Preparation of Multistage Pore TS-1 with Enhanced Photocatalytic Activity, Including Process Studies and Artificial Neural Network Modeling for Synergy Assessment.

Antibiotic residues have been found in several aquatic ecosystems as a result of the widespread use of antibiotics in recent years, which poses a major risk to both human health and the environment. At present, photocatalytic degradation is the most effective and environmentally friendly method. Titanium silicon molecular sieve (TS-1) has been widely used as an industrial catalyst, but its photocatalytic application in wastewater treatment is limited due to its small pores and few active sites. In this paper, we report a method for preparing multistage porous TS-1 with a high specific surface area by alkali treatment. In the photocatalytic removal of CIP (ciprofloxacin) antibiotic wastewater experiments, the alkali-treated catalyst showed better performance in terms of interfacial charge transfer efficiency, which was 2.3 times higher than that of TS-1 synthesized by the conventional method, and it was found to maintain better catalytic performance in the actual water source. In addition, this research studied the effects of solution pH, contaminant concentration, and catalyst dosage on CIP degradation, while liquid chromatography-mass spectrometry (LC-MS) was used to identify intermediates in the degradation process and infer possible degradation pathways and the toxicity of CIP, and its degradation product was also analyzed using ECOSAR 2.2 software, and most of the intermediates were found to be nontoxic and nonharmful. Finally, a 3:5:1 artificial neural network model was established based on the experiments, and the relative importance of the influence of experimental conditions on the degradation rate was determined. The above results confirmed the feasibility and applicability of photocatalytic treatment of wastewater containing antibiotics using visible light excitation alkali post-treatment TS-1, which provided technical support and a theoretical basis for the photocatalytic treatment of wastewater containing antibiotics.

Green synthesis of polyethylene glycol coated, ciprofloxacin loaded CuO nanoparticles and its antibacterial activity against Staphylococcus aureus.

Antibacterial resistance requires an advanced strategy to increase the efficacy of current therapeutics in addition to the synthesis of new generations of antibiotics. In this study, copper oxide nanoparticles (CuO-NPs) were green synthesized using Moringa oleifera root extract. CuO-NPs fabricated into a form of aspartic acid-ciprofloxacin-polyethylene glycol coated copper oxide-nanotherapeutics (CIP-PEG-CuO) to improve the antibacterial activity of NPs and the efficacy of the drug with controlled cytotoxicity. These NPs were charachterized by Fourier transform infrared spectroscopy (FTIR), x-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Antibacterial screening and bacterial chemotaxis investigations demonstrated that CIP-PEG-CuO NPs show enhanced antibacterial potential against Gram-positive and Gram-negative clinically isolated pathogenic bacterial strains as compared to CuO-NPs. In ex-vivo cytotoxicity CIP-PEG-CuO-nano-formulates revealed 88% viability of Baby Hamster Kidney 21 cell lines and 90% RBCs remained intact with nano-formulations during hemolysis assay. An in-vivo studies on animal models show that Staphylococcus aureus were eradicated by this newly developed formulate from the infected skin and showed wound-healing properties. By using specially designed nanoparticles that are engineered to precisely transport antimicrobial agents, these efficient nano-drug delivery systems can target localized infections, ensure targeted delivery, enhance efficacy through increased drug penetration through physical barriers, and reduce systemic side effects for more effective treatment.

Differential effects of polystyrene microplastics on the adsorption of cadmium and ciprofloxacin by tea leaf litter-derived magnetic biochar: Influencing factors and mechanisms.

