Concentrations Of Diclofenac Research Articles

Diclofenac removal from the wastewater using activated sludge and analysis of multidrug resistant bacteria from the sludge

Diclofenac is an anti-inflammatory drug and has been frequently detected from the wastewater. In the present study, factors affecting diclofenac adsorption on sewage sludge was evaluated. At 1 mg/L initial diclofenac concentration, more than 80% diclofenac removal was achieved. Adsorption increased at higher concentration (100 mg/L concentration) and more than 99% diclofenac was adsorbed from the wastewater. Significant removal of diclofenac was observed after 5 min contact time. The adsorption efficacy was more than 98% after 50 and 60 min. Pseudo-first and second order kinetics revealed reasonable regression value (0.9) indicated that the model is best fitted. Diclofenac adsorption was extremely high at acidic pHs than alkaline range. The sludge samples showed the presence of multi drug resistant bacteria. Vancomycin-resistant enterococcus stains were 27%, Methicillin-resistant Staphylococcus aureus positive strains were 16.5% and Extended-spectrum betal-lactamase-harbouring Enterobacteriacea were 65.4% in the sludge. The drug resistance Enterobacteriaceae revealed 14 Klebsiella pneumonia strains, 11 strains from E. coli and two from the genus Enterobacter. To conclude, the activated sludge could be effectively utilized for the removal of diclofenac from wastewater.

Hydroxylamine enhanced Cu(II)/peroxydisulfate system for diclofenac degradation: Efficiency, influence factors and mechanism

In this work, diclofenac (DCF), a nonsteroidal anti-inflammatory drug, was effectively removed in Cu(Ⅱ)/hydroxylamine (HAm)/peroxydisulfate (PDS) system in neutral condition. It was proved that the introduction of HAm significantly enhanced DCF degradation in Cu(Ⅱ)/PDS system by accelerating Cu(Ι)/Cu(Ⅱ) cycle. According to the results of electron paramagnetic resonance (EPR) and scavenging experiments, the contribution of SO4•- and •OH to DCF degradation in Cu(Ⅱ)/HAm/PDS system was comparable at pH 7. The effects of operational parameters including initial pH, Cu(Ⅱ) dose, HAm concentration, PDS concentration and initial DCF concentration on the removal of DCF were systematically investigated, and the influence of water matrix components (i.e., SO42-, NO3-, Cl-, HCO3- and natural organic matter) on DCF degradation were also studied. Five degradation products were detected using UPLC-Q-TOF-MS, and four degradation pathways were thereby proposed including hydroxylation, dehydrogenation, dehydration and decarboxylation. The mineralization of DCF in Cu(Ⅱ)/HAm/PDS system was limited according to the result of total organic carbon (TOC) test. Various emerging contaminants were also effectively degraded in Cu(Ⅱ)/HAm/PDS system, suggesting the applicability of this system in degradation of other refractory organic contaminants. This study provides a method to enhance the treatment efficiency of Cu(Ⅱ)/PDS system and an effective way to degrade emerging contaminants at mild condition.

Zebrafish Oatp1d1 Acts as a Cellular Efflux Transporter of the Anionic Herbicide Bromoxynil.

Toxicokinetics (TK) of ionic compounds in the toxico-/pharmacological model zebrafish embryo (Danio rerio) depend on absorption, distribution, metabolism, and elimination (ADME) processes. Previous research indicated involvement of transport proteins in the TK of the anionic pesticide bromoxynil in zebrafish embryos. We here explored the interaction of bromoxynil with the organic anion-transporting polypeptide zebrafish Oatp1d1. Mass spectrometry imaging revealed accumulation of bromoxynil in the gastrointestinal tract of zebrafish embryos, a tissue known to express Oatp1d1. In contrast to the Oatp1d1 reference substrate bromosulfophthalein (BSP), which is actively taken up by transfected HEK293 cells overexpressing zebrafish Oatp1d1, those cells accumulated less bromoxynil than empty vector-transfected control cells. This indicates cellular efflux of bromoxynil by Oatp1d1. This was also seen for diclofenac but not for carbamazepine, examined for comparison. Correspondingly, internal concentrations of bromoxynil and diclofenac in the zebrafish embryo were increased when coexposed with BSP, inhibiting the activities of various transporter proteins, including Oatp1d1. The effect of BSP on accumulation of bromoxynil and diclofenac was enhanced in further advanced embryo stages, indicating increased efflux activity in those stages. An action of Oatp1d1 as an efflux transporter of ionic environmental compounds in zebrafish embryos should be considered in future TK assessments.

