Strong Acidic Conditions Research Articles

Effect of Surface Pretreatments on the Formation of Zr‐Based Conversion Layers on Zn–Al–Mg Alloy‐Coated Steel

ABSTRACTZr‐based conversion coatings represent an environmentally conscious alternative to traditional phosphating and chromating in the automotive industry. In this study, we employ XPS and LEIS to investigate the formation of Zr‐conversion layers on Zn–Mg–Al alloy after alkaline and acidic model pretreatments. On alkaline pretreated surfaces, a Zr‐oxide/oxyfluoride layer and an underlying Mg–Al–fluoride layer are formed, whereas acidic pretreatment results in only an oxidic layer. The thickness of the Zr‐layer depends on pretreatment pH and immersion time. Acidic treatment achieves an approximately 23 nm‐thick Zr‐oxide/oxyfluoride layer after 1 min, while prolonged treatment increases the thickness of the oxidic layer for strong alkaline and acidic conditions. Mild alkaline pretreatments, however, do not benefit from extended immersion. F‐induced corrosion pits are observed after mild alkaline treatment. The strong alkaline pretreatment proved to be the most efficient in creating a double‐layered Zr‐conversion coating with increased oxidic layer thickness over time.

Effect of pH on the extraction and stability of anthocyanins from jaboticaba berries

Anthocyanins are water-soluble plant pigments whose stability is strongly influenced by pH. The effects of pH on the extraction of anthocyanins from jaboticaba berries were investigated using an ultrasound-assisted method. A strong acidic condition (pH 1.5) was found to produce a higher yield and monomeric anthocyanin content, particularly at longer ultrasonication time (30 min). The small pH increment of 0.3 over 2 weeks following a zero-order kinetic model. The monomeric anthocyanins increased more rapidly in refrigerated samples, with a kinetic constant of 0.017 mg/g per day, following a first-order kinetic model. Anthocyanins underwent a two-step mechanism in which colour intensity was reduced significantly in the first week, followed by lightness reduction in the second week. The decline of browning index suggested enzymatic reactions contributed to colour darkening. Negative activation energy reflected the complexity of biochemical reactions, possibly involving a balance of reversible and irreversible processes where the reaction equilibrium was influenced by temperature.

Demonstration of Scalable Water Splitting into H2 and O2 by a Flow-Type Photocatalysis-Electrolysis Hybrid System Using a Highly Stable Photocatalyst.

Water splitting via a photocatalysis-electrolysis hybrid system has been investigated as a potentially scalable and economically feasible means of producing renewable H2. However, there are no reports demonstrating a scalable system for stoichiometric water splitting using an efficient and stable photocatalyst, and the key operating conditions for efficiently driving the entire system have not been established. Herein, we address the issues required to efficiently drive the entire system of a Cs+, Fe2+, and H+ ion-modified WO3 (denoted as H-Fe-Cs-WO3) photocatalyst fixed reactor combined with a polymer electrolyte membrane (PEM)-type electrolyzer. In electrochemical H2 production using Fe2+, the current density improved as the concentration of both H+ and Fe2+ increased, and we determined the optimum conditions for a hybrid system using high concentrations of HClO4 and Fe(ClO4)3, which differ from those reported for photocatalysis alone. No performance deterioration of the H-Fe-Cs-WO3 photocatalyst was observed even after light irradiation for more than 10 000 h under strong acidic conditions. The accumulated Fe2+ ions were extremely stable and did not oxidize even when exposed to air for more than two months. As for the stepwise operation that takes advantage of the characteristics of the hybrid system, the contribution factor of the photocatalyst in the photocatalysis-electrolysis hybrid system for H2 evolution (CP@STHap) under an applied bias was estimated to be 0.24%, which is a value comparable to that of the solar-to-chemical (STC) conversion efficiency (0.31%). The efficiency difference (0.07%) corresponds to the overpotential of the electrolytic reaction and indicates that water splitting via the photocatalysis-electrolysis hybrid system proceeds efficiently at a small overpotential of 0.06 V (∼11.6 kJ mol-1).

