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Summary: A comprehensive study of the degradation of thiamethoxam (THIA) and metoprolol (MET) was conducted by using UV-induced photolysis (λ =254nm), ozonation, and a combination of these methods. In order to investigate how molecular structure of the substrate influences the rate of its degradation, we compared these three processes for the insecticide THIA and the drug MET (a β1-blocker). Of the three treatments applied, the UV photolysis and the combination of UV/O3 were found to be most effective in the degradation of THIA, while the UV/O3 process appeared to be the most efficient in terms of MET decay. The degradation kinetics was monitored by LC–DAD, and spectrophotometry, while the mineralization of the substrates was studied by TOC analysis. Reaction intermediates were studied in detail and a number of them were identified using LC–MS (ESI+/ESI−). Both parent compounds showed slight toxic effects towards algae Pseudokirchneriella subcapitata and bacteria Vibrio fischeri. However, the toxicity of the solutions containing also the degradation intermediates appeared to be much higher for all the test organisms. The inhibition/mortality rates were reduced most efficiently by the UV/O3 procedure. Ames test and Comet assay were used to follow the genotoxicity during the degradation of the studied compounds. Genotoxic intermediates were frequently detected in the case of MET in the UV treatment alone or in the presence of ozone. Treatments of THIA samples resulted less frequently in genotoxic intermediates. To our best knowledge, this work is the first genotoxicological investigation dealing with the photolytic degradation process of the studied compounds. [Copyright &y& Elsevier]

The persulfate-based advanced oxidation process is a promising method for degrading organic pollutants. Herein, TiO 2 and ZnO photocatalysts were combined with the peroxydisulfate ion (PDS) to enhance the efficiency. ZnO was significantly more efficient in PDS conversion and SO 4 •- generation than TiO 2 . For ZnO, the PDS increased the transformation rate of the trimethoprim antibiotic from 1.58 × 10 -7 M s -1 to 6.83 × 10 -7 M s -1 . However, in the case of TiO 2 , the moderated positive effect was manifested mainly in O 2 -free suspensions. The impact of dissolved O 2 and trimethoprim on PDS transformation was also studied. The results reflected that the interaction of O 2 , PDS, and TRIM with the surface of the photocatalyst and their competition for photogenerated charges must be considered. The effect of radical scavengers confirmed that in addition to SO 4 •- , • OH plays an essential role even in O 2 -free suspensions, and the contribution of SO 4 •- to the transformation is much more significant for ZnO than for TiO 2 . The negative impact of biologically treated domestic wastewater as a matrix was manifested, most probably because of the radical scavenging capacity of Cl - and HCO 3 - . Nevertheless, in the case of ZnO, the positive effect of PDS successfully overcompensates that, due to the efficient SO 4 •- generation. Reusability tests were performed in Milli-Q water and biologically treated domestic wastewater, and only a slight decrease in the reactivity of ZnO photocatalysts was observed.

The increasing prevalence of water insoluble or poorly soluble drugs calls for the development of new formulation methods. Common approaches include the reduction of particle size and degree of crystallinity. Pulsed laser ablation is a clean technique for producing sub-micrometre sized drug particles and has the potential to induce amorphization. We studied the effect of femtosecond pulsed laser ablation (ELI ALPS THz pump laser system: λ c  = 781 nm, τ = 135 fs) on meloxicam in distilled water and in air. The ablated particles were characterized chemically, morphologically and in terms of crystallinity. We demonstrated that femtosecond laser ablation can induce partial amorphization of the particles in addition to a reduction in particle size. In the case of femtosecond pulsed laser ablation in air, the formation of pure meloxicam spheres showed that this technique can produce amorphous meloxicam without the use of excipients, which is a unique result. We also aimed to describe the ablation processes in both investigated media., (© 2023. The Author(s).)