Assessment of Diclofenac Adsorption into Activated Sludge: Mechanism and Thermodynamic

This study aimed at understanding and characterizing the sorption process of Diclofenac (DCF) onto activated sludge under conditions similar to those of a conventional Wastewater Treatment Plant (WWTP). Two experiments were performed: kinetics test, composed of six identical pairs of control/sample with the same DCF concentration stirred under constant rotation for different intervals; and an adsorption thermodynamics test with one pair of control samples and six duplicate samples with DCF concentrations from 5 - 100 mg L-1 stirred under constant rotation for the same period. DCF concentrations in the supernatant were measured in time spectrophotometrically at 282 nm. The adsorption of diclofenac onto the activated sludge reached its equilibrium after approximately 2 hours. The results showed that the process was best described by the Freundlich and Langmuir isotherm models, which suggest that the adsorption of DCF onto the activated sludge is a non-favorable second order reaction with a monolayer coverage. The Temkin isotherm model suggests that the heat of adsorption of the DCF molecules in the layer decreases linearly as a result of the increased surface coverage and follows a chemisorption mechanism. The amount of DCF adsorbed onto the sludge particles varied between 17 and 44%, with the adsorption ratio of DCF per gram of sludge being considerably low (< 1 mg per g of sludge). This might be a result of the longer hydraulic retention times (HRT) adopted, considering that DCF may be toxic to the sludge microbiota, interfering with DCF removal from the supernatant. Thus, improving diclofenac removal by aerobic WWTP might require an adjustment of HRT to enhance sorption onto the sludge and reduce its impact on bacterial community.

Microwave-assisted synthesis of RuTe2/black TiO2 photocatalyst for enhanced diclofenac degradation: Performance, mechanistic investigation and intermediates analysis

• The crystallized RuTe 2 acted as a cocatalyst for photocatalysis was reported for the first time. • 0.5% RuTe 2 /B-TiO 2 achieved 95.2% DCF degradation efficiency, which was 1.2 times higher than that of pure B-TiO 2 . • The intermediates for the photodegradation of DCF were detected and removal pathways was rationalized. Seeking active and low-cost cocatalysts is a vital task for solving the sluggish kinetics of photocatalysis process in environmental management. Herein, we report a novel and high-efficiency crystallized RuTe 2 cocatalyst, and loaded it onto black TiO 2 to form photocatalytic heterostructure (denoted as RuTe 2 /B-TiO 2 ) for diclofenac (DCF) degradation. To the best of our knowledge, the RuTe 2 as a cocatalyst for photocatalysis based on swift electron capture has not been documented yet. The degradation efficiency of DCF over 0.5% RuTe 2 /B-TiO 2 reached 95.2% for 120 min, which is 1.2 times higher than that of pure B-TiO 2 . In addition, the effects of different calcination temperatures, catalyst amounts, DCF concentrations and solution pH of the as-prepared catalysts were also investigated in depth. Spectroscopy/electrochemistry showed that 0.5% RuTe 2 /B-TiO 2 exhibited a narrower band gap, more active sites and better electrical conductivity than pure B-TiO 2 . Experiments with trapping agents have shown that O 2 – was the main active substance under irradiation. Furthermore, intermediates for the photodegradation of DCF were detected by liquid chromatography mass system (LC-MS) and density functional theory (DFT) calculations. Finally, the degradation pathway was rationalized and a possible photocatalytic mechanism for 0.5% RuTe 2 /B-TiO 2 was proposed.

Effects of Diclofenac on the Oxidative Stress Parameters of Freshwater Fish Oreochromis niloticus

The indiscriminate use and abuse of pharmaceuticals have led to pharmaceutical residues in the aquatic environment which has been receiving great attention since significant levels of contamination have been found. The present study investigated the acute and sub-lethal effects of a pharmaceutical drug diclofenac on oxidative stress parameters and the recovery ability in O. niloticus. The juveniles were exposed to different concentrations of diclofenac to determine the 96 h LC50. The results indicated that diclofenac was toxic to O. niloticus with a 96 h LC50 of 0.489mg/L. The percentage mortality increased as the concentrations increased. Fish were exposed to a control (0.00 mg/L) and three sub-lethal concentrations of 0.48, 0.32, and 0.25 mg/L of diclofenac for 28 days and allowed to recover for 7 days. The result of the sub-lethal test indicated that the responses were dose and duration dependent. The oxidative stress results showed significant concentration- and time-dependent increases in the values of lipid peroxidation, glutathione peroxidase, glutathione reductase and reduced glutathione but reduction in catalase and superoxide dismutase in the liver of the exposed fish. Many of the oxidative parameters were found to be restored after the 7-day recovery period. These results showed that diclofenac exposure had a profound negative influence on the selected indices of O. niloticus.