Water pollution involves the coexistence of microplastics (MPs) and traditional pollutants, and how can MPs influence the adsorption of other pollutants by biochar during the treatment process remains unclear. This study aimed to investigate the influence of polystyrene microplastics (PS MPs) on the adsorption of cadmium (Cd) and ciprofloxacin (CIP) by magnetic biochar (MTBC) in the single and binary systems. MTBC was prepared using tea leaf litter; the effects of time, pH, and salt ions on the adsorption behaviors were investigated; and X-ray photoelectronic spectroscopy (XPS) and density flooding theory analysis were conducted to elucidate the influence mechanisms. Results indicated that PS MPs reduced the pollutants adsorption by MTBC due to the heterogeneous aggregation between PS MPs and MTBC and the surface charge change of MTBC induced by PS MPs. The effects of PS MPs on heavy metals and antibiotics adsorption were distinctly different. PS MPs reduced Cd adsorption on MTBC, which were significantly influenced by the solution pH and salt ions contents, suggesting the participation of electrostatic interaction and ion exchange in the adsorption, whereas the effects of PS MPs on CIP adsorption were inconspicuous. In the hybrid system, PS MPs reduced pollutants adsorption by MTBC with 66.3% decrease for Cd and 12.8% decrease for CIP, and the more remarkable reduction for Cd was due to the predominated physical adsorption, and CIP adsorption was mainly a stable chemisorption. The influence of PS MPs could be resulted from the interaction between PS MPs and MTBC with changing the functional groups and electrostatic potential of MTBC. This study demonstrated that when using biochar to decontaminate wastewater, it is imperative to consider the antagonistic action of MPs, especially for heavy metal removal. PRACTITIONER POINTS: Magnetic biochar (MTBC) was prepared successfully using tea leaf litter. MTBC could be used for cadmium (Cd) and ciprofloxacin (CIP) removal. Polystyrene microplastics (Ps MPs) reduced Cd/CIP adsorption by MTBC. Ps MPs effects on Cd adsorption were more obvious than that of CIP. Ps MPs changed the functional groups and electrostatic potential of MTBC, thus influencing MTBC adsorption.

Desorption hysteresis of antibiotics on biochar produced at high temperature: The role of amine groups and amidation reaction.

Knowledge of antibiotic desorption from high-temperature biochar is essential for assessing their environmental risks, and for the successful application of biochar to remove antibiotics. In previous studies, irreversible pore deformation, formation of charge-assisted hydrogen bonds or amide bonds were individually proposed to explain the desorption hysteresis of antibiotics on biochars, leading to a debate on hysteresis mechanism. In this study, desorption of sulfamethoxazole (SMX), ciprofloxacin (CFX) and tetracycline (TET) on a wood chip biochar produced at 700 °C (WBC700) and its oxidized product (O-WBC700) was investigated to explore the underlying hysteresis mechanism. Significant desorption hysteresis was observed for SMX, CFX and TET on WBC700 and O-WBC700. Hysteresis index (HI) of each antibiotic was higher on O-WBC700 with more oxygen-containing groups than WBC700, and was higher at lower equilibrium concentration. HI of antibiotics on WBC700 (or O-WBC700) increased in the order of SMX < CFX < TET. The calculated adsorption enthalpy of each antibiotic on WBC700 was positive, indicating an endothermic process. These phenomena together with FTIR, XPS spectra confirmed that the desorption hysteresis mechanism of antibiotics on high-temperature biochar is the formation of amide bonds by amidation reaction, but not the pore deformation or the hydrogen bond. Moreover, antibiotic can form amide bonds with WBC700 only if the amine group with pKa > 4.0, and the HI values were positively correlated with their pKa values. Amine group of antibiotics with higher pKa value show more nucleophilicity and could form stronger amide bonds with carboxyl group of biochar. The obtained results could help to solve the debate on desorption hysteresis mechanism of antibiotics on high-temperature biochars, and provide a new insight into the role of amine groups and amidation reaction on the hysteresis.

Investigation on the Synergy between Membrane Permeabilizing Amphiphilic α-Hydrazido Acids and Commonly Used Antibiotics against Drug-Resistant Bacteria.

The growth of (multi)drug resistance in bacteria is among the most urgent global health issues. Monocationic amphiphilic α-hydrazido acid derivatives are structurally simple mimics of antimicrobial peptides (AMPs) with fewer drawbacks. Their mechanism of membrane permeabilization at subtoxic concentrations was found to begin with an initial electrostatic attraction of isolated amphiphile molecules to the phospholipid heads, followed by a rapid insertion of the apolar portions. As the accumulation into the bilayer proceeded, the membrane increased its fluidity and permeability without being subjected to major structural damage. After having ascertained that α-hydrazido acid amphiphiles do not interact with bacterial DNA, they were subjected to synergy evaluation for combinations with conventional antibiotics. Synergy was observed for combinations with tetracycline against sensitive S. aureus and E. coli, as well as with ciprofloxacin and colistin against resistant strains. Additivity with a remarkable recovery in activity of conventional antibiotics (from 2-fold to ≥32-fold) together with largely subtoxic concentrations of α-hydrazido acid derivatives was found for combinations with ciprofloxacin toward susceptible S. aureus and methicillin toward MRSa. However, no potentiation of conventional antibiotics was observed for combinations with linezolid and gentamicin against the corresponding resistant S. aureus and E. coli strains.