Recently, the number of water insoluble and poorly soluble drug compounds has increased significantly. Therefore, growing interest has been witnessed in different particle size reduction techniques to improve the dissolution rates, transport characteristics and bioavailability of drugs. Laser ablation has proven to be an alternative method to the production of nano- and micrometre-sized drug particles without considerable chemical damage. We present the nanosecond laser ablation of drug pastilles in distilled water, targeting meloxicam, a poorly water soluble nonsteroidal anti-inflammatory drug, at different laser wavelengths (248 nm, 532 nm and 1064 nm). Besides chemical characterization, crystallinity, morphology and particle size studies, the mechanism of the particle generation process was examined. The applicability of ablated particles in drug formulation was investigated by solubility, cytotoxicity and anti-inflammatory effect measurements. We showed that laser ablation is a clean, efficient and chemically non-damaging method to reduce the size of meloxicam particles to the sub-micrometre-few micrometre size range, which is optimal for pulmonary drug delivery. Complemented by the excellent solubility (four to nine times higher) and anti-inflammatory (four to five times better) properties of the particles compared to the initial drug, laser ablation is predicted to have wider applications in the development of drug formulations., (© 2022. The Author(s).)

The comparison of the efficiency of the commercially available photocatalysts, TiO 2 and ZnO, irradiated with 365 nm and 398 nm light, is presented for the removal of two antibiotics, sulfamethazine (SMT) and sulfamethoxypyridazine (SMP). The • OH formation rate was compared using coumarin, and higher efficiency was proved for TiO 2 than ZnO, while for 1,4-benzoquinone in O 2 -free suspensions, the higher contribution of the photogenerated electrons to the conversion was observed for ZnO than TiO 2 , especially at 398 nm irradiation. An extremely fast transformation and high quantum yield of SMP in the TiO 2 /LED 398nm process were observed. The transformation was fast in both O 2 containing and O 2 -free suspensions and takes place via desulfonation, while in other cases, mainly hydroxylated products form. The effect of reaction parameters (methanol, dissolved O 2 content, HCO 3 - and Cl - ) confirmed that a quite rarely observed energy transfer between the excited state P25 and SMP might be responsible for this unique behavior. In our opinion, these results highlight that "non-conventional" mechanisms could occur even in the case of the well-known TiO 2 photocatalyst, and the effect of wavelength is also worth investigating.

In this work, the application of high-power LED 365nm and commercial, low-price LED 398nm for heterogeneous photocatalysis with TiO 2 and ZnO photocatalysts are studied and compared, focusing on the effect of light intensity, photon energy, quantum yield, electrical energy consumption, and effect of matrices and inorganic components on radical formation. Coumarin (COU) and its hydroxylated product (7-HC) were used to investigate operating parameters on the • OH formation rate. In addition to COU, two neonicotinoids, imidacloprid and thiacloprid, were also used to study the effect of various LEDs, matrices, and inorganic ions. The transformation of COU was slower for LED 398nm than for LED 365nm , but r 0 7-HC /r 0 COU ratio was significantly higher for LED 398nm . The COU mineralization rate was the same for both photocatalysts using LED 365nm , but a significant difference was observed using LED 398nm . The impact of matrices and their main inorganic components Cl - and HCO 3 - were significantly different for ZnO and TiO 2 . The negative effect of HCO 3 - was evident, however, in the case of high-power LED 365nm and TiO 2 , and the formation of CO 3 •- almost doubled the r 0 7-HC and contributes to the conversion of neonicotinoids by altering the product distribution and mineralization rate.