Electrochemical Method for Ease Determination of Sodium Diclofenac Trace Levels in Water Using Graphene-Multi-Walled Carbon Nanotubes Paste Electrode.

Sodium diclofenac (DCF) presence reported in water use cycle at various concentrations including trace levels necessitates continuous development of advanced analytical method for its determination. In this work, ease electrochemical methods for DCF determination based on voltammetric and amperometric techniques were proposed using a simple combination of graphene with multi-walled carbon nanotubes as paste electrode. Integration of the graphene with multi-walled carbon nanotubes enlarged the electroactive surface area of the electrode and implicitly enhanced the electrochemical response for DCF determination. On the basis of the sorption autocatalytic effect manifested at low concentration of DCF, we found that the preconcentration step applied prior to differential-pulsed voltammetry (DPV) and multiple-pulsed amperometry (MPA) allowed for the enhancement of the electroanalytical performance of the DCF electrochemical detections, which were validated by testing in tap water. The lowest limit of detection (LOD) of 1.40 ng·L−1 was found using preconcentration prior to DPV under optimized operating conditions, which is better than that reached by other carbon-based electrodes reported in the literature.

Artificial neural network and response surface methodology modeling for diclofenac removal by quaternized mesoporous silica SBA-15 in aqueous solutions

Diclofenac (DCF) is a non-steroidal, anti-inflammatory drug commonly prescribed for humans and animals. DCF has been widely detected in aquatic environments and wastewater, and so various adsorbents have been applied for DCF removal from aqueous solutions. Here, we explored DCF removal by quaternary ammonium-functionalized mesoporous silica SBA-15 (q-SBA-15) in aqueous solutions using artificial neural network (ANN) and response surface methodology (RSM) modeling. For this purpose, SBA-15 was synthesized and quaternized with dimethyloctyl[3-(trimethoxysilyl)propyl] ammonium chloride to obtain q-SBA-15. The physicochemical characteristics of q-SBA-15 were examined using various instruments including field emission scanning electron microscopy, transmission electron microscopy, elemental analysis, nitrogen gas adsorption-desorption analysis, nuclear magnetic resonance spectroscopy, X-ray diffractometry, Fourier-transform infrared spectrometry (FTIR), and X-ray photoelectron spectrometry (XPS). N2 adsorption-desorption analysis indicated that q-SBA-15 had a BET surface area of 125.1 m2/g, an average pore diameter of 3.86 nm, and a mesopore volume of 0.121 cm3/g. In the FTIR spectra, several new peaks appeared after DCF removal, confirming DCF adsorption onto the surface of q-SBA-15. The XPS spectra illustrated that DCF was adsorbed onto N+ surface sites on the quaternary ammonium moiety of q-SBA-15 through anion exchange between anionic DCF− and chloride ion. Single-parameter experiments were conducted in terms of initial pH, adsorbent dosage, reaction time, and initial DCF concentration. DCF removal rate decreased gradually in the initial pH of 6.0–10.0. DCF removal reached equilibrium at 12 h with the maximum removal capacity of 593 mg/g. Multi-parameter experiments were designed using the central composite design method with four input parameters and two output parameters (DCF removal rate and final pH). Fifty-six experiments (28 experimental conditions in duplicate) were conducted to examine the simultaneous effects of the input parameters on the output parameters. Based on the experimental data, RSM and ANN models were developed to predict the DCF removal rate and final pH. The additional experimental data (4 experimental conditions in duplicate) demonstrated that the developed ANN model had better predictability than the RSM model for the output parameters.