Heterogeneous Photocatalytic Degradation of Selected Pharmaceuticals and Personal Care Products (PPCPs) Using Tungsten Doped TiO2: Effect of the Tungsten Precursors and Solvents.

Pharmaceuticals and personal care products (PPCPs) which include antibiotics such as tetracycline (TC) and ciprofloxacin (CIP), etc., have attracted increasing attention worldwide due to their potential threat to the aquatic environment and human health. In this work, a facile sol-gel method was developed to prepare tungsten-doped TiO2 with tunable W5+/W6+ ratio for the removal of PPCPs. The influence of solvents in the synthesis of the three different tungsten precursors doped TiO2 is also taken into account. WCl6, ammonium metatungstate (AMT), and Na2WO4●2H2O not only acted as the tungsten precursors but also controlled the tungsten ratio. The photocatalyst prepared by WCl6 as the tungsten precursor and ethanol as the solvent showed the highest photodegradation performance for ciprofloxacin (CIP) and tetracycline (TC), and the photodegradation performance for tetracycline (TC) was 2.3, 2.8, and 7.8 times that of AMT, Na2WO4●2H2O as the tungsten precursors and pristine TiO2, respectively. These results were attributed to the influence of the tungsten precursors and solvents on the W5+/W6+ ratio, sample crystallinity and surface properties. This study provides an effective method for the design of tungsten-doped TiO2 with tunable W5+/W6+ ratio, which has a profound impact on future studies in the field of photocatalytic degradation of PPCPs using an environmentally friendly approach.

Sustained co-release of ciprofloxacin and dexamethasone in rabbit maxillary sinus using polyvinyl alcohol-based hydrogel microparticle.

Topical delivery to paranasal sinuses through sustained-release stents is one of the new horizons in treating chronic rhinosinusitis (CRS). This study aims to introduce and evaluate sustained co-release of encapsulated ciprofloxacin (CIP) and dexamethasone (DEX) in polyvinyl alcohol-based carriers within the maxillary sinus of rabbit animals. DEX and CIP were loaded in a tyramine-substituted polyvinyl alcohol microparticle (PVATyr MP). The mechanical stability, degradability, and sustained-release patterns of both drugs as well as cellular cytocompatibility were assessed in vitro. The PVATyr MPs were then injected into the maxillary sinus of rabbits and they were monitored weekly for 21 days. Nasal endoscopy, MRI imaging, and tissue microscopy were used to follow the changes and compared them with the control condition. Also, the concentrations of drugs were evaluated in the maxillary sinus and blood samples over the study period. Produced PVA-based MPs possessed a relatively narrow particle size distribution (CV 7.7%) with proper physical stability until 30 days of incubation. The uniform-sized PVATyr MPs and their surrounding hydrogel showed sustained-release profiles for DEX and CIP for up to 32 days in vitro. The injected drugs-loaded hydrogel showed complete clearance from the maxillary sinus of rabbits within 28 days. The concentrations of DEX and CIP in mucosal remained within the therapeutic window when measured on days 7, 14, and 21, which were well above the plasma concentrations without any pathological changes in endoscopy, MRI imaging, and histological examinations. DEX/CIP loaded PVATyr MPs provided an effective, controlled, and safe sustained-drug delivery in both in vitro and in vivo analyses at therapeutic concentrations with minimal systemic absorption, suggesting a promising treatment approach for CRS.

Noble metal-free plasmonic Cu/WO3-x@ZNC bi-functional composite for ciprofloxacin photocatalytic degradation and photothermal water evaporation via visible-infrared exposure.