Characterization of groundwater and cores in the decommissioned acid in-situ leach uranium mining area: Enlightenment for uranium contaminated groundwater remediation

Acid In-situ Leach (AISL) is predominant technique for uranium mining in sandstone-type deposits in China. However, its impact on the biogeochemical conditions of sandstone uranium deposits remains poorly understood. In this study, we performed detailed physicochemical analyses of groundwater, as well as mineralogical, chemical and biogeochemical analyses of cores collected from the decommissioned AISL uranium mining area in the Yili Basin, northwestern China. After AISL uranium mining, U(IV) minerals and pyrite were oxidized and dissolved. The groundwater in the AISL-mined uranium deposit (AISLMUD) became highly acidic and oxidizing after mining ceased. Pyrite, which significantly influences the migration, transformation and immobilization of uranium, was minimal in all cores. Kaolinite, chlorite, quartz, K-feldspar, albite and muscovite exhibited poor adsorption capacity of U(VI) under strong acid conditions. The AISLMUD demonstrated limited capacity to retain U(VI) under highly acid conditions. Furthermore, high-throughput sequencing analysis revealed a substantial reduction in both microbial diversity and abundance in the cores. Microorganisms associated with U(VI) reduction were detected in the cores, with the exception of sulfate reduction bacteria. However, the results of microbial incubation showed that U(VI) reduction-related bacteria could not be in-situ activated by the addition of electron donors under the environmental stresses induced by prolonged acid in-situ leaching. These findings cast doubt on the feasibility of remediating uranium-contaminated groundwater with a pH below 3 through in-situ activation of U(VI) reduction-related bacteria. This research holds significant implications for evaluating the suitability of existing methods and developing new approaches for the restoration of AISLMUD.

Synthesis, Material Properties, and Organocatalytic Performance of Hypervalent Iodine(III)-Oxidants in Core–Shell-Structured Magnetic Nanoparticles

Magnetic nanoparticles (MNPs) based on magnetite (Fe3O4) are attractive catalyst supports due to their high surface area, easy preparation, and facile separation, but they lack stability in acidic reaction media. The search for MNPs stable in oxidative acidic reaction media is a necessity if one wants to combine the advantages of MNPs as catalyst supports with those of iodine(III) reagents being environmentally benign oxidizers. In this work, immobilized iodophenyl organocatalysts on magnetite support (IMNPs) were obtained by crossed-linking polymerization of 4-iodostyrene with 1,4-divinylbenzene in the presence of MNPs. The obtained IMNPs were characterized by TGA, IR, SEM, STEM, and HAADF to gain information on catalyst morphology, average particle size (80–100 nm), and their core–shell structure. IMNP-catalysts tested in (i) the α-tosyloxylation of propiophenone 1 with meta-chloroperbenzoic acid (m-CPBA) and (ii) in the oxidation of 9,10-dimethoxyanthracene 3 with Oxone® as the side-oxidant showed a similar performance as reactions using stoichiometric amounts of iodophenyl. The developed IMNPs withstand strong acidic conditions and serve as reusable organocatalysts. They are recyclable up to four times for repeated organocatalytic oxidations with rates of recovery of 80–92%. This is the first example of a—(4-iodophenyl)polystyrene shell—magnetite core-structured organocatalyst withstanding strong acidic reaction conditions.

