene oxidized supported cobalt ferrite (CFO/rGO) catalyst was constructed using a hydrothermal technique to heterogeneously activate peroxymonosulfate (PMS) and utilized for the degradation of sulfamethoxazole (SMX) antibiotic in aqueous solution. The results exhibited that the complete degradation of SMX was achieved in 25 min under optimal conditions ([SMX] = 8.0 mg/L, [CFO/rGO-30%] = 0.5 g/L, [PMS] = 5.0 mM, pH = 7.0) in the presence of CFO/rGO-30%/PMS with a rate constant of 0.3076 min˗1, which was roughly 6.08 times higher compared to the CoFe2O4/PMS system (0.0506 min˗1). The enhanced degradation of SMX in the CFO/rGO-30%/PMS system might be attributed to the large surface area of the CFO/rGO-30% (98.11 m2/g) catalyst compared to the pristine CoFe2O4 (24.31 m2/g), which increased the availability of active sites for PMS activation. Furthermore, the influence of pivotal reaction parameters and interfering anions on SMX mineralization was also scrutinized. The formation of free radicals (SO4•−, •OH, and 1O2) was established through quenching experiments and electron paramagnetic resonance analysis. The degradation mechanism of SMX was speculated based on the identification of degradation intermediates and X-ray photoelectron spectroscopy spectral analysis. Mechanistic investigations suggested that the transition of Co2+/Co3+ and Fe3+/Fe2+ pairs on the catalyst surface was responsible for the PMS activation, and the SMX degradation was accomplished through radical and non-radical pathways. Furthermore, CFO/rGO-30% exhibited high stability after four consecutive cycles and maintained catalytic activity. Finally, the developed CFO/rGO-30% catalyst exhibited promising potential for the purification of SMX polluted water.