BiOI, BiOCl, and their composites (BiOI:BiOCl) with molar ratios from 95:5 to 5:95 were synthesized and tested in the transformation of methyl orange (MO) and sulfamethoxypyridazine (SMP) antibiotic, using three various LED light sources: UV LEDs (398 nm), cool and warm white LEDs (400-700 nm). The 80:20 BiOI:BiOCl photocatalyst showed the best adsorption capacity for MO and enhanced activity compared to BiOI and BiOCl. The apparent quantum yield (Φ app ) of the MO and SMP transformation for cool and warm white light was slightly lower than for 398 nm UV radiation. The effect of methanol and 1,4-benzoquinone proved that the transformation is initiated mainly via direct charge transfer, resulting in the demethylation of MO and SO 2 extrusion from SMP. The change of photocatalytic efficiency was followed during three cycles. After the first one, the transformation rates decreased, but there was no significant difference between the second and third cycles. The decreased efficiency is most probably caused by the intermediates, whose continuous accumulation was observed during the cycles. Ecotoxicity measurements confirmed that no toxic substances were leached from the catalyst, but the transformation of both MO and SMP results in toxic intermediates. Using 80:20 BiOI:BiOCl and LED light source, the energy requirement of the removal is about half of the value determined using TiO 2 and a mercury vapor lamp. The effect of some components of wastewater (Cl - , HCO 3 - and humic acids), pH, and two matrices on the composite photocatalysts' efficiency and stability were also investigated., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pharmaceuticals and pesticides are emerging contaminants problematic in the aquatic environment because of their adverse effects on aquatic life and humans. In order to remove them from water, photocatalysis is one of the most modern technologies to be used. First, newly synthesized photocatalysts were successfully prepared using a sol-gel method and characterized by different techniques (XRD, FTIR, UV/Vis, BET and SEM/EDX). The photocatalytic properties of TiO 2 , ZnO and MgO nanoparticles were examined according to their removal from water for two antibiotics (ciprofloxacin and ceftriaxone) and two herbicides (tembotrione and fluroxypyr) exposed to UV/simulated sunlight (SS). TiO 2 proved to be the most efficient nanopowder under UV and SS. Addition of (NH 4 ) 2 S 2 O 8 led to the faster removal of both antibiotics and herbicide fluroxypyr. The main intermediates were separated and identified for the herbicides and antibiotic ciprofloxacin. Finally, the toxicity of each emerging pollutant mixture and formed intermediates was assessed on wheat germination and biomass production.

Nowadays, great focus is given to the contamination of surface and groundwater because of the extensive usage of pesticides in agriculture. The improvements of commercial catalyst TiO 2 activity using different Au nanoparticles were investigated for mesotrione photocatalytic degradation under simulated sunlight. The selected system was 2.43 × 10 -3 % Au-S-CH 2 -CH 2 -OH/TiO 2 (0.5 g/L) that was studied by transmission electron microscopy and ultraviolet-visible (UV-Vis) spectroscopy. It was found that TiO 2 particles size was ~20 nm and ~50 nm, respectively. The Au nanoparticles were below 10 nm and were well distributed within the framework of TiO 2 . For 2.43 × 10 -3 % Au-S-CH 2 -CH 2 -OH/TiO 2 (0.5 g/L), band gap energy was 2.45 eV. In comparison to the pure TiO 2 , addition of Au nanoparticles generally enhanced photocatalytic removal of mesotrione. By examining the degree of mineralization, it was found that 2.43 × 10 -3 % Au-S-CH 2 -CH 2 -OH/TiO 2 (0.5 g/L) system was the most efficient for the removal of the mesotrione and intermediates. The effect of tert -butanol, NaF and ethylenediaminetetraacetic acid disodium salt on the transformation rate suggested that the relative contribution of various reactive species changed in following order: h + > ● OH ads > ● OH bulk . Finally, several intermediates that were formed during the photocatalytic treatment of mesotrione were identified.

