A novel and sustainable composite of L@PSAC for superior removal of pharmaceuticals from different water matrices: Production, characterization, and application.

This study endeavors to develop cost-effective environmentally friendly technology for removing harmful residual pharmaceuticals from water and wastewater by utilizing the effective adsorption of pistachio shell (PS) biochar and the degradation potency of laccase immobilized on the biochar (L@PSAC). The carbonatization and activation of the shells were optimized regarding temperature, time, and NH4NO3/PS ratio. This step yielded an optimum PS biochar (PSAC) with the highest porosity and surface area treated at 700 °C for 3 h using an NH4NO3/PS ratio of 3% wt. The immobilization of laccase onto PSAC (L@PSAC) was at its best level at pH 5, 60 U/g, and 30 °C. The optimum L@PSAC maintained a high level of enzyme activity over two months. Almost a complete removal (>99%) of diclofenac, carbamazepine, and ciprofloxacin in Milli-Q (MQ) water and wastewater was achieved. Adsorption was responsible for >80% of the removal and the rest was facilitated by laccase degradation. L@PSAC maintained effective removal of pharmaceuticals of ≥60% for up to six treatment cycles underscoring the promising application of this material for wastewater treatment. These results indicate that activated carbon derived from the pistachio shell could potentially be utilized as a carrier and adsorbent to efficiently remove pharmaceutical compounds. This enzymatic physical elimination approach has the potential to be used on a large-scale.

Transport of Carbamazepine, Ciprofloxacin and Sulfamethoxazole in Activated Carbon: Solubility and Relationships between Structure and Diffusional Parameters.

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.

Differentiation of isomeric metabolites of carbamazepine based on acid-base properties; Experimental vs theoretical approach.

Metabolism of carbamazepine is complex and leads to the three isomeric derivatives whose occurrence is dependent on the type of sample material. Their unambiguous differentiation is overall important. In this work, the qualitative analysis of 2-hydroxycarbamazepine, 3-hydroxycrbamazepine and carbamazepine-10,11-epoxide was attempted for the first time using capillary zone electrophoresis, based on the models linking electrophoretic mobility with pKa value determining the acidity of the hydroxyl groups. For this purpose, pKa values ​​were determined using electrophoretic and theoretical methods, and then the compliance of the obtained mobility models with the measured values ​​was analyzed. Despite the slight difference in acidity ​​(0.3-0.4 pH unit), the obtained results prove that the correct identification of the metabolites under consideration, and reliable prediction of the selectivity of their separation, are possible on the basis of experimentally determined pKa values, even with highly simplified methods assuming the lack of certain data. However, it is important to choose the optimal pH value, which should be close to pKa. On the other hand, worse results were obtained for the theoretically determined mobilities, which differed significantly from the experimental values. An attempt was also made to explain the acidity of hydroxycarbamazepines and the associated thermodynamic parameters - deprotonation enthalpy and entropy, with respect to their structure. The lack of intramolecular hydrogen bonds and the significant contribution of entropic effects stabilizing the protonated form seems to be significant. The higher pKa value for CBZ-2-OH probably results from the stronger effect of the energetically unfavorable organization of solvent dipoles due to ionization.

Removal of Persistent Sulfamethoxazole and Carbamazepine from Water by Horseradish Peroxidase Encapsulated into Poly(Vinyl Chloride) Electrospun Fibers.

