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Gold chloride clusters play an important role in catalysis and materials chemistry. Due to the diversity of their species and isomers, there is still a dearth of structural studies at the molecular level. In this work, anions of AunCln+3- and AunCln+5- (n = 2–4) clusters were obtained by laser desorption/ionization mass spectrometry (LDI MS), and the most stable isomers of AunCln+3- were determined after a thorough search and optimization at the TPSSh/aug-cc-pVTZ/ECP60MDF level. The results indicate that all isomers with the lowest energy have a planar zigzag skeleton. In each species, there is one Au(III) atom at the edge connected with four Cl atoms, which sets it from the other Au(I) atoms. Four growth pathways for AunCln+3- (n = 2–7) clusters are proposed (labelled R1, R2, R3 and R4). They are all associated with an aurophilic contact and are exothermic. The binding energies tend to stabilize at ~ −41 kcal/mol when the size of the cluster increases in all pathways. The pathway R1, which connects all the most stable isomers of the respective clusters, is characterized by cluster growth due to aurophilic interactions at the terminal atom of Au(I) in the zigzag chains. In the pathway of R4 involving Au-Au bonding in its initial structures (n ≤ 3), the distance between intermediate gold atoms grows with cluster size, ultimately resulting in the transfer of the intermediate Au-Au bonding into aurophilic interaction. The size effect on the structure and aurophilic interactions of these clusters will be better understood based on these discoveries, potentially providing new insights into the active but elusive chemical species involved in the corresponding catalytic reactions or nanoparticle synthesis processes.

This chapter summarizes the experimental methods used to obtain “superalkali” clusters. First, a brief review of the names, classifications and descriptions of the chemical structure of these clusters useful for explaining the experimental research was given. In the next part of the chapter, the various methods of mass spectrometry are presented, with emphasis on the study of the evaporation of individual salts of alkali halides or their mixtures, where “superalkali” clusters are inevitably detected. Surface ionization (thermal ionization) and the Knudsen effusion cell are two standard techniques that have been used in mass spectrometry for many years and have played an important role in the field of “superalkali” clusters from their discovery to the present. For this reason, the basic principles of operation of the surface ionization source and the Knudsen cell have been presented, along with a brief history of the origin and application of these methods. Some new possibilities of using the Knudsen cell in the mass spectrometer are pointed out, as well as the possibility of combining surface ionization and the Knudsen cell to obtain “superalkali” clusters. The possibilities of determining ionization energies by these two methods are also described.

Nanoparticles (NPs), a distinct class of particles ranging in size from 1 to 100 nm, are one of the most promising technologies of the 21st century, and titanium dioxide NPs (TiO2 NPs) are among the most widely produced and used NPs globally. The increased application of TiO2 NPs raises concerns regarding their global safety and risks of exposure. Many animal studies have reported the accumulation of TiO2 NPs in female reproductive organs; however, evidence of the resultant toxicity remains ambiguous. Since the surface area and chemical modifications of NPs can significantly change their cytotoxicity, we aimed to compare the toxic effects of pristine TiO2 powder with surface-modified TiO2 powders with salicylic acid (TiO2/SA) and 5-aminosalicylic acid (TiO2/5-ASA) on the ovaries, oviducts, and uterus on the 14th day following acute oral treatment. The results, based on alterations in food and water intake, body mass, organ-to-body mass ratio, hormonal status, histological features of tissues of interest, and antioxidant parameters, suggest that the modification with 5-ASA can mitigate some of the observed toxic effects of TiO2 powder and encourage future investigations to create NPs that can potentially reduce the harmful effects of TiO2 NPs while preserving their positive impacts.

This study is focused on the detailed examination of the combustion properties and kinetic analysis of a cellulose acetate fibrous bundle (CAFB), separated from used cigarette filters. It was shown that the faster rate of CAFB heating allows a large amount of heat to be supplied to a combustion system in the initial stages, where the increase in heating rate has a positive response to ignition behavior. The best combustion stability of CAFB is achieved at the lowest heating rate. Through the use of different kinetic methods, it was shown that combustion takes place through two series of consecutive reaction steps and one independent single-step reaction. By optimizing the kinetic parameters within the proposed reaction models, it was found that the steps related to the generation of levoglucosenone (LGO) (by catalytic dehydration of levoglucosan (LG)) and acrolein (by breakdown of glycerol during CAFB burning—which was carried out through glycerol adsorption on a TiO2 surface in a the developed dehydration mechanism) represent rate-controlling steps, which are strongly controlled by applied heating rate. Isothermal predictions have shown that CAFB manifests very good long-term stability at 60 °C (which corresponds to storage in a sea shipping container), while at 200 °C, it shows a sudden loss in thermal stability, which is related to the physical properties of the sample.