Four techniques, UV 254 nm photolysis, vacuum ultraviolet (VUV 172 nm ) photolysis, combined UV 254 nm /VUV 185 nm photolysis and gamma (γ) radiolysis were used to induce the transformation of atrazine in aqueous solution. The effects of dissolved oxygen (atrazine concentration 1 × 10 -4  mol L -1 and 4.6 × 10 -7  mol L -1 ) and matrix (high purity water/purified wastewater, atrazine concentration 4.6 × 10 -7  mol L -1 ) and the electric energy requirements were investigated. The calculation of the energy input in cases of the photolyses was based on the lamp's power. In radiolysis, the absorbed dose (J kg -1 ) was the basis. In UV photolysis, atrazine transforms to atrazine-2-hydroxy; this product practically does not degrade during UV photolysis; due to this reason, the mineralisation is very slow. This and some other products of atrazine decomposition degrade only in radical reactions. Dissolved oxygen usually slightly enhances the degradation rate. At 10 -7  mol L -1 concentration level, the matrix, high purity water/purified wastewater, has not much influence on the degradation rates in UV photolysis and radiolysis. In the VUV and UV/VUV systems, considerable matrix effects were observed. Comparing the electric energy requirements of the four degradation processes, radiolysis was found to be the economically most feasible method, requiring 1-2 orders of magnitude less electric energy than UV/VUV, VUV and UV photolysis.

Levodopa (LEVO) as the gold standard in the treatment of Parkinson's disease is usually administrated per os but its bioavailability is low. The intranasal administration is a potential alternative route to increase bioavailability of the drug and treat the off period. Our aim was to develop LEVO-containing binary nasal powders with different excipients by dry cogrinding process. The interactions between the components were examined. The optimized cogrinding process parameters (LEVO:excipient ratio and grinding time) resulted in the desired particle size range (5-40 μm). The α-cyclodextrin and poly(vinylpyrrolidone) (PVP) had an intensive crystallinity degree reducing effect on LEVO measured by XRPD, and they functioned as cogrinding agents. Hydroxypropyl methylcellulose, poly (vinyl alcohol) (PVA), and D-mannitol associate around the LEVO crystals preventing its crystalline structure. Hydrogen bonding was detected only for LEVO-PVP and LEVO-D-mannitol used Fourier-transformed infrared spectroscopy. Chemical degradation of LEVO in the products was not detected even after the accelerated stability test. The dissolution profile of the products can be characterized by the first-order kinetic model with different dissolution rate. The dissolution rate of LEVO was increased with α-cyclodextrin and PVP, and the drug release decreased in the case of hydroxypropyl methylcellulose, PVA, and D-mannitol compared to the LEVO powder., (Copyright © 2019 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Homeostatic disruptor agents, and endocrine disruptor compounds (EDC) specifically, can originate from agricultural and industrial chemicals. If they modify the adaptation of living organisms as direct (e.g., by altering hormone regulation, membrane functions) and/or indirect (e.g., cell transformation mechanisms) factors, they are classified as EDC. We aimed to examine the potential endocrine-disrupting effects of phenylurea herbicides (phenuron, monuron, and diuron) on the oxytocin (OT) and arginine-vasopressin (AVP) release of neurohypophysis cell cultures (NH). In our experiments, monoamine-activated receptor functions of neurohypophyseal cells were used as a model. In vitro NH were prepared by enzymatic (trypsin, collagenase) and mechanical dissociation. In the experimental protocol, the basal levels of OT and AVP were determined as controls. Later, monoamine (epinephrine, norepinephrine, serotonin, histamine, and dopamine) activation (10 -6  M, 30 min) and the effects of phenylurea (10 -6  M, 60 min) alone and in combination (monoamines 10 -6  M, 30 min + phenylureas 10 -6  M, 60 min) with monoamine were studied. OT and AVP hormone contents in the supernatant media were measured by radioimmunoassay. The monoamine-activated receptor functions of neurohypophyseal cells were modified by the applied doses of phenuron, monuron, and diuron. It is concluded that the applied phenylurea herbicides are endocrine disruptor agents, at least in vitro for neurohypophysis function.