Enzymatic conversion of pharmaceutically active ingredients (API), using immobilized enzymes should be considered as a promising industrial tool due to improved reusability and stability of the biocatalysts at harsh process conditions. Therefore, in this study horseradish peroxidase was immobilized into sodium alginate capsules and then trapped into poly(vinyl chloride) electrospun fibers to provide additional enzyme stabilization and protection against the negative effect of harsh process conditions. Due to encapsulation immobilization, 100% of immobilization yield was achieved leading to loading of 25 µg of enzyme in 1 mg of the support. Immobilized in such a way, enzyme showed over 80% activity retention. Further, only slight changes in kinetic parameters of free (Km = 1.54 mM) and immobilized horseradish peroxidase (Km = 1.83 mM) were noticed, indicating retention of high catalytic properties and high substrate affinity by encapsulated biocatalyst. Encapsulated horseradish peroxidase was tested in biodegradation of two frequently occurring in wastewater API, sulfamethoxazole (antibiotic) and carbamazepine (anticonvulsant). Over 80% of both pharmaceutics was removed by immobilized enzyme after 24 h of the process from the solution at a concentration of 1 mg/L, under optimal conditions, which were found to be pH 7, temperature 25 °C and 2 mM of H2O2. However, even from 10 mg/L solutions, it was possible to remove over 40% of both pharmaceuticals. Finally, the reusability and storage stability study of immobilized horseradish peroxidase showed retention of over 60% of initial activity after 20 days of storage at 4 °C and after 10 repeated catalytic cycles, indicating great practical application potential. By contrast, the free enzyme showed less than 20% of its initial activity after 20 days of storage and exhibited no recycling potential.

Development of a monoclonal antibody-based immunochromatographic assay for the detection of carbamazepine and carbamazepine-10, 11-epoxide.

In this study, haptens were designed to produce highly sensitive and specific monoclonal antibodies (mAb) against carbamazepine (CBZ) and its metabolite carbamazepine-10, 11-epoxide (CBZ-EP). According to the results of our competitive enzyme-linked immunosorbent assay (ic-ELISA), the half-maximum inhibitory concentration values for anti-CBZ and anti-CBZ-EP mAb were 0.18 and 0.59 ng/mL, respectively. An immunochromatographic assay (ICA) was developed for the determination of CBZ and CBZ-EP concentrations. This method can provide visible limits of detection ranging from 0.25 to 1 ng/mL, and cut-off limits ranging from 5 to 10 ng/mL, and takes 10 min to evaluate with the naked eye. Importantly, these observations were consistent with those obtained by ic-ELISA and liquid chromatography-mass spectrometry. The ICA assay represented a reliable, fast, and high-throughput method for the determination of CBZ and CBZ-EP in serum samples.

Paper-based molecularly imprinted-interpenetrating polymer network for on-spot collection and microextraction of dried blood spots for capillary electrophoresis determination of carbamazepine.

Carbamazepine is an antiepileptic drug with a narrow therapeutic index, which requires an efficient method for blood level monitoring. Finger-prick dried blood spot (DBS) collection is an alternative microsampling technique, which is less invasive than conventional venipuncture. Paper-based molecularly imprinted-interpenetrating polymer networks (MI-IPN) were developed as blood collection devices, which allowed for selective on-spot microextraction of carbamazepine from DBS. A hybrid of homogeneous polystyrene and silica gel polymer was synthesized and coated on a Whatman® Grade 1 filter paper. Proteins and other interferences in the blood samples were eliminated by using the MI-IPN collection devices, and the resulting DBS extracts were suitable for direct injection into the capillary electrophoretic instrument. The lower limit of quantitation of 4 µg/mL in capillary blood was achieved by the sweeping-micellar electrokinetic chromatography method using a KCl-containing matrix, which was sufficient for the therapeutic drug monitoring purposes. Method accuracies were in the range of 88.4 ± 4.5% to 94.5 ± 2.7% with RSD values ≤ 5.1%. The developed paper-based MI-IPN provided superior extraction efficiencies (92.2 ± 2.5%) in comparison with commercially available DBS collection cards, i.e., Whatman® 903 protein saver card (59.8 ± 2.8%) and GenCollect™ 2.0 card (47.2 ± 1.4%). The paper-based MI-IPN devices for DBS collection and on-spot extraction were characterized by simple fabrication, low costs, disposability, and reduction in sample preparation steps, and their further developments might open new perspectives in clinical applications, such as in therapeutic drug monitoring. Graphical abstract.