This work presents the perspective of applying the laser desorption/ionization mass spectrometry (LDI MS) for characterization the anode film of the Ag60Cu26Zn14, Ag58.5Cu31.5Pd10, and Ag63Cu27In10 alloys (at high concentrations of chloride ions in solutions). The reference LDI mass spectra of anode films of pure Ag and Cu have been used for the identification of product corrosion. Knowing the clusters detected in the reference spectra lead to the facilitating identification of the LDI mass spectrum of the sample and reduces the analysis time. The LDI MS analysis of these alloys revealed that the predominant corrosion product are AgCl (from AgnCln+1−/+, n = 1–3), and CuCl (from “superhalogen” CumCln− clusters, m = 1–2, n = 2–6); it also revealed Cu2(OH)3Cl (from Cu2(OH)(H2O)2+) and Cu2O (from Cu(H2O)+, Cu2O doped with chlorine). These results are in accordance with the X-ray diffraction and Raman analysis. The LDI MS spectra of alloys contain the additional peaks formed due to the mutual influences of different metals in the alloys (AgCuCl3− (AgCl-CuCl2−), AgCu2Cl4− (AgCl-CuCl-CuCl2−), and Ag2CuCl4− (AgCl-AgCl-CuCl−), which is consistent with the identified corrosion products. It should be noted that the LDI MS suggest the presence of CuCl2, which can be interpreted as the corrosion products retained in the porous films of alloys, and not detected by the other methods due to a small amount. The future theoretical and experimental studies of metal clusters, significant for metallurgy, can contribute that the LDI MS is becoming a powerful analytical tool for characterization the metal surfaces.

This paper considers possible uses of fruit-based waste for the production of valuable chemicals and biofuel precursors through recycling by thermochemical conversion. Slow pyrolysis of goji berry mesocarp as sugar-riched feedstock was investigated using simultaneous thermal analysis measurements in non-isothermal conditions. This work announced that pyrolysis of goji berry mesocarp represents a promising route to obtaining an important key platform chemical - 5- hydroxymethylfurfural (5-HMF). To establish the process mechanism, two kinetic approaches were used for kinetic parameters determination: first, Friedman’s and Vyazovkin’s model-free (inverse) methods supported by numerical optimization of the process, and second, the modelbased (direct) method. Model-free results showed a complex evolution of activation energy with conversion, indicating a multi-step mechanism. It was found that autocatalytic dehydration of fructose (in the presence of Lewis acids) is responsible for the production of 5-HMF at a low heating rate (5.0 K/min) with a maximum 5-HMF theoretical yield of 63.20 %. Higher heating rates (10.0 K/min and 15.0 K/min) trigger the fructose autogenesis behavior which opens the transferability channel to glucose (substrate) engagement for 5-HMF theoretical high yield production. It was revealed that differences between kinetic parameters are a consequence of the change in the mechanism of glycosidic bond cleavage. The validity of the proposed reaction mechanism scheme and accuracy of kinetic parameters was confirmed by modulated dynamic predictions.

Titanium dioxide nanoparticles (TiO2NPs) are widely used in pharmaceutics, food products and cosmetics. Besides numerous beneficial outcomes, they also induce toxic effects in different organs, including the eyes. The recent findings report that some surface modifications can attenuate TiO2NPs toxicity. Thus, the aim of this study was to compare the effects of acute oral treatment with commercially available, bare TiO2NPs and TiO2NPs surface modified with salicylic acid (SA-TiO2NPs) using adult Wistar rats as model organisms. Control animals were gastrically intubated with vehicle (0.01 M HCl), while others were treated with either TiO2NPs or SA-TiO2NPs (1000mg/kg dissolved in vehicle). Afterward, the mortality rate as the acute toxicity parameter and parameters of neurological function were assessed. Animals were sacrificed on the 14th day following treatment. In the eye crude synaptosomal fraction, the effects of treatments on oxidative stress markers such as prooxidant/antioxidant balance (PAB) and lipid peroxidation (LPO) were compared. According to the obtained results, the mortality was 0 in all experimental groups. TiO2NPs and SA-TiO2NPs treatments displayed mild effects on spontaneous activity and pacing and had no impact on the visual placing reflex. Moreover, TiO2NPs and SA-TiO2NPs exposure significantly elevated PAB levels, when compared to controls. Animals treated with SA-TiO2NPs had similar LPO levels as controls, while in TiO2NPs group LPO levels were significantly increased. The presented data showed that both examined nanoparticles exerted similar outcomes referring to most of the investigated parameters, however, surface binding of SA decreased the level of LPO and thus, mitigated some of TiO2NPs toxicity in the eyes.