Long-term exposure to environmental diclofenac concentrations impairs growth and induces molecular changes in Lymnaea stagnalis freshwater snails

As pharmaceutical substances are highly used in human and veterinary medicine and subsequently released in the environment, they represent emerging contaminants in the aquatic compartment. Diclofenac (DCF) is one of the most commonly detected pharmaceuticals in water and little research has been focused on its long-term effects on freshwater invertebrates. In this study, we assessed the chronic impacts of DCF on the freshwater gastropod Lymnaea stagnalis using life history, behavioral and molecular approaches. These organisms were exposed from the embryo to the adult stage to three environmentally relevant DCF concentrations (0.1, 2 and 10 μg/L). The results indicated that DCF impaired shell growth and feeding behavior at the juvenile stage, yet no impacts on hatching, locomotion and response to light stress were noted. The molecular findings (metabolomics and transcriptomic) suggested that DCF may disturb the immune system, energy metabolism, osmoregulation and redox balance. In addition, prostaglandin synthesis could potentially be inhibited by DCF exposure. The molecular findings revealed signs of reproduction impairment but this trend was not confirmed by the physiological tests. Combined omics tools provided complementary information and enabled us to gain further insight into DCF effects in freshwater organisms.

Decomposition of diclofenac in sewage from municipal wastewater treatment plant using ionizing radiation

Abstract The decomposition of diclofenac (DCF) in sewage sludge from municipal wastewater treatment plant was investigated. It was found that adsorption of DCF on sludge is about 40%. Compared to previous studies, where the degradation yield in aqueous solution was 100%, in those experiments at the dose up to 5 kGy, only 50% of initial DCF concentration of 50 mg L−1 was decomposed in sediment and in solution over the sediment. The experiments were carried out using both gamma radiation and electron beam. It has been observed that DCF in the aqueous phase, above the sediment, was decomposed with the same efficiency using both gamma radiation and electron beam. Whereas for DCF in the sediment, a higher degradation efficiency was found when gamma radiation was applied. This is most likely due to the limited penetration depth of the electron beam into the sludge layer. It was shown that the applied peroxide addition (in a stoichiometric amount needed for complete mineralization of 50 mg L−1 DCF) did not cause increase in yield of DCF decomposition.

Towards real-time release of pharmaceutical tablets: 100% in-line control via near-infrared spatially resolved spectroscopy and 3D microwave resonance technology

In the scope of 100% in-line quality control and real-time release of pharmaceutical tablets, the authors present a flexible inspection module for in-line tablet analysis with integrated multipoint near-infrared (NIR) spectroscopy and 3D microwave resonance technology (3D MRT). Via an industrial case study on Diclofenac Sodium tablets, the abilities of this versatile process analytical technology (PAT) tool are presented. It is demonstrated that the combination of Diclofenac concentration prediction via NIR spectroscopy and mass prediction via 3D MRT allow to estimate the dosage of each individual tablet. Single sample repetition tests were performed on 5 tablets, measured 10 times on three different days. A high accuracy and precision of prediction was shown, with an average standard deviation below 0.5 mg. The inspection run demonstrated the added value of such inspection and sorting strategies based on the calculated dosage of individual tablets.

Biochemical and respiratory parameters in a gastropod Radix balthica exposed to diclofenac

Diclofenac, an anti-inflammatory drug, is often detected in natural waters in the ng/L to μg/L range, posing a threat to aquatic organisms. The study focused on the effects of diclofenac in a gastropod mollusk Radix balthica. A 72-h exposure to environmentally relevant concentrations of diclofenac caused deviations from the baseline activities of the studied enzymes in the digestive gland of snails. Acetylcholinesterase activity was induced by the end of exposure, with the most pronounced increase at 3 μg/L. Results on glutathione-S-transferase activity were nonuniform, and no significant variations were observed in thiobarbituric acid reactive substances concentrations, indicating that diclofenac did not cause oxidative stress in the digestive gland of R. balthica at 0.04–4 μg/L range. Diclofenac lowered the oxygen consumption rate in snails in a concentration-dependent manner. At concentrations ≥0.9 μg/L, animals attempted to switch aquatic respiration to breathing air to regulate their metabolic needs. The study showed that diclofenac at environmentally relevant concentrations affected the fitness of R. balthica.