Ionic Liquid-Based Dispersive Liquidâ€"Liquid Microextraction for the Simultaneous Determination of Carbamazepine and Lamotrigine in Biological Samples.

This paper describes a new approach for the determination of carbamazepine and lamotrigine in biological samples by ionic liquid dispersive liquid-phase microextraction prior to high-performance liquid chromatography with ultraviolet detection. The effects of different ionic liquids (ILs) on the extraction efficiency of carbamazepine and lamotrigine were investigated. The highest extraction efficiencies of carbamazepine and lamotrigine were obtained using 30 ?L of 1-me-thyl-3-octylimidazolium hexafluorophosphate [C8MIM][PF6]. Several factors affecting the microextraction efficiency, such as the type and volume of extracting solvent, type and volume of disperser solvent, salt concentration, and pH of the sample solution have been optimized. The calibration plots were linear in the range of 0.1-20 mg L-1 for carbamazepine and 0.3-40 mg L-1 for lamotrigine with detection limits of 0.04 mg L-1 for carbamazepine and 0.07 mg L-1 for lamotrig-ine in plasma samples. The results confirm the suitability of the presented method as a sensitive method for the analysis of the target analytes in urine and plasma samples.

Removal of carbamazepine, diclofenac and trimethoprim by solar driven advanced oxidation processes in a compound triangular collector based reactor: A comparison between homogeneous and heterogeneous processes.

Contaminants of emerging concern (including pharmaceuticals) are not effectively removed by municipal wastewater treatment plants (WWTPs), so particular concern is related to agricultural wastewater reuse due to their possible uptake in crops irrigated with WWTPs effluents. Advanced oxidation processes (AOPs) and solar AOPs have been demonstrated to effectively remove pharmaceuticals from different aqueous matrices. In this study, an heterogeneous photocatalytic process using powdered nitrogen-doped TiO2 immobilized on polystyrene spheres (sunlight/N-TiO2) was compared to the benchmark homogenous AOP sunlight/H2O2 in a compound triangular collector reactor, to evaluate the degradation of three pharmaceuticals (carbamazepine (CBZ), diclofenac (DCF), trimethoprim (TMP)) in water. The degradation of the contaminants by sunlight and sunlight-AOPs well fit the pseudo-first order kinetic model (but for TMP under sunlight). High removal efficiency by solar photolysis was observed for DCF (up to 100%, half-life sunlight cumulative energy QS,1/2 = 2 kJ L-1, half-life time t1/2 = 32 min), while CBZ (32%, QS,1/2 = 28 kJ L-1, t1/2 = 385 min) and TMP (5% removal after 300 min) removal was poor. The degradation rate of CBZ, TMP and DCF was found to be slower during sunlight/H2O2 (QS,1/2 = 5 kJ L-1, t1/2 = 77 min; QS,1/2 = 20 kJ L-1, t1/2 = 128 min; QS,1/2 = 4 kJ L-1, t1/2 = 27 min, respectively) compared to sunlight/N-TiO2 (QS,1/2 = 4 kJ L-1, t1/2 = 55 min; QS,1/2 = 3 kJ L-1, t1/2 = 42 min; QS,1/2 = 2 kJ L-1, t1/2 = 25 min, respectively). These results are promising in terms of solar technology upscale because the faster degradation kinetics observed for sunlight/N-TiO2 process would result in smaller treatment volume, thus possibly perspective compensating the cost of the photocatalyst.

Validation of a liquid chromatography coupled with tandem mass spectrometry method for the determination of drugs in wastewater using a three-phase solvent system.