Herein, coupling of noble metal-free plasmonic copper nanoparticles with tungsten suboxide and supporting on zeolite nanoclay (Cu/WO3-x@ZNC) composite will be introduced for bi-functional photocatalytic ciprofloxacin (CIP) degradation and water photothermal evaporation under visible/infrared (Vis/IR) exposure. Reduced band-gap of WO3-x via oxygen vacancies creation and localized surface plasmon resonance (LSPR) formation by Cu nanoparticles contributed significantly the extension and intensification of composite's photo-absorption range. Furthermore, small mesoporous structure of ZNC enhanced CIP adsorption and charge carriers separation where the reported photocatalytic efficiencies were 88.3 and 81.7% upon IR and Vis light exposure respectively. It was evidenced that plasmonic hot electrons (e-.s) and hydroxyl radicals (OH•-) performed the basic functions of the photocatalytic process. At the other side, oxygen vacancies existence, plasmonic effect, and confining thermal characteristics of WO3-x, Cu, and ZNC correspondingly induced water photothermal evaporation with efficiencies up to 97.5 and 72.8% under IR and Vis illumination respectively. This work introduces synthesis of a novel bi-functional photocatalytic-photothermal composite by metal sub-oxide and non-noble metal plasmonic coupling and supporting on naturally-derived carrier for water restoration under broad spectral exposure.

Revealing the vital role of sulfur site on the surface of pyrite in 1O2 formation for promoting ciprofloxacin degradation via peracetic acid activation.

Pyrite has been widely utilized to activate oxidants for water treatment, yet the regulation of reactive oxygen species (ROS) by sulfur sites on its surface has been overlooked. In this study, the surface sulfur sites were regulated by thermal modification of natural pyrite in the N2 atmosphere (denoted as P-X, where X represented pyrolysis temperatures ranging from 400 to 700 °C), and these modified pyrites were employed to activate peracetic acid (PAA) for ciprofloxacin (CIP) degradation. The results revealed that the degradation rate of CIP increased as the reduced sulfur content increased, with the P600/PAA system achieving the highest apparent degradation rate (kobs = 0.0999 min-1). Quenching experiments and electron paramagnetic resonance (EPR) analysis identified various ROS involved in the P-X/PAA system, with hydroxyl radical (·OH) and singlet oxygen (1O2) identified as dominant reactive species responsible for CIP degradation. The reduced sulfur sites served as the primary active sites facilitating the conversion of organic radicals (·CH3C(O)OO) into superoxide radicals (·O2-) and 1O2. Furthermore, the P600/PAA system demonstrated robust adaptability under both acidic and neutral pH conditions, efficiently degrading CIP even in the presence of complex matrices such as Cl-, NO3-, SO42-, NH4+, or humic acid (HA) in water bodies, although HCO3- was found to inhibit CIP degradation. This study significantly enhances our understanding of the interaction between reduced sulfur sites and ROS in PAA-based advanced oxidation processes (AOPs), offering a promising technology for efficient antibiotic treatment in water purification.

Integrated electrochemical-adsorption for simultaneous removal of pharmaceuticals from water: Process optimization and synergistic insights.

Water contamination with pharmaceuticals has become an evident environmental challenge. Treatment processes such as electrochemical oxidation (EO) and adsorption have limitations in the simultaneous removal of pharmaceuticals from water. Therefore, this study examined the potential of coupled process (EO followed by adsorption) in binary pharmaceuticals (acetaminophen (ACM) + ciprofloxacin (CIP)) removal from water, with an emphasis on coupled process optimization. Consequently, optimized coupled process conditions including current density (22 mA/cm2), pH (5.5), EO time (40 min), adsorbent dose (0.1 g/L) and adsorption time (60 min) were obtained. Under optimal conditions, removal efficiencies of 94.6% (ACM)+92% (CIP), 94.07% (ACM)+91.15% (CIP), and > 99.8% (ACM + CIP) were recorded for 20 mg/L (ACM + CIP) removal in EO, adsorption and EO + adsorption, respectively. Further, the coupled process was employed in multiple pharmaceuticals (20 mg/L of ACM + CIP + ATN (atenolol) + AMX (amoxicillin)) removal from water and removal of > 97.56% (ACM + CIP + ATN + AMX) was achieved. Removal efficiencies of ACM (83.35%) + CIP (73.1%) + ATN (68.52%) + AMX (63.05%) and ACM (80.37%) + CIP (66.5%) + ATN (73.07%) + AMX (60.5%) were obtained in EO and adsorption, respectively. The noted lower removal efficiencies in EO and adsorption are associated with the diverse nature of the pharmaceuticals, limited adsorbent active sites, and the shared utilization of reactive oxygen species (ROS) among the pharmaceuticals in EO. The total organic carbon (TOC) removal of 40.24%, and 99% and chemical oxygen demand (COD) removal of 72.45%, and 99.6% were obtained under optimal conditions of EO, and coupled process, respectively. These findings indicate that the pharmaceuticals are only partially mineralized in EO and the subsequent adsorption effectively eliminated the remaining target pharmaceuticals, and degradation by-products from water. Additionally, integrating EO with adsorption reduced the electrical energy consumption of the EO process from 31.6 kWh/m³ to 6 kWh/m³ under optimal conditions. Overall, coupling EO with adsorption offers the utmost advantages when removing multiple pharmaceuticals from complex water matrices.