Analysis of adsorption characteristics of diclofenac to sucrose-derived carbon spheres from aqueous solutions

Diclofenac (DCF) is a nonsteroidal anti-inflammatory drug commonly found in wastewater and drinking water. The potential of carbon spheres (CSs) to serve as adsorbents in removal of DCF from water has been explored recently. However, glucose-derived CSs and cellulose-derived CSs reportedly have very low DCF adsorption capacities. Here, we describe the synthesis of sucrose-derived carbon spheres (SDCSs) for adsorption of DCF from aqueous solutions. The physicochemical properties of the SDCSs were characterized using various instrumental techniques. The SDCSs were spherical particles with an average size of 224.2 ± 19.5 nm, a point of zero charge (pHpzc) of 3.14, a Brunauer–Emmett–Teller specific surface area of 239.3 m2/g, a total pore volume of 0.142 cm3/g, and an average pore diameter of 2.38 nm. The adsorption characteristics of the SDCSs were investigated under batch conditions by varying the solution pH, reaction time, initial DCF concentration, and temperature. Adsorption experiments demonstrated that the DCF adsorption capacity was highest at an initial pH of 5 and decreased gradually as the pH was increased to 11. X-ray photoelectron spectroscopy spectra of the SDCSs before and after DCF adsorption indicate that DCF adsorption to the SDCSs occurred through hydrogen-bond formation and π-π interactions. According to the pHpzc value and experimental pH data, repulsive electrostatic interactions between the negatively charged SDCSs and negatively charged DCF resulted in a decrease of DCF adsorption capacity as pH increased. Kinetic and equilibrium data showed that DCF adsorption to the SDCSs reached equilibrium at 6 h, with a maximum adsorption capacity of 531.5 mg/g, which was far higher than glucose-derived CSs and cellulose-derived CSs. DCF adsorption to the SDCSs was endothermic, increasing with increasing temperature from 10 ℃ to 40 ℃. Five adsorption-desorption cycles demonstrated that the SDCSs can be regenerated with methanol and reused in DCF adsorption. This study demonstrates that SDCSs have a high adsorption capacity and reusability for adsorption of DCF from aqueous solutions.

Spatiotemporal trends and annual fluxes of pharmaceuticals in a Scottish priority catchment

Pharmaceuticals (a class of emerging contaminants) are continuously introduced into effluent-receiving surface waters due to their incomplete removal within wastewater treatment plants (WWTPs). This work investigated the presence and distribution of eight commonly used human pharmaceuticals in the River Dee (Scotland, UK), a Scottish Environment Protection Agency priority catchment that is a conservation site and important raw water source. Grab sampling and passive sampling (Polar Organic Chemical Integrative Sampler, POCIS) was performed over 12 months, targeting: paracetamol, ibuprofen, and diclofenac (analgesics/anti-inflammatories); clarithromycin and trimethoprim (antibiotics); carbamazepine and fluoxetine (psychoactive drugs); and 17α-ethynylestradiol (estrogen hormone). Sampling sites spanned from the river's rural source to the heavily urbanised estuary into the North Sea. Ibuprofen (ranging 0.8–697 ng/L), paracetamol (ranging 4–658 ng/L), trimethoprim (ranging 3–505 ng/L), diclofenac (ranging 2–324 ng/L) and carbamazepine (ranging 1–222 ng/L) were consistently detected at the highest concentrations through grab sampling, with concentrations generally increasing down river with increasing urbanisation. However, POCIS revealed trace contamination of most compounds throughout the river (commonly <0.5 ng/L), indicating pollution may be related to diffuse sources. Analysis of river flows revealed that low flow and warm seasons corresponded to statistically significantly higher concentrations of diclofenac and carbamazepine, two compounds of environmental and regulatory concern. Below the largest WWTP, annual average fluxes ranged 0.1 kg/yr (clarithromycin) to 143.8 kg/yr (paracetamol), with 226.2 kg/yr for total target compounds. It was estimated that this source contributed >70% of the total mass loads (dissolved phase) of the target compounds in the river. As the River Dee is an important raw water source and conservation site, additional catchment monitoring is warranted to safeguard water quality and assess environmental risk of emerging contaminants, particularly in relation to unusual weather patterns, climate change and population growth.