Pharmaceuticals constitute one of the most important emerging classes of environmental pollutants. A three-phase solvent system of water, water containing 0.1% of formic acid and acetonitrile was successfully used to separate, by liquid chromatography with mass spectrometry (LC-MS), polarity-matched pharmaceuticals, that is, carbamazepine, clarithromycin, and erythromycin, as well as amoxicillin and metformin. Despite of polarity similarities, these pharmaceuticals were completely resolved in the analytical run time of 15 min. The optimized three-phase solvent system based-method was validated for the simultaneous analysis of six matched-polarity pharmaceuticals in wastewater samples. Good linearity (coefficient of determination more than 0.993) and precision (relative standard deviation less than 15.66%) were achieved. Recovery of analytes from the wastewater was between 0.70 and 1.18. Limits of detections ranged from 0.0001 to 0.5114 µg/L. No significant matrix effect, evaluated by post extraction addition, was observed in the electrospray ionization (ESI) source. Then, this methodology has been successfully applied to environmental study of pharmaceutical residues occurring in influent and effluent wastewater samples, from the main wastewater treatment plant in Potenza (Basilicata, Southern Italy).

Construction of carbon-doped supramolecule-based g-C3N4/TiO2 composites for removal of diclofenac and carbamazepine: A comparative study of operating parameters, mechanisms, degradation pathways.

An eco-friendly 2D heterojunction photocatalyst composites (BCCNT) consisting of carbon-doped supramolecule-based g-C3N4 (BCCN) layers and TiO2 nanoparticles has been fabricated via an in-situ method. Based on the SEM and XPS results affirmed that the coaction of doped carbon and supramolecule precursors lead to the different morphology of pure g-C3N4, C-doped g-C3N4 have improved the photodegradation diclofenac (DCF) and carbamazepine (CBZ). And the degradation efficiencies of DCF and CBZ could reach 98.92% and 99.77%, which were separately corresponded to 30 min (min) and 6 h (h) of LED lamp illumination. Additionally, the effects of catalysis dosage, solution pH, natural organic matter (NOM), inorganic anions (Cl-, SO42-, NO3-) and different water matrices were deeply investigated. The scavenger experiments demonstrated that •O2-, h+ were main active species under visible irradiation. Furthermore, the photodegradation pathways of DCF and CBZ were detected by high-resolution mass spectrometry (HRMS) instruments and three-dimensional excitation-emission matrix fluorescence spectra (3D EEMs). Eventually, the possible photocatalytic mechanisms of BCCNT were proposed.

Efficiency comparison of nylon-6-based solid-phase and stir bar sorptive extractors for carbamazepine extraction.

Aim: Two approaches based on molecularly imprinted polymers-stir bar sorptive extraction (MIP-SBSE) and -magnetic solid-phase extraction (MIP-MSPE) have been used for extraction of carbamazepine (CBZ) from serum samples. Methodology: In MSPE and SBSE, development was achieved by employing a polycaprolactam coating. The Cecil® chromatographic system equipped with a UV-Vis detector was used for analytical determination of CBZ. Results: The linearity of calibration curves was in the concentration ranges of 0.2-12 and 0.05-12 µg ml-1 for MIP-SBSE and MIP-MSPE, respectively. Conclusion: MIP-MSPE was selected in preference to MIP-SBSE since lower limits of detection were achievable using MIP-MSPE method. The CBZ-MIP-MSPE-HPLC-UV method was successfully applied to CBZ determination in real serum samples of patients receiving CBZ.

The relative importance of different carbon structures in biochars to carbamazepine and bisphenol A sorption.

Biochar, a carbon-rich material, has attracted immense attention owing to its applications in soil remediation. However, the mechanisms by which heterogeneous carbon structures of biochars immobilize organic contaminants are not yet fully understood. In this study, the noncondensed aromatic components in biochars were selectively removed through bleaching. Different techniques, such as 13C nuclear magnetic resonance, were applied to characterize the biochar compositions, and thus the role of the different carbon structures in organic contaminant sorption was discussed. The aromatic carbon structures in biochars were gradually developed and evolved from noncondensed to condensed structure with increasing pyrolytic temperatures from 300 to 700 °C. Based on elemental analysis, the carbon removed by bleaching decreased from 43.9% to 5.92% with increasing temperatures. After the surface area normalization of the apparent sorption, bleaching increased the sorption of carbamazepine and bisphenol A on biochars produced at 500 °C, but not for those produced at 300 and 700 °C. Bleaching removed noncondensed aromatics and enriched condensed aromatics, which resulted in increased sorption. However, bleaching also resulted in the blockage of micropores in biochars with abundant condensed aromatics, causing decreased sorption. The apparent sorption was determined by the balancing of these two opposite effects.