Boosted visible-light-induced photo-Fenton degradation of organic pollutants over a novel direct Z-scheme NH2-MIL-125(Ti)@FeOCl heterojunction catalyst.

Improving the charge separation, charge transfer, and effective utilization is crucial in a photocatalysis system. Herein, we prepared a novel direct Z-scheme NH2-MIL-125(Ti)@FeOCl (Ti-MOF@FeOCl) composite photocatalyst through a simple method. The prepared composite catalyst was utilized in the photo-Fenton degradation of Rhodamine B (RhB) and ciprofloxacin (CIP). The Ti-MOF@FeOCl (10FeTi-MOF) catalyst exhibited the highest catalytic performance and degraded 99.1 and 66% of RhB and CIP, respectively. However, the pure NH2-MIL-125(Ti) (Ti-MOF) and FeOCl catalysts achieved only 50 and 92% of RhB and 50 and 37% of CIP, respectively. The higher catalytic activities of the Ti-MOF@FeOCl composite catalyst could be due to the electronic structure improvements, photoinduced charge separations, and charge transfer abilities in the catalyst system. The composite catalysts have also enhanced adsorption and visible light-responsive properties, allowing for efficient degradation. Furthermore, the electron paramagnetic resonance (EPR) signals, the reactive species trapping experiments, and Mott-Schottky (M - S) measurements revealed that the photogenerated superoxide radical (•O2-), hydroxyl radical (•OH), and holes (h+) played a vital role in the degradation process. The results also demonstrated that the Ti-MOF@FeOCl heterojunction composite catalysts could be a promising photo-Fenton catalyst system for the environmental remediation. Environmental implications The discharging of toxic contaminants such as organic dyes, antibiotics, and other emerging pollutants to the environment deteriorates the ecosystem. Specifically, the residues of organic pollutants recognized as a threat to ecosystem and a cause for carcinogenic effects. Among them, ciprofloxacin is one of antibiotics which has biological resistance, and metabolize partially in the human or animal bodies. It is also difficult to degrade ciprofloxacin completely with traditional treatment methods. Similarly, organic dyes are also toxic and a cause for carcinogenic effects. Therefore, effective degradation of organic pollutants such as RhB and ciprofloxacin with appropriate method is crucial.

A 3D bioprinted antibacterial hydrogel dressing of gelatin/sodium alginate loaded with ciprofloxacin hydrochloride.