This paper presents the results for gross alpha and gross beta activity in leaves samples: Fig (Ficus carica), Vine (Vitis vinifera L.), and Apricot (Prunus armeniaca). Samples were collected in Iraq (Sulaymaniyah, Kurdistan region), and in the Serbia (Belgrade), in the summer 2018. The analysis was done in dried and milled samples as well as in the annealed samples, using gas flow proportional counter. Determination of gross alpha and gross beta activity presents rapid method, essential for the analysis of radioactivity in environmental samples. The gross alpha activity is defines as the total activity of alpha emitters, and originates from the decay chains of 238U and 232Th, which quantity depends on the geological and geographical formation of natural radionuclides. The main contributor to the gross beta activity is natural long-lived isotope 40K, as well as 210Pb, 228Ra. The gross beta measurements also include a contribution from anthropogenic radionuclides 137Cs and 90Sr. Radionuclides that emitting low-energy beta radiation (3 H and gaseous or volatile radionuclide such as iodine) cannot be detected by gross beta activity measurements.

This paper presents application of a nuclear technique for the analysis of radioactivity in supplements using gas proportional counter as well as application of analytical technique Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS) in order to characterize the radioactivity contents and stability of the chemical structures for commercial supplements. Gas proportional counter enables to determination of gross alpha and gross beta activity in the environmental samples, where they are present as ultra trace elements. Also, MALDI-MS method is used, since it represents an excellent analytical technique for detecting large number of biologically important molecules, such as commercial supplements.

Mnogi teorijski proračuni su pokazali da su litijumom dekorisni borani (BxHy) ili klasteri bora (Bn) potencijalni materijali za skladištenje vodonika. Pored toga, pokazalo se da klasteri litijumfluorida poboljšavaju kapacitet skladištenja vodonika bolje od samog litijuma. Međutim, broj eksperimentalnih studija je mnogo manji. Zbog toga je u ovom radu ispitivana mogućnost interakcije klastera litijuma ili litijumfluorida sa boranima, metodom laserske desorpcione/jonizacione masenespektrometrije (LDI MS). Preliminarni rezultati su pokazali da negativni mod LDI maseni spektri suspenzije LiF/B (1:3) u dejonizovanoj vodi sadrži Li2(BH18) - , LiF2(BH3) - , LiB2(BH3)2 - , LiF2LiB(BH4)2 - jone. Smanjenje sadržaja bora u LiF/B sistemu (1:1) rezultira malo izmenjenim masenim spektrom. Intenzitet Li2(BH18) - i LiF2(BH3) - opada, dok druga dva jona pokazuju blago izmenjen sastav: Li2F(B3H2) - i LiF2(BH5)3 - . Rezultati pokazuju da klasteri Li2 i “superhalogen” LiF2 mogu da interaguju sa boranima. U oba slučaja, najintenzivniji joni su bili kompleksi između „superhalogena“-LiF2 i borana., Many theoretical calculations have shown that lithium decoration of borane (BxHy) or boron (Bn) clusters are potential materials for hydrogen storage. In addition, lithium fluoride clusters have been shown to improve hydrogen storage capacity better than lithium itself. However, the number of experimental studies is much smaller. Therefore, in this work, the possibility of interaction of lithium or lithium fluoride clusters with boranes was investigated by laser desorption/ionization mass spectrometry (LDI MS). The preliminary results have shown that the negative mode LDI mass spectra of the suspension of LiF/B (1:3) in deionized water include Li2(BH18) - , LiF2(BH3) - , LiB2(BH3)2 - LiF2LiB(BH4)2 - ions. The reducing the boron content in the LiF/B system (1:1) results in a little changed mass spectrum. The intensities of Li2(BH18) - and LiF2(BH3) - decrease, while two other ions show a slightly changed composition: Li2F(B3H2) - and LiF2(BH5)3 - . The results show that the Li2 and “superhalogen” LiF2 clusters can interact with boranes. In both cases, the most intense ions were complexes between “superhalogen”-LiF2 and boranes.