Development and application of water-compatible molecularly imprinted polymers for the selective extraction of carbamazepine from environmental waters.

A molecularly imprinted polymer (MIP) was designed in order to allow the selective solid-phase extraction of carbamazepine (CBZ), an anticonvulsant and mood-stabilizing drug, at ultra-trace level from aqueous environmental samples. A structural analog of CBZ was selected as a dummy template and different synthesis conditions were screened. The selectivity of the resulting imprinted polymers was evaluated by studying the retention of CBZ in a solvent similar to the one used for the synthesis. The presence of imprinted cavities in the polymers was then demonstrated by comparing the elution profiles (obtained by using MIP and a non-imprinted polymer, NIP, as a control) of the template, of CBZ, and of a structural analog of CBZ. Then, the extraction procedure was further optimized for the treatment of aqueous samples on the two most promising MIPs, with special attention being paid to the volume and composition of the percolation and washing solutions. The best MIP provided a highly selective retention in tap water with 81% extraction recovery for CBZ in the elution fraction of the MIP and only 14% for NIP. The repeatability of the extraction procedure was demonstrated for both tap and river waters (RSD below 4% in river water) for the drugs CBZ, oxcarbamazepine, and one metabolite (carbamazepine 10,11-epoxide). A MIP capacity of 1.15 µmol g-1 was determined. Finally, an analytical procedure involving the MIP was developed allowing the detection of CBZ at a concentration level of only a few nanograms per liter in river water. The selectivity provided by the MIP resulted in a 3000-fold increase of the signal-to-noise ratio in LC/MS analysis as compared to the use of conventional sorbent. Graphical abstract.

Solid-phase extraction of drugs with cuttlefish bone powder as a sorbent.

We investigated cuttlefish bone powder for the solid-phase extraction of naproxen, ibuprofen, and carbamazepine. The basic principles controlling the extraction are presented to aid in the choice of the nature and quantity of the extracting phase according to the sample matrix and the solute properties, based on the mechanisms of phase retention. Their retention mechanism is based on hydrogen bonding and electrostatic interactions. The results show a significant recovery rate for the three drugs, selectivity, and low cost. The method has successfully reduced the amount of tested pharmaceuticals with recoveries >87% at pH 4.

A four-year simulation of soil aquifer treatment using columns filled with San Gabriel Valley sand.

Two column pairs filled with 3.05-m of a sandy soil from the Upper San Gabriel Valley were operated for a period of four and ½ years on municipal effluent from the San Jose Creek Water Reclamation Plant operated by the Sanitation Districts of Los Angeles County (LACSD). One column pair was fed filtered, chlorinated effluent (tertiary effluent) for the entire period. The other pair was fed ozonated secondary effluent for 8-mo, ozonated secondary effluent filtered through biological activated carbon (O3/BAC) for 7-mo and tertiary effluent for 38-mo. Each column pair was operated in series, where the first column was operated for a shorter residence time and the second column for a longer residence time. Residence times tested were 5-d, 28-d, 30-d, 58-d, 60-d, 150-d and 180-d. For the last 38-mo, both pairs of columns had a residence time of 30-d in the first column and the total residence time of the two pairs was 150 and 180-d, respectively. Testing showed both of these pairs had the same long-term performance. The column pairs with a 150 to 180-d residence time, which were both fed tertiary effluent, reached an effluent total organic carbon (TOC) of 1.8 mg/L. Column pairs with a 28 to 30-d residence time, which were fed tertiary, ozonated, and O3/BAC effluent, reached effluent TOCs of 2.3, 2.1 and 1.8 mg/L respectively. In the latter, some TOC removal was shifted from the soil columns to the BAC. During the last 38 months of testing, using tertiary effluent as the source water, a series of sampling events was performed throughout the soil column system for N-nitrosodimethylamine (NDMA) and chemicals of emerging concern (CECs). NDMA was substantially reduced in all the columns, with a median value of 3 ng/L after 30-d and <2 ng/L after both 150 and 180-d. Twenty-one CECs were found in the majority of tertiary effluent samples, twelve of which were attenuated by the soil columns and the remaining were not. Chemicals found to be recalcitrant were 4-nonylphenol, acesulfame-k, carbamazepine, lidocaine, primidone, simazine, sucralose, sulfamethoxazole, and TCEP. Using excitation-emission matrix (EEM) techniques, soluble microbial products (SMP) peak characteristic of effluent organic matter (EfOM) is nearly eliminated after a 30-d hydraulic retention time (HRT) and completely eliminated in the 150/180-d samples. The intensity of the other peaks is significantly reduced as well, resulting in an EEM much like that of natural groundwater.