Skin plays a crucial role in human physiological functions, however, it was vulnerable to bacterial infection which delayed wound healing. Nowadays, designing an individual wound dressing with good biocompatibility and sustaining anti-infection capability for healing of chronic wounds are still challenging. In this study, various concentrations of the ciprofloxacin (CIP) were mixed with gelatine (Gel)/sodium alginate (SA) solution to prepare Gel/SA/CIP (GAC) bioinks, following the fabrication of GAC scaffold by an extrusion 3D bioprinting technology. The results showed that the GAC bioinks had good printability and the printed GAC scaffolds double-crosslinked by EDC/NHS and CaCl2 had rich porous structure with appropriate pore size, which were conducive to drug release and cell growth. It demonstrated that the CIP could be rapidly released by 70% in 5 min, which endowed the GAC composite scaffolds with an excellent antibacterial ability. Especially, the antibacterial activities of GAC7.5 against Escherichia coli and Staphylococcus aureus within 24 h were even close to 100%, and the inhibition zones were still maintained 14.78 ± 0.40 mm and 14.78 ± 0.40 mm, respectively, after 24 h. Meanwhile, GAC7.5 also demonstrated impressive biocompatibility which can promote the growth and migration of L929 and accelerate wound healing. Overall, the GAC7.5 3D bioprinting scaffold could be used as a potential skin dressing for susceptible wounds with excellent antibacterial activity and good biocompatibility to meet urgent clinical needs.

A microbiome-biochar composite synergistically eliminates the environmental risks of antibiotic mixtures and their toxic byproducts.

This study developed a continuous reactor system employing a hybrid hydrogel composite synthesized using a complex sludge microbiome and an adsorbent (HSA). This HSA-based system effectively eliminated the environmental risks associated with a mixture of the antibiotics ciprofloxacin and sulfamethoxazole, which exhibited higher toxicity in combination than individually at environmentally relevant levels. Analytical chemistry experiments revealed the in-situ generation of various byproducts (BPs) within the bioreactor system, with two of these BPs recording toxicity levels that surpassed those of their parent compound. The HSA approach successfully prevented the functional microbiome from being washed out of the reactor, while HSA efficiently removed antibiotic residues in their original and BP forms through synergistic adsorptive and biotransformation mechanisms, ultimately reducing the overall ecotoxicity. The use of HSA thus demonstrates promise not only as a mean to reduce the threat posed by toxic antibiotic residues to aquatic ecosystems but also as a practical solution to operational challenges, such as biomass loss/washout, that are frequently encountered in various environmental bioprocesses.

Effect of environmental factors on adsorption of ciprofloxacin from wastewater by microwave alkali modified fly ash.

Antibiotics, as emerging persistent pollutants, pose significant threats to human health. The effective and low-cost removal of ciprofloxacin (CIP) from wastewater has become an important research focus. In this study, fly ash (FA) was used as the raw material, and modified fly ash (MFA) was prepared by varying microwave power, alkali concentration, and immersion time to investigate its adsorption characteristics for CIP. Results showed that the optimal preparation conditions for MFA with the most effective adsorption of CIP, using the Box-Behnken response surface methodology, were a microwave power of 480 W, an alkali concentration of 1.5 mol/L, and a modification time of 3 h. Scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analyses revealed that after modification, the glassy structure of FA is destroyed, the specific surface area is increased, and obvious hydroxyl O-H absorption peaks appear. Both FA and MFA exhibited adsorption processes for CIP that conformed to pseudo-second-order kinetics and the Langmuir equation. Maximum adsorption of CIP (9.61 and 12.67 mg/g) was achieved at pH = 6. With increasing temperature, the adsorption capacity of both FA and MFA for CIP decreased, indicating an exothermic process. The adsorption capacity of CIP decreased with increasing ion concentration, with the impact order of ions being Al3+ > Ca2+ > Na+. The results show that pore filling, electrostatic interaction, ion exchange and complexation are the main ways of CIP adsorption by FA. Microwave alkali modified fly ash is an economical and efficient adsorbent for CIP removal in water, realizing the purpose of "treating waste with waste". This study provides a scientific basis for controlling CIP treatment in wastewater.

Green adsorbents for pharmaceutics removal from urine: Analysis of isotherms, kinetics, adsorption interactions, cost estimation, and environmental impact.