This paper considers possible uses of fruit-based waste for the production of valuable chemicals and biofuel precursors through recycling by thermochemical conversion. Slow pyrolysis of goji berry mesocarp as sugar-riched feedstock was investigated using simultaneous thermal analysis measurements in non-isothermal conditions. This work announced that pyrolysis of goji berry mesocarp represents a promising route to obtaining an important key platform chemical - 5-hydroxymethylfurfural (5-HMF). To establish the process mechanism, two kinetic approaches were used for kinetic parameters determination: first, Friedman’s and Vyazovkin’s model-free (inverse) methods supported by numerical optimization of the process, and second, the model-based (direct) method. Model-free results showed a complex evolution of activation energy with conversion, indicating a multi-step mechanism. It was found that autocatalytic dehydration of fructose (in the presence of Lewis acids) is responsible for the production of 5-HMF at a low heating rate (5.0 K/min) with a maximum 5-HMF theoretical yield of 63.20 %. Higher heating rates (10.0 K/min and 15.0 K/min) trigger the fructose autogenesis behavior which opens the transferability channel to glucose (substrate) engagement for 5-HMF theoretical high yield production. It was revealed that differences between kinetic parameters are a consequence of the change in the mechanism of glycosidic bond cleavage. The validity of the proposed reaction mechanism scheme and accuracy of kinetic parameters was confirmed by modulated dynamic predictions.

Polymers and polymer composites have wide application in every industrial field, and are a subject of continuous research from different scientific aspects [1,2]. However, most commercial polymers are oil refinery based products. Recently, due to a growing concern for oil depletion, researchers have been focused on modification of polymers, as well as reinforcements [3,4]. Epoxy resin is the most commonly used adhesive that can be improved with fiber or particle reinforcements, or by using chemical modifiers. Modifying agents from renewable resources show potential in replacing oil-based compounds, because of their abundance, low price and heterogeneous structure that offers number of reactive groups [5]. In our research, honey was used as a bio-based modifier for diglycidyl ether of bisphenolA (DGEBA) based epoxy resin, with the aim of investigating structural changes. MALDI-TOF mass spectrometry [6] was used as a powerful technique that is able to reveal presence of functional groups and modified epoxy resin structure. In this manner, successful chemical modification of epoxy resin was confirmed, which further opened the path for the investigation of honey potential as epoxy modifying agent.

Titanium dioxide nanoparticles (Ti02 NPs) are widely used in different cosmetic products, food additives and pharmaceuticals. Their accumulation within the body is associated with adverse health effects. Since animal studies indicate that their outcomes could be ameliorated by different modifications, we tested the impact of Ti02 NPs surface-modified with 5-aminosalicylic acid (Ti02/5-ASA NPs) in female adult Wistar rats. For the purpose of this experiment,14 days following the acute oral intake, the effects of commercially available Ti02 NPs and i02/5-ASA NPs were compared, using well defined methods, to assess the signs of acute toxicity (agitation, convulsion, and mortality) and neurological function (visual placing, spontaneous activity, and pacing/circling) along with the levels of end products of lipid peroxidation (LPP) in eyes. Our results indicate that following the treatments, spontaneous activity was disturbed while mortality, convulsion and visual placing were unaltered. The modification decreased Ti02 NPs-induced impairment of agitation and pacing/circling. The insight into biomolecules in the eyes, more precisely into a marker of oxidative stress (LPP), showed that it was decreased after treatment with Ti02/5-ASA NPs in comparison to Ti02 NPs, indicating that this type of modification might mitigate Ti02 NPs-induced oxidative stress. According to obtained results, even though the exact mechanism of the actions is still unknown, the modification with 5-aminosalicylic acid alleviates toxic effects of commercially available Ti02 NPs.