Degradation and intermediates of diclofenac as instructive example for decomposition of recalcitrant pharmaceuticals by hydroxyl radicals generated with pulsed corona plasma in water.

Seven recalcitrant pharmaceutical residues (diclofenac, 17α-ethinylestradiol, carbamazepine, ibuprofen, trimethoprim, diazepam, diatrizoate) were decomposed by pulsed corona plasma generated directly in water. The detailed degradation pathway was investigated for diclofenac and 21 intermediates could be identified in the degradation cascade. Hydroxyl radicals have been found primarily responsible for decomposition steps. By spin trap enhanced electron paramagnetic resonance spectroscopy (EPR), OH-adducts and superoxide anion radical adducts were detected and could be distinguished applying BMPO as a spin trap. The increase of concentrations of adducts follows qualitatively the increase of hydrogen peroxide concentrations. Hydrogen peroxide is eventually consumed in Fenton-like processes but the concentration is continuously increasing to about 2mM for a plasma treatment of 70min. Degradation of diclofenac is inversely following hydrogen peroxide concentrations. No qualitative differences between byproducts formed during plasma treatment or due to degradation via Fenton-induced processes were observed. Findings on degradation kinetics of diclofenac provide an instructive understanding of decomposition rates for recalcitrant pharmaceuticals with respect to their chemical structure. Accordingly, conclusions can be drawn for further development and a first risk assessment of the method which can also be applied towards other AOPs that rely on the generation of hydroxyl radicals.

Simultaneous extraction and concentration of water pollution tracers using ionic-liquid-based systems.

Human activities are responsible for the release of innumerous substances into the aquatic environment. Some of these substances can be used as pollution tracers to identify contamination sources and to prioritize monitoring and remediation actions. Thus, their identification and quantification are of high priority. However, due to their presence in complex matrices and at significantly low concentrations, a pre-treatment/concentration step is always required. As an alternative to the currently used pre-treatment methods, mainly based on solid-phase extractions, aqueous biphasic systems (ABS) composed of ionic liquids (ILs) and K3C6H5O7 are here proposed for the simultaneous extraction and concentration of mixtures of two important pollution tracers, caffeine (CAF) and carbamazepine (CBZ). An initial screening of the IL chemical structure was carried out, with extraction efficiencies of both tracers to the IL-rich phase ranging between 95 and 100%, obtained in a single-step. These systems were then optimized in order to simultaneously concentrate CAF and CBZ from water samples followed by HPLC-UV analysis, for which no interferences of the ABS phase-forming components and other interferents present in a wastewater effluent sample have been found. Based on the saturation solubility data of both pollution tracers in the IL-rich phase, the maximum estimated concentration factors of CAF and CBZ are 28595- and 8259-fold. IL-based ABS can be thus envisioned as effective pre-treatment techniques of environmentally-related aqueous samples for a more accurate monitoring of mixtures of pollution tracers.