Applicability of osmotic bioreactor using potassium pyrophosphate as draw solution combined with reverse osmosis for removal of pharmaceuticals and production of high quality reused water

Osmotic membrane bioreactor (OMBR) has emerged as an alternative to the conventional membrane bioreactor (MBR) to precede reverse osmosis (RO) for wastewater treatment and reuse. However, it has not been fully demonstrated yet that technical improvements that may be obtained by OMBR-RO, when compared to MBR-RO, will be sufficient to support its application beyond laboratory scale. Therefore, this work addressed some key challenges to provide a general evaluation of the applicability of OMBR-RO for water reuse, focusing on the analysis of the combined process. Potassium pyrophosphate (K4P2O7) proved to be a promising draw solute to mitigate the prevalent problem of high reverse salt flux in OMBR, as the solute permeability obtained (0.05 LMH) is lower than those previously reported in literature using sodium chloride. The use of OMBR before RO allowed maintaining constant RO permeate flux. In terms of reused water quality (i.e. RO permeate), OMBR-RO process provided water of better quality: the concentrations of nitrite, nitrate, sulfamethoxazole, carbamazepine and diclofenac were 4, 10, 74, 6 and 4 times lower, respectively, in this process when compared to an MBR-RO. The only exception as 17-α-ethinylestradiol, whose concentration was higher in reused water obtained by OMBR-RO. The improvement in water quality for almost all PhACs and operational advantages due to double membrane barrier can support OMBR-RO implementation, particularly when very high removal of PhACs and nutrients is critical for the reuse option.

Ozonation of diclofenac in a laboratory scale bubble column: Intermediates, mechanism, and mass transfer study

Diclofenac (DCF), a non-steroidal analgesic drug, has been recurrently detected in surface and groundwater during the past two decades. Traces of DCF pass through the conventional wastewater treatment facilities without any alteration due to its resistance and high stability. This study aims the complete degradation and partial mineralization of DCF by an ozonation process. The findings of the study suggest that increasing pH of the system and ozone supply rate, and generation of hydroxyl radicals in situ enhance the degradation process. In contrast, the increasing initial concentration of DCF slows down the process. The pseudo-first-order reaction rate constants were in the range of 0.0742 – –0.0979 min−1. A model has been developed to predict the behavior of the rate constant with various operating variables. High volumetric mass transfer coefficients (i.e., 1.150–2.717 × 103 s−1) was observed during the mass transfer study of ozone in water. A probable mechanism for ozonation is suggested along with the structures of major intermediates formed during the oxidation. Distinct orange pigments appeared during the reaction, which confirmed the production of DCF-2, 5-iminoquinone. Di-chloro aniline, 5-hydroxy DCF. The carboxylic acids were mainly detected as the metabolites. The treatment cost was estimated to be USD 0.80 for treating 1 m3 of the solution containing 50 mg dm−3 DCF. In addition, the effect of other water matrices on DCF degradation was also investigated and reported.

Label-free and visible-light driven photoelectrochemical sensor with CuCo2O4@CoO Core-shell hybrid rod as photoanode for selective sensing diclofenac

Diclofenac (DCF), the non-steroidal anti-inflammatory drugs (NSAIDs), remaining in environment as a heavily pollutants, the development of rapid and accurate method for sensing trace level DCF is urgent. Herein, a novel photoelectrochemical (PEC) sensing platform with CuCo2O4@CoO core-shell hybrid rods as photoanode was developed for rapidly sensing DCF without any additional recognition units. The Cu-based composite show specific interaction with carboxyl and imino group, it could selective absorbing and sensing DCF from other coexisting NSAIDs such as ibuprofen (IB), ketoprofen (KP) and flurbiprofen (FP) based on chelating ability and electrochemical activity. The synergistic effect of the well design core-shell structure combining close-connected heterojunction could enhance the sensitivity of the PEC sensor. The PEC response of the sensor was found to be linearly proportional to the concentration of DCF in the range from 10 nmol L-1 to 500 μmol L-1. The detection limit (3S/N) is 6.5 nmol L-1. The application of PEC sensor was evaluated by the determination of DCF in environment water samples, the spiked recoveries are in the range from 86.0 to 115.8%. The relative standard deviation (RSD) value of reproducibility and repeatability are less than 4.3 and 3.9%, showing excellent sensitivity, good reproducibility, repeatability and high stability. This strategy opens up a new avenue for the constructed high sensitivity and high selectivity PEC sensor.