It is known that the “superalkali” cluster Li2F can significantly improve the hydrogen storage capabilities in carbon materials; boron compounds play a similar role. However, the possibility of interactions of lithium fluoride clusters with boron and hydrogen has not been investigated so far. In this work, a laser desorption/ionization mass spectrometry (LDI MS) was used for this purpose. Preliminary results showed that the interaction between the “superalkali” Li3F cluster, boron and six hydrogen atoms is possible; the ion Li3FBH6+ was detected. Non-stoichiometric clusters of lithium fluoride can also combine with boron and hydrogen in the following manner: Li5F2BH5+ Li5F3BH2+ Li4F5BH4+ Li6F2B6H+, and Li8F6H+.

The careful monitoring of patients with mild/moderate COVID-19 is of particular importance because of the rapid progression of complications associated with COVID-19. For prognostic reasons and for the economic management of health care resources, additional biomarkers need to be identified, and their monitoring can conceivably be performed in the early stages of the disease. In this retrospective cross-sectional study, we found that serum concentrations of high-mobility group box 1 (HMGB1) and heme oxygenase-1 (HO-1), at the time of hospital admission, could be useful biomarkers for COVID-19 management. The study included 160 randomly selected recovered patients with mild to moderate COVID-19 on admission. Compared with healthy controls, serum HMGB1 and HO-1 levels increased by 487.6 pg/mL versus 43.1 pg/mL and 1497.7 pg/mL versus 756.1 pg/mL, respectively. Serum HO-1 correlated significantly with serum HMGB1, oxidative stress parameters (malondialdehyde (MDA), the phosphatidylcholine/lysophosphatidylcholine ratio (PC/LPC), the ratio of reduced and oxidative glutathione (GSH/GSSG)), and anti-inflammatory acute phase proteins (ferritin, haptoglobin). Increased heme catabolism/hemolysis were not detected. We hypothesize that the increase in HO-1 in the early phase of COVID-19 disease is likely to have a survival benefit by providing protection against oxidative stress and inflammation, whereas the level of HMGB1 increase reflects the activity of the innate immune system and represents levels within which the disease can be kept under control.

High performance polymers with bio-based modifiers are promising materials in terms of applications and environmental impact. In this work, raw acacia honey was used as a bio-modifier for epoxy resin, as a rich source of functional groups. The addition of honey resulted in the formation of highly stable structures that were observed in scanning electron microscopy images as separate phases at the fracture surface, which were involved in the toughening of the resin. Structural changes were investigated, revealing the formation of a new aldehyde carbonyl group. Thermal analysis confirmed the formation of products that were stable up to 600 °C, with a glass transition temperature of 228 °C. An energy-controlled impact test was performed to compare the absorbed impact energy of bio-modified epoxy containing different amounts of honey with unmodified epoxy resin. The results showed that bio-modified epoxy resin with 3 wt% of acacia honey could withstand several impacts with full recovery, while unmodified epoxy resin broke at first impact. The absorbed energy at first impact was 2.5 times higher for bio-modified epoxy resin than it was for unmodified epoxy resin. In this manner, by using simple preparation and a raw material that is abundant in nature, a novel epoxy with high thermal and impact resistance was obtained, opening a path for further research in this field.

Cerebral hypoperfusion (CH) is recognised as a contributor to various impairments characteristic for elderly population and patients with vascular dementia and Alzheimer’s disease. CH-induced brain damage is linked with oxidative stress in the cells that can cause DNA fragmentation and cell death, reflected through a change in cells’ morphology. Our study investigated the beneficial effects of progesterone (P4), a hormone with neuroprotective properties, against CH-induced oxidative stress and neurodegenerative pathologies in rat prefrontal cortex (PFC). For the purpose of the experiment, adult male Wistar rats were dived into groups: (I) animals subjected to permanent bilateral occlusion of common carotid arteries (2VO) treated with vehicle (commercial flax oil, 1 mg/kg/day), (II) animals subjected to 2VO treated with P4 dissolved in vehicle (1.7 mg/kg/day) and (III) animals subjected to sham operation treated with vehicle. Animals were sacrificed after 7 subcutaneous treatments. Levels of pro-/antioxidant balance (PAB) and DNA fragmentation along with cell morphology were estimated by well-defined methods. The results revealed that P4 administration moderated CH-induced impairments in PFC, not only by decreasing PAB level and diminishing DNA fragmentation, but also preserving the cell morphology reflected through clearly defined cell bodies, with round nuclei, prominent nucleolus and visible Nissl bodies in layer III. Obtained results point out that P4 is able to attenuate CH-induced pro-oxidant state and subsequent changes in PFC. This hormone holds promise as an effective agent for the CH treatment, still, its specific actions remain to be discovered.

