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Ciprofloxacin (CIP) is considered as a biological resistant pollutant. The CoFe O /activated carbon@chitosan (CoFe O /AC@Ch) prepared as a new magnetic nanobiocomposite and used for adsorption of CIP. CoFe O /AC@Ch was characterized by Fourier transform-infrared (FT-IR), field emission scanning electron microscope (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET) surface area measurements. The pH value of the nanobiocomposite was estimated to be 6.4 by solid addition method. The prepared magnetic nanobiocomposites can be separated easily from water by an external magnet and reused. The effect of CIP concentration (10-30 mg/L), adsorbent dosage (12-100 mg/L), contact time (5-30 min) and pH (3-11) as independent variables on ciprofloxacin removal efficiency was evaluated. Optimum conditions were obtained in CIP concentration: 10 mg/L, adsorbent dosage: 100 mg/L, contact time: 15 min and pH: 5. In this condition, maximum CIP removal was obtained as 93.5%. The kinetic and isotherm equations showed that the process of adsorption followed the pseudo-second order kinetic and Langmuir isotherm. The results indicate that the prepared magnetic nanobiocomposite can be used as good adsorbent for the removal of CIP from aqueous solution and can be also recycled.

This work reports a novel one-pot hydrothermal synthesis of N-CQDs using Solanum nigrum L . as sustainable carbon source and triethylamine as nitrogen provider. The resulting N-CQDs were systematically characterized with TEM, SEM, FT-IR, XPS, XRD, and UV–Visible. Significantly, the N-CQDs exhibited substantial antimicrobial efficacy against both S. aureus and E. coli bacterial strains, with minimum inhibitory concentration values of 1.2 mg/mL and 1.1 mg/mL, respectively. Moreover, the N-CQDs demonstrated pronounced fluorescence enhancement upon interaction with ciprofloxacin, displaying exceptional selectivity and sensitivity, with a calculated LOD of 316 nM. The feasibility of employing N-CQDs as fluorescent probes for ciprofloxacin detection was systematically validated through practical application in honey analysis. This study introduces a novel approach for the fabrication of N-CQDs derived from natural botanical sources, underscoring their potential dual functionality as fluorescent sensors and antimicrobial materials.

The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring bacterial niches, resistance of Escherichia coli to the antibiotic ciprofloxacin developed within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing of the resistant organisms revealed that four functional single-nucleotide polymorphisms attained fixation. Knowledge about the rapid emergence of antibiotic resistance in the heterogeneous conditions within the mammalian body may be helpful in understanding the emergence of drug resistance during cancer chemotherapy.

Detecting antibiotics in the milk supply chain is crucial to protect humans from allergic reactions, as well as preventing the build-up of antibiotic resistance. The dairy industry has controls in place at processing facilities, but controls on dairy farms are limited to manual devices. Errors in the use of these manual devices can result in severe financial harm to the farms. This illustrates an urgent need for automated methods of detecting antibiotics on a dairy farm, to prevent the shipment of milk containing antibiotics. This work introduces the microchip capillary electrophoresis dairy device, a low-cost system that utilizes microchip capillary electrophoresis as well as fluorescence spectroscopy for the detection of ciprofloxacin contained in milk. The microchip capillary electrophoresis dairy device is operated under antibiotic-absent conditions, with ciprofloxacin not present in a milk sample, and antibiotic-present conditions, with ciprofloxacin present in a milk sample. The response curve for the microchip capillary electrophoresis dairy device is found through experimental operation with varied concentrations of ciprofloxacin. The sensitivity and limit of detection are quantified for the microchip capillary electrophoresis dairy device.

This study demonstrates a one-step hydrothermal synthesis of bright yellow phosphorus-doped carbon quantum dots (P-CQDs) using Caesalpinia sappan L. as carbon source. Comprehensive characterization through TEM, XPS, UV-Vis and FTIRspectroscopy confirmed the successful formation of P-CQDs. The obtained P-CQDs exhibited exceptional selectivity and was capable of detecting ciprofloxacin across a wide linear range of 0.01–0.1 µM, with a LOD determined to be 2.06 nM. Antimicrobial assays revealed MIC values of 7.14 µg/mL and 8.33 µg/mL against S. aureus and E. coli , respectively. Practical application studies confirmed their efficacy for rapid CIP detection in milk samples, establishing a novel sensing platform for food safety monitoring. This work provides valuable insights into the multifunctional applications of carbon dots in food chemistry and biomedical fields.