Photobiomodulation therapy enhances topical diclofenac absorption in healthy volunteers – a randomized placebo-controlled trial: preliminary results

The inflammatory Muscle-skeletal disorders are responsible for a high economic impact on public health and Pharmacological treatments produce important renal and gastric toxicity especially. However, the real effects of topical NSAID’s still controversial. Photobiomodulation therapy has been used to treat musculo-skeletal conditions. The aim of this study was to evaluate the effects of Photobiomodulation on topical absorption of sodium diclofenac in healthy volunteers. Methods. The volunteers were selected after an assessment of their state of health. The study began with 12 volunteers with dark skin and 12 white skin. The study was designed to determinate the pharmacokinetic parameters. The volunteers received during hospitalization 5g diclofenac gel in the presence or not of photobiomodulation, following the randomization. A Laser Cluster with 14 laser diodes (100 mW/diode) delivered 3 Joules of Energy/diode (spot area 0.028 Cm2). Blood samples were taken for determination of plasmatic diclofenac concentration (0.5, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 18, 24h) by tandem mass spectrometry. Low Power Laser Therapy operating at a wavelength of 650 nm was effective to enhance the absorption of diclofenac emulgel in white-skinned individuals but not in black-skinned individuals. Maximum plasma concentrations were higher in the white-skinned group of volunteers who received low-power laser irradiation prior to drug application when compared to the placebo group.

H2O2-assisted Sonophotocatalytic Degradation of Diclofenac using a Visible Light-Active Flower-like Micron-sized TiO2 Photocatalyst

The recovery of TiO2 nanoparticles after utilization is a major challenge that hinders the wide-scale implementation of photocatalytic technology in wastewater treatment. In this study, an easily recoverable flower-shaped micron-sized TiO2 (MST) photocatalyst was synthesized from nano-sized TiO2 seeds via a hydrothermal process. The synthesized MST photocatalyst displayed an average particle size of 1.577 μm with 2.7 eV bandgap energy and 100.18 m2/g surface area. The photocatalytic performance of the synthesized material was evaluated for the degradation of diclofenac (DCF) from aqueous solution under visible light. The degradation efficiency under visible light reached 52.87% in 120 min. When photocatalysis was coupled with ultrasonication (US), namely sonophotocatalysis, the DCF degradation efficiency increased to 62.61%. The highest DCF degradation efficiency (86.92%) was achieved under the optimized conditions of 30 kHz US frequency, 0.4 g/L of TiO2 loading, 10 ppm initial concentration of DCF, and 1.0 mM H2O2 dosage. The synergy index of sonophotocatalysis was 1.25, indicating the synergistic effects of both sonocatalysis and photocatalysis on DCF degradation efficiency. The MST photocatalyst was easily recovered through centrifugation after reaction and reused for another two cycles of sonophotocatalysis. The photocatalyst was significantly stable under these process conditions, with only a 5.19% decrease in degradation after three consecutive cycles.

Insights of emerging contaminants removal in real water matrices by CWPO using a magnetic catalyst

The study was focused on the application of catalytic wet peroxide oxidation (CWPO) with a synthesized magnetic catalyst (Fe3O4/MWCNTs) for the treatment of real water matrices spiked with pharmaceutical compounds. CWPO was carried out by modifying the initial pH of surface water (SW), wastewater treatment plant (WWTP) effluent, brewery wastewater (BW) and hospital wastewater (HW), and the effect of the addition of the emerging pollutants naproxen (NAP) and diclofenac (DCF). From the experimental results, pH and concentration of NAP and DCF in CWPO were crucial factors in the successful pollutants removal from water matrices. The lab-prepared catalyst showed high removal rates of NAP and DCF from different water matrices spiked with the NAP-DCF mixture at pH 5.0. The highest average removal rate of TOC (75%), NAP (66%), DCF (76%), TN (39%) and aromaticity (68.39%) was obtained for SW matrix using 1.0 g L−1 of catalyst, pH ≈ 5.0, 5 mM of H2O2 and 60 °C. The mineralization decreased with the increase of the initial TOC concentration of the tested matrix. By CWPO tests of the real water matrices it was demonstrated that DCF removal was higher than NAP. From the recyclability tests, the catalyst demonstrated high activity and stability along three consecutive CWPO cycles of 8 h each one. The pseudo-second order model well-described the degradation of NAP and DCF. Finally, aromaticity and toxicity of the effluents were greatly reduced after CWPO treatment. This work demonstrated that CWPO with the magnetic catalyst is an efficient method to remove DCF-NAP mixtures from real aqueous matrices.