Extraction, Purification and Characterization of Poly Phenol Oxidase from Potato and Apple and Inhibition of Enzymatic Browning

The purpose of this study was to determine the optimum conditions for the extraction of polyphenol oxidase (PPO) from potato and apple. PPO is found in a variety of fruits and vegetables and is the enzyme that causes browning reactions when handling damaged cells. At 405 nm, the enzyme activity was determined using spectrophotometry. PPO was researched to stop potato and apple from browning, which reduces their marketability. The outcomes showed that using an extraction buffer containing phosphate buffer (0.05 M, pH 6.6) was the optimum condition for the extraction of polyphenol oxidase from potato and apple. In addition, the results showed that as the temperature increased, the (PPO) activity increased, and the activity reached its peak at a temperature of 35 ͦC. The optimum pH value of (PPO) activity was 6.5 and we observed during the research that (PPO) decreased in strong acid condition and alkaline environments. Moreover, the results showed that the highest activity of polyphenol oxidase enzyme extracted from apple and potato was by using (O-dihydroxybenzene) as a substrate. As the concentration of the substrate increased, the (PPO) activity increased, reaching the optimum substrate concentration of 0.8%, and then its activity decreased. Also, we found that when using ascorbic acid, citric acid, and Na2SO3 as inhibitors, the activity of the polyphenol oxidase enzyme decreased with an increase in the concentration of ascorbic acid, citric acid, and Na2SO3. Sodium thiosulfate, 0.01 M ascorbic acid and 0.5% polyethylene glycol were extracted with an extraction ratio of 1:4 (w/v) for three minutes by using a blender. The purpose of study was to determine the optimum conditions for polyphenol oxidase extraction from potato and apple.

Performance and mechanism of amino-functionalized hydroxyapatite for uranium removal from strong acidity uranium wastewater

The extraction of uranium generates substantial volumes of acidic wastewater loaded with uranium, thereby posing imminent threats to ecological systems and human wellbeing. Consequently, the development of highly effective adsorbent materials for uranium sequestration under strong acidic conditions has become paramount. The amino group contains a lone pair of electrons and is a highly reactive nucleophilic group with a strong affinity for uranium. Herein, we report the amino-functionalized materials (HAP-L-1NH2, HAP-L-2NH2, and HAP-L-3NH2) derived from sodium citrate-modified hydroxyapatite (HAP-L) through a combination of ultrasonic heating and grafting with varying concentrations of 2-amino-1,3-propanediol. The study delved into their performance and underlying mechanisms for uranium removal from acidic wastewater. The findings indicate that an optimal pH of 3.0 favors uranium adsorption for all the materials, with adsorption equilibrium achieved within 30 min. Their respective maximum uranium adsorption capacities stand at 826.44, 990.09, 1060.21, and 884.95 mg g−1, significantly enhancing the adsorptive prowess of amino-functionalized HAP-L materials. The kinetics and thermodynamics manifest that spontaneous endothermic chemisorption occurs on a homogenous monolayer during the adsorption process. Notably, HAP-L-2NH2 robust resilience to interfering ions and exceptional recyclability. After eight cycles of adsorption-desorption, HAP-L-2NH2 retains a uranium adsorption rate of 93.96 % with a stable chemical structure. Application of HAP-L-2NH2 in treating real-world acidic uranium wastewater led to a notable increase in pH from 2.87 to 3.92 and a substantial reduction in uranium concentration from 0.883 mg L−1 to 0.0104 mg L−1. Uranium removal by HAP-L-2NH2 is primarily governed by ion exchange, electrostatic interaction, and co-precipitation reactions.

Fabricating Polymeric Micelles with Enrichment and Cavity Effect for In Situ Enzyme Imobilization from Natural Biosystems.

Metal-organic frameworks and hydrogen-organic frameworks (MOFs and HOFs) are attractive hosts for enzyme immobilization, but they are limited to immobilizing the purified enzymes, making industrial upscaling unattractive. Herein, aptamer-modified dual thermoresponsive polymeric micelles with switchable self-assembly and core-shell structure are constructed, which enable selective immobilization of trypsin directly from complex biological systems through a cascade operation of separation and immobilization. Their steric self-assembly provides a large amount of adsorption sites on the soluble micellar shell, resulting in high adsorption capacity and excellent selectivity. Meanwhile, their aptamer affinity ligand and cavity maintain the native