Prolonged disturbance of cerebral blood flow causes metabolic insufficiency and neuronal hypofunction, for which there is still no adequate therapeutic strategy. In several animal models of neurodegenerative diseases, progesterone (P4), a potent gonadal steroid hormone, and its metabolites showed neuroprotective outcomes through reduction of oxidative stress and stabilization of membrane lipids and their downstream signalling. As P4 actions in rat striatum following permanent bilateral occlusion of both common carotid arteries are still uncertain, we investigated its capacity to reduce neuronal damage induced by permanent occlusion of both carotid arteries (2VO), focusing on several oxidative stress markers (end products of lipid peroxidation (LPP) and phosphatidylcholine (PC) to lysophosphatidylcholine (LPC) intensity ratio) in crude synaptosomal fraction. Adult male Wistar rats were divided into groups: control ‒ sham operated animals treated with vehicle (commercial flax oil, 1 mg/kg) and permanently occluded animals subjected to either vehicle (commercial flax oil, 1 mg/kg) or P4 (dissolved in commercial flax oil, 1.7 mg/kg). Animals were subcutaneously injected for 7 days and sacrificed 4 h following the last treatment. LPP levels were determined spectrophotometrically, while PC/LPC intensity ratio was estimated by mass spectrometer. Obtained results indicate that P4 treatment alleviates 2VO – induced prooxidative changes by decreasing LPP levels and elevating PC/LPC intensity ratio, and returning them closer to levels observed in controls. According to our findings, P4 treatment in cerebral hypoperfusion model, via targeting striatal cell lipid components and altering lipid profile, might be implicated in reduction of oxidative stress and promotion of protective environment.

This work considers possible uses of fruit-based waste for the production of valuable chemicals and biofuel precursors through recycling by thermochemical conversion. Slow pyrolysis of Goji berry mesocarp (GBM) as sugar-rich feedstock was investigated using simultaneous thermal analysis (STA) measurements in non-isothermal conditions. Results reveal that pyrolysis of GBM represents a promising route to obtain important key platform chemical - 5-hydroxymethylfurfural (5-HMF). It was found that autocatalytic dehydration of fructose (in a presence of Lewis acids) is responsible for production of 5-HMF at a low heating rate (5.0 K/min) with a maximum 5-HMF theoretical yield of 63.20 %. Higher heating rates (10.0 and 15.0 K/min) trigger fructose autogenesis behavior which opens the transferability channel to glucose engagement for 5-HMF theoretical high yield production.

Široka primena nanočestica titanijum-dioksida (TiO2 NČ) u medicini, farmaceutskoj, prehrambenoj i hemijskoj industriji,1 čini TiO2 NČ visoko zastupljenim u životnoj sredini i svim sferama čovekovog života. Negativne efekte ostvaruju u mozgu, s obzirom da lako prolaze krvno-moždanu barijeru, akumuliraju se u različitim regionima mozga i indukuju oksidativni stres tokom kog se oštećuju svi biomolekuli, uključujući i lipide.2 Literaturni podaci ukazuju da različite modifikacije mogu ublažiti uočene efekte, stoga je cilj ovog rada bio da se uporedi odgovor odraslih Wistar pacova 14 dana nakon jednokratnog oralnog tretmana sa komercijalno dostupnim TiO2 NČ i TiO2 NČ površinski modifikovanim salicilnom (TiO2/SK NČ) odnosno 5- aminosalicilnom kiselinom (TiO2/5-ASK NČ). Odgovarajućim testovima praćene su promene parametara senzorno-motorne funkcije (SMF), kao pokazatelja neurološkog deficita, dok je oksidativni stres praćen promenom nivoa lipidne peroksidacije (LPO) u ukupnom ćelijskom ekstraktu moždanog tkiva. Dobijeni rezultati ukazuju da TiO2/SK NČ ispoljavaju slične efekte kao TiO2 NČ, povećavajući nivo LPO koji može biti uzrok narušene SMF. Sa druge strane, smanjen stepen neurološkog deficita i nivoa oksidativnog stresa nakon TiO2/5- ASK NČ tretmana, mogu se povezati sa povećanjem aktivnosti komponenti antioksidativne zaštite. Stoga, može se pretpostaviti da površinska modifikacija TiO2 NČ sa 5-ASK ima sposobnost ublažavanja štetnih efekata komercijalno dostupnih TiO2 NČ.