The widespread residual ciprofloxacin (CIP) poses severe environmental and health risks, demanding efficient detection methods. Herein, a Zr-Tb bimetallic MOF (ZTM) was green-synthesized via a room-temperature aqueous route with disodium terephthalate as ligand, and developed as a ratiometric fluorescent probe for CIP detection. Structural characterization confirmed Tb was successfully incorporated into the Zr-MOF framework, endowing ZTM with high stability and excellent luminescence. The absorption edge of ZTM (320-330 nm) overlapped with CIP's 330 nm absorption peak, so 327 nm was selected as the excitation wavelength. Under this excitation, ZTM showed a strong Tb emission at 657 nm; upon CIP addition, the 657 nm peak was quenched, while the 491 nm emission was enhanced, realizing a distinct ratiometric response. The ratio I /I was linear with CIP concentration (0.5-25 μM, R = 0.992), with a limit of detection far below the statutory 30 μM limit (0.16 μM). ZTM also exhibited excellent selectivity, good pH tolerance (5.0-8.0) and rapid response (1 min). Mechanism analysis revealed that the response was mainly due to the inner filter effect (IFE) between ZTM and CIP. This work provides a green-synthesized MOF probe for sensitive and selective CIP detection in environmental samples.

In this work, Mn2O3/Fe2O3 (MFO) was synthesized and used to activate monopersulfate (MPS) for the degradation of ciprofloxacin (CIP). The effect of several parameters was studied on CIP degradation. Under the optimum conditions (pH = 6.3 (natural pH), MFO = 300 mg/L and MPS = 2 mM), around 92% of CIP was decomposed. Nitrite, phosphate and bicarbonate ions had a strong inhibitory effect on the MFO/MPS process while the effect of chloride and nitrate ions was neutral. The catalytic activity of MFO was also studied by other chemical oxidants such as peroxydisulfate, periodate, hydrogen peroxide, percarbonate and peracetic acid. Scavenging tests showed that the role of sulfate radicals is more than hydroxyl radicals. MFO exhibited high catalytic activity in four recycling with insignificant leaching of Mn and Fe. During CIP oxidation, 45.5% carbon mineralization occurred and antibacterial activity of treated CIP solution was reduced. Finally, MFO/MPS was applied on actual wastewater (hospital effluent) and the results showed that MFO/MPS can be considered as a practical method for the treatment of contaminated water with emerging pollutants.

Hospital effluents represent an important source for the release of antibiotics and antibiotic resistant bacteria into the environment. This study aims to determine concentrations of various antibiotics in wastewater before and after wastewater treatment in a rural hospital (60 km from the center of Hanoi) and in an urban hospital (in the center of Hanoi) in Vietnam, and it aims to explore the relationship between antibiotic concentrations in wastewater before wastewater treatment and quantities of antibiotics used in the rural hospital, over a period of one year in 2013. Water samples were collected using continuous sampling for 24 h in the last week of every month. The data on quantities of antibiotics delivered to all inpatient wards were collected from the Pharmacy department in the rural hospital. Solid-phase extraction and high performance liquid chromatography-tandem mass spectrometry were used for chemical analysis. Significant concentrations of antibiotics were present in the wastewater both before and after wastewater treatment of both the rural and the urban hospital. Ciprofloxacin was detected at the highest concentrations in the rural hospital’s wastewater (before treatment: mean = 42.8 µg/L; after treatment: mean = 21.5 µg/L). Metronidazole was detected at the highest concentrations in the urban hospital’s wastewater (before treatment: mean = 36.5 µg/L; after treatment: mean = 14.8 µg/L). A significant correlation between antibiotic concentrations in wastewater before treatment and quantities of antibiotics used in the rural hospital was found for ciprofloxacin (r = 0.78; p = 0.01) and metronidazole (r = 0.99; p < 0.001).

The transport of carbamazepine, ciprofloxacin and sulfamethoxazole in the different pores of activated carbon in an aqueous solution is a dynamic process that is entirely dependent on the intrinsic parameters of these molecules and of the adsorbent. The macroscopic processes that take place are analyzed by interfacial diffusion and reaction models. Modeling of the experimental kinetic curves obtained following batch treatment of each solute at 2 µg/L in tap water showed (i) that the transport and sorption rates were controlled by external diffusion and intraparticle diffusion and (ii) that the effective diffusion coefficient for each solute, with the surface and pore diffusion coefficients, were linked by a linear relationship. A statistical analysis of the experimental data established correlations between the diffusional parameters and some geometrical parameters of these three molecules. Given the major discontinuities observed in the adsorption kinetics, the modeling of the experimental data required the use of traditional kinetic models, as well as a new kinetic model composed of the pseudo first or second order model and a sigmoidal expression. The predictions of this model were excellent. The solubility of each molecule below 60 °C was formulated by an empirical expression.

Photochemical degradation of fluoroquinolone ciprofloxacin (CIP) in water by UV and UV/H 2 O 2 were investigated. The degradation rate of CIP was affected by pH, H 2 O 2 dosage, as well as the presence of other inorganic components. The optimized pH value and H 2 O 2 concentration were 7.0 and 5 mM. Carbonate and nitrate both impeded CIP degradation. According to liquid chromatography–tandem mass spectrometry analysis, four and 16 products were identified in UV and UV/H 2 O 2 system, respectively. Proposed degradation pathways suggest that reactions including the piperazinyl substituent, quinolone moiety, and cyclopropyl group lead to the photochemical degradation of CIP. Toxicity of products assessed by Vibrio qinghaiensis demonstrated that UV/H 2 O 2 process was more capable on controlling the toxicity of intermediates in CIP degradation than UV process.