Husks of rice (RH), coffee (CH), and cholupa (CLH) were used to produce natural adsorbents. The natural adsorbents were used to remove pharmaceuticals such as diclofenac, ciprofloxacin, and acetaminophen in a mixture of distilled water. However, CH stood out for its efficiency in removing ciprofloxacin (74%) due to the higher concentration of acidic groups, as indicated by the Boehm method. In addition, CH removed 86% of ciprofloxacin individually. Therefore, CH was selected and used to remove other fluoroquinolones, such as levofloxacin and Norfloxacin. Although electrostatic interactions favored removals, better removal was observed for ciprofloxacin due to its smaller molecular volume. Then, ciprofloxacin was selected, and the effect of pH, matrix, and adsorbent doses were evaluated. In this way, using a pH of 6.2 in urine with a dose of 1.5 g L-1, it is possible to adsorb CIP concentrations in the range (0.0050-0.42 mmol L-1). Subsequently, the high R2 values and low percentages of APE and Δq indicated better fits for pseudo-second-order kinetics, suggesting a two-stage adsorption. At the same time, the Langmuir isotherm recommends a monolayer adsorption with a Qm of 25.2 mg g-1. In addition, a cost of 0.373 USD/g CIP was estimated for the process, where the material can be reused up to 4 times with a CIP removal in the urine of 51%. Consequently, thermodynamics analysis showed an exothermic and spontaneous process with high disorder. Furthermore, changes in FTIR analysis after adsorption suggest that CH in removing CIP in urine involves electrostatic attractions, hydrogen bonds and π-π interactions. In addition, the life cycle analysis presents, for the 11 categories evaluated, a lower environmental impact of the CIP removal in urine with CH than for the preparation of adsorbent, confirming that the adsorption process is more environmentally friendly than materials synthesis or other alternatives of treatments. Furthermore, future directions of the study based on real applications were proposed.

Removal of fluoroquinolone antibiotic and sulfonated dye by functionalized Persea americana seed powder: Appraisal on phase transfer kinetics, equilibrium, economics, and applications in rural settings.

The study focuses on reactive orange 16 (RO16), a sulfonated dye, and ciprofloxacin (CiP), a fluoroquinolone antibiotic treatment from aquatic surface by adsorption. The functionalized Persea americana seed powder (PASP) was developed by acid hydrolysis technique and investigated for RO16 and CiP removal in batch scale at different concentrations for CiP and RO16, pH (2-8), contact duration and temperature (303-318K). Utilizing a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDAX), the generated native PASP were assessed for their morphological characteristics. Fourier transform infrared (FTIR) spectroscopy was applied to examine the performing characteristics of PASP. Experimental findings with four kinetic mathematical models allowed the estimation of the process involved in the biosorption. The most effective agreement was explained by the pseudo-second-order model and Sips isotherm (Cip = 34.603 mg/g and RO16 = 30.357 mg/g) at 303K temperature. For Cip Process economics of the biosorbent was done, and it was observed that it was less than the readily market-available activated carbon.

Molecular Mechanism of Ciprofloxacin Translocation Through the Major Diffusion Channels of the ESKAPE Pathogens Klebsiella pneumoniae and Enterobacter cloacae.

Experimental studies on the translocation and accumulation of antibiotics in Gram-negative bacteria have revealed details of the properties that allow efficient permeation through bacterial outer membrane porins. Among the major outer membrane diffusion channels, OmpF has been extensively studied to understand the antibiotic translocation process. In a few cases, this knowledge has also helped to improve the efficacy of existing antibacterial molecules. However, the extension of these strategies to enhance the efficacy of other existing and novel drugs require comprehensive molecular insight into the permeation process and an understanding of how antibiotic and channel properties influence the effective permeation rates. Previous studies have investigated how differences in antibiotic charge distribution can influence the observed permeation pathways through the OmpF channel, and have shown that the dynamics of the L3 loop can play a dominant role in the permeation process. Here, we perform all-atom simulations of the OmpF orthologs, OmpE35 from Enterobacter cloacae and OmpK35 from Klebsiella pneumoniae. Unbiased simulations of the porins and biased simulations of the ciprofloxacin permeation processes through these channels provide insight into the differences in the permeation pathway and energetics. In addition, we show that similar to the OmpF channel, antibiotic-induced dynamics of the L3 loop are also operative in the orthologs. However, the sequence and structural differences, influence the extent of the L3 loop fluctuations with OmpK35 showing greater stability in unbiased runs and subdued fluctuations in simulations with ciprofloxacin.

Regulating cobalt-nitrogen function centers via Cu incorporation enhances ciprofloxacin destruction through peroxymonosulfate activation.