Ecotoxicological efficiency of advanced ozonation processes with TiO2 and black light used in the degradation of carbamazepine.

The aim of the present study was to evaluate the ecotoxicological efficiency of two advanced ozonation processes (AOzPs), the catalytic ozonation (O3/TiO2) and the photocatalytic ozonation (O3/TiO2/black light), in the remotion of carbamazepine. The ecotoxicological efficiency was assessed through the use of lethal and sublethal assays with species Vibrio fischeri and Daphnia magna. Results demonstrated that the AOzPs presented an efficiency of carbamazepine removal higher than 99% (carbamazepine < 2 µg/L) after 12 min of treatment. Relatively to ecotoxicological evaluation, application of acute assay to V. fischeri and chronic assay to D. magna allowed us to highlight that these technologies may form some transformation products that induce toxicity in the bacteria and the crustacean, once these organisms exposed to the undiluted solutions (100%) showed a decrease in the bioluminescence (vibrio) and end up dying before and during the first reproduction (daphnia). Despite that, when the chronic results obtained with the diluted solutions (50 and 25%; important to assess a more realistic scenario considering the dilution factor at the environment) were analyzed, no mortality at the mothers was observed. Compared to a carbamazepine solution (200 µg/L), diluted solutions improved of the reproduction parameters, and no toxic effects in the juvenoid system and in the embryonic development were observed. Relatively to the ecdysteroid effect of a carbamazepine solution (200 µg/L), only the photocatalytic ozonation treatment was able to remove the action of the drug. These results highlight the importance of complementing chemical analysis with ecotoxicological bioassays to assess the best technology to improve the surface water and effluent quality.

Application of cation-modified sulfur nanoparticles as an efficient sorbent for separation and preconcentration of carbamazepine in biological and pharmaceutical samples prior to its determination by high-performance liquid chromatography.

A simple and rapid solid phase extraction procedure using a mini-column packed with modified sulfur nanoparticles as a new, efficient and reusable sorbent has been developed for the preconcentration of carbamazepine prior to its determination by high performance liquid chromatography. This method is based on the retention of carbamazepine by modified sulfur nanoparticles which are quite efficient for fast adsorption and desorption of carbamazepine. An HPLC system including C18, 250×4.6mm column, methanol-acidic water (pH=2.6 by acetic acid) (60:40) as mobile phase and UV detector (λ=276nm) was used. The effects of multiple experimental conditions such as the effect of pH, type and volume of buffer, type and volume of eluent, sample and eluent flow rate, sorbent amount and interfering ions, on the analytical performance of the method were investigated. The calibration curve was linear in the range of 0.5-200ngmL-1 and LOD of the proposed method was found to be 0.16ngmL-1. The procedure was successfully applied for the determination of carbamazepine in pharmaceutical samples, human plasma and breast milk.

Ozonation as a pretreatment process for nanofiltration brines: Monitoring of transformation products and toxicity evaluation.

Considerable interest has been given to using nanofiltration (NF) in lieu of reverse osmosis for water reclamation schemes due to lower energy consumption, higher flux rates while ensuring good micropollutants rejection. The application NF results in the generation of a large concentrated waste stream. Treatment of the concentrate is a major hurdle for the implementation of membrane technologies since the concentrate is usually unusable due to a large pollutants content. This work focuses on the application of ozonation as pretreatment of urban NF concentrates, the generation of transformation products and their relative toxicity. Three pharmaceutical micropollutants largely encountered in water cycle were selected as target molecules: acetaminophen, carbamazepine and atenolol. Through accurate-mass Q-TOF LC-MS/MS analyses, more than twenty ozonation products were detected, structure proposals and formation pathways were elaborated. Attempts were made to understand the correlation between the transformation products and acute toxicity on Vibrio fischeri strain. It is the first time that an integrated study reported on the ozonation of pharmaceuticals in urban membrane concentrates, in terms of transformation products, kinetics, degradation mechanisms, as well as toxicity assessment.