Uron herbicides polluting the environment represent a serious concern for environmental health and may be regarded as endocrine-disrupting compounds (EDCs), which influence the regulation of human homeostasis. We aimed to investigate the effect of EDC urons (phenuron: PU, monuron: MU, and diuron: DU) and chlorobenzenes on the basal release of the adrenocorticotropic hormone (ACTH), which is a part of the adenohypophysis-adrenocortical axis. Hormone secretion in the presence of EDC was studied in two cell types: normal adenohypophysis cells (AdH) and cells of prolactinomas (PRLOMA). PRLOMA was induced in female Wistar rats by subcutaneously injecting them with estrone acetate for 6 months. AdH and PRLOMA were separated from treated and untreated experimental animals, dissociated enzymatically and mechanically in order to create monolayer cell cultures, which served as an experimental in vitro model. We investigated the effects of ED agents separately and in combination on ACTH and prolactin (PRL) release through the hypophyseal-adrenal axis. Hormone determination was carried out by the luminescent immunoassay and the radioimmunoassay methods. Our results showed that (1) uron agents separately did not change ACTH and PRL release in AdH culture; (2) ACTH secretion in arginine vasopressin- (AVP-) activated AdH cells was significantly increased by EDC treatment; (3) ED agents increased the basal hormone release (ACTH, PRL) in PRLOMA cells; and (4) EDC exposure increased ACTH release in AVP-activated PRLOMA cells. We conclude that the herbicides PU, MU, and DU carry EDC effects and show human toxicity potential.

Various types of advanced oxidation processes (AOPs), such as UV photolysis, ozonation, heterogeneous photocatalysis and their combinations were comparatively examined at the same energy input in a home-made reactor. The oxidative transformations of the phenylurea herbicides fenuron, monuron and diuron were investigated. The initial rates of transformation demonstrated that UV photolysis was highly efficient in the cases of diuron and monuron. Ozonation proved to be much more effective in the transformation of fenuron than in those of the chlorine containing monuron and diuron. In heterogeneous photocatalysis, the rate of decomposition decreased with increase of the number of chlorine atoms in the target molecule. Addition of ozone to UV-irradiated solutions and/or TiO2-containing suspensions markedly increased the initial rates of degradation. Dehalogenation of monuron and diuron showed that each of these procedures is suitable for the simultaneous removal of chlorinated pesticides and their chlorinated intermediates. Heterogeneous photocatalysis was found to be effective in the mineralization.

The effects of dissolved O2, phosphate buffer and the initial concentration of diclofenac on the vacuum ultraviolet photolysis of this contaminant molecule were studied. Besides kinetic measurements, the irradiated, multicomponent samples were characterized via the proliferation and migratory responses (in sublethal concentrations) of the bioindicator eukaryotic ciliate Tetrahymena pyriformis. The results suggest that hydroxyl radicals, hydrogen atoms and hydroperoxyl radicals may all contribute to the degradation of diclofenac. The aromatic by-products of diclofenac were presumed to include a hydroxylated derivative, 1-(8-chlorocarbazolyl)acetic acid and 1-(8-hydroxycarbazolyl)acetic acid. The biological activity of photoexposed samples reflected the chemical transformation of diclofenac and was also dependent on the level of dissolved O2. The increase in toxicity of samples taken after different irradiation times did not exceed a factor of two. Our results suggest that the combination of vacuum ultraviolet photolysis with toxicity and chemotactic measurements can be a valuable method for the investigation of the elimination of micropollutants., (© 2013.)

Naproxen is a widely used nonsteroidal anti-inflammatory drug. Recently, this medicine was detected both in natural waters (up to 1.5 μg L(-1)) and in sewage treatment plant effluents (up to 5.2 μg L(-1)). Moreover, naproxen is only partly eliminated by classical processes used in sewage treatment plants. Therefore, its degradation is of utmost interest. Advanced oxidation processes proved to be the most suitable methods for the elimination of persistent organic contaminants. In this work ultraviolet (UV, 254 nm), vacuum ultraviolet photolysis (VUV, 172 nm) and their combination (UV/VUV, 254/185 nm) were investigated. The efficiency of the methods increased in the following order: UV < VUV < UV/VUV photolysis. However, VUV irradiation was found to mineralize the contaminant molecule most effectively. The chemical structures of three out of four aromatic by-products and of some aliphatic carboxylic acids were presumed. The effects of dissolved O2 and the initial concentration of naproxen on the degradation were also investigated., (Copyright © 2013 Elsevier B.V. All rights reserved.)