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in many daily necessities, including medicine, food/ beverages, and cosmetics. Besides the numerous benefits of TiO2 NPs utilization, their use raises public concerns since humans are exposed to their toxicity. As different alterations could moderate the observed side effects of commercially available bare TiO2 NPs, we investigated whether TiO2/SA NPs (TiO2 NPs surface‑modified with salicylic acid (SA)) impact the bare TiO2 NPs-induced sensory-motor impairments and eye level of 4-hydroxynonenal (HNE) as the final product of lipid peroxidation and indicator of oxidative stress. Our results demonstrate that 14 days following single oral treatment both investigated TiO2 NPs in adult Wistar rats affected neurological functions and promoted oxidative stress to different extents. Namely, the SA modification alleviated TiO2 NPs-induced asymmetry in four limb movement, while the hind limb clasping reflex and spontaneous activity scores were similar between TiO2 groups. In the eye crude membrane fraction of TiO2/SA NPs-treated rats in comparison to animals treated with bare TiO2 NPs, the HNE level was downregulated. Although SA exhibits the ability to reduce some TiO2 NPs toxicity, due to still unknown mechanism of TiO2 and TiO2/SA NPs actions, further studies are required to verify herein presented findings

This work is aimed to characterize the gold complexes using the electron spray ionization (ESI), and atmospheric solids analysis probe (ASAP), tandem quadrupole mass spectrometer (TQD). It is demonstrated here that the use of the ASAP is more suitable than the ESI for a rapid analysis of the gold coatings in the solid and liquid state. The mass spectra indicate that mercaptotriazole and glycine can coordinate with the gold ion and to build complexes such as [Au-2MT-Gly] and [Au-2MT-2Gly].

Progesterone (P4), a naturally occurring gonadal hormone in the brain, and its metabolites, are proposed as potential therapeutic agents in various neurodegenerative animal models given that their neuroprotective properties might be associated with amelioration of oxidative stress. Since P4 actions in rat striatum upon permanent ligation of both common carotid arteries are still ambiguous, the present study aimed to evaluate whether 7 days lasting P4 treatment could modulate the levels of several striatal oxidative stress indicators, including prooxidant/antioxidant balance (PAB), advanced oxidation protein products (AOPP) and products of lipid peroxidation (LPO). For the purpose of the experiment, adult male Wistar rats (n = 12) were divided into 3 groups: sham-operated animals subjected to vehicle (commercial flax oil, 1 mg/kg, s.c., Sham + V), occluded animals treated either with vehicle (2VO + V) or P4 (dissolved in commercial flax oil, 1.7 mg/kg, s.c., 2VO + P4). Rats were sacrificed 4 h following the last treatment1 and striatal synaptosomal fraction was used for further biochemical analyses 2. Our results demonstrate that investigated oxidative stress indicators are affected to the different extents by P4 treatment. Namely, in comparison to the Sham + V group, PAB level was elevated in 2VO + V rats, while in 2VO + P4 animals it was downregulated to the levels observed in the Sham + V group. In parallel, 2VO-induced alteration of AOPP was decreased following P4 treatment whereas LPO level was still slightly elevated. Overall, our findings suggest that P4 might manifest antioxidative features in the striatum of hypoperfused rats.

Recycling of polymer materials is a promising way of plastic waste reduction and production of compounds that reduce oil-based materials dependence. This paper represents synthesis of waste PET-based plasticizer obtained by esterification of PET depolymerization products (glycolisate) and levulinic (bio-renewable chemical). Depolymerization of the waste PET was performed using diethylene glycol. Morphological and structural analyses confirmed successful depolymerization of waste-PET, as well as esterification of the obtained product with levulinic acid. Good chemical resistance and mechanical properties, e.g. elongation at break of 65% and tensile strength of 50 MPa, of recycled PVC modified with synthesized waste-PET based plasticizer proved that depolymerization and modification of waste-PET represent one efficient solution for plastic waste recycling.