Metal-nitrogen (M-N) coupling has shown promise as a catalytic active component for various reactions. However, the regulation of heterogeneous catalytic materials with M-N coupling for peroxymonosulfate (PMS) activation to enhance the degradation efficiency and reusability of antibiotics remains a challenge. In this study, an efficient modulation of M-N coupling was achieved through the incorporation of Cu into Co4N to form a Cu-Co4N composite with sea urchin-like morphology assembled by numerous nano-needles using hydrothermal and nitriding processes. This modulation led to enhanced PMS activation for ciprofloxacin (CIP) degradation. The Cu-Co4N/PMS system demonstrated exceptional removal efficiency with a degradation rate of 95.85% within 30 min and can be reused for five time without obvious loss of its initial activity. Additionally, the catalyst displayed a high capacity for degrading various challenging organic pollutants, as well as remarkable stability, resistance to interferences, and adaptability to pH changes. The synergistic effect between Co and Cu facilitated multiple redox cycles, resulting in the generation of reactive oxidized species. The primary active species involved in the catalytic degradation process included 1O2, SO4•-, O2•-, •OH, and e-, with 1O2 and SO4•- playing the most significant roles. The degradation pathways and toxicity of the intermediates for CIP were unveiled. This study offers valuable insights into the regulation of M-N centers for degrading antibiotics through PMS activation.

Synergistic photocatalytic degradation of ciprofloxacin under natural sunlight using hot dip galvanization and medical incineration waste residues.

To improve the photodegradation capacity, for the first time, a simple yet efficient photocatalyst was prepared by solely employing hot dip galvanization waste (GW) and fly ash (FA) disposed from medical waste incinerators. Impressively, the as-synthesized photocatalyst (GW-FA) in the ratio 3:1 displayed an outstanding ciprofloxacin degradation efficiency of 98.3% under natural sunlight within 60 min and possessed superior reusability. Herein, adjusting the amount of GW evidenced effective tuning of the electronic band structure and increased active sites. Detailed microscopic morphology, chemical structure, magnetic, and optical properties of GW-FA were studied by UV-DRS, FESEM-EDX, HRTEM, XRD, XPS, ESR, VSM, and AFM, which confirmed the successful fabrication of GW-FA and their outstanding ability to reduce the recombination rate. Besides, the effects of crucial experimental parameters (concentration, pH, and photocatalyst loading) on ciprofloxacin degradation were examined using RSM-BBD. Further, OH• was manifested to be the main active species for the photodegradation of ciprofloxacin. Eventually, GC-MS analysis was employed to deduce plausible photodegradation pathways, and ICP-AES analysis proved that the concentration of leached heavy metals was lower than that of the standard limits for irrigation water. This work establishes a new route for effectively reutilizing waste generated from medical waste incinerators and galvanization industries as a photocatalyst, which otherwise would be disposed in landfills.

Adsorption of ciprofloxacin from aqueous solutions using cellulose-based adsorbents prepared by sol-gel method.

Ciprofloxacin (CIP) is one of the most widely used antibiotics to treat bacterial infections. Consequently, there is concern that it may contaminate water resources due to its high usage level. It is therefore necessary to monitor, trace, and reduce exposure to these antibiotic residues. In the current study, the extraction of CIP from water was performed using a green adsorbent material based on cellulose/polyvinyl alcohol (PVA) decorated with mixed metal oxides (MMO). This cellulose/MMO/PVA adsorbent was synthesized using a simple sol-gel method. The prepared adsorbent materials were then characterized using a range of methods, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, gas adsorption analysis, X-ray diffraction, and Fourier Transform infrared. The impact of pH, adsorbent dose, contact time, and CIP concentration on ciprofloxacin extraction were examined. The equilibrium and kinetic adsorption data were well described using the Freundlich model (R2 = 0.965). The optimum conditions for CIP adsorption were: pH = 4.5; adsorbent dosage = 0.55 g·L-1; contact time = 83 min; and initial CIP concentration = 2 mg·L-1. The adsorption capacity of the cellulose/MMO/PVA adsorbent for CIP removal was ∼19 mg·g-1 (CIP removal = 86.48 %). This study shows that cellulose/MMO/PVA adsorbents have potential for removing contaminants from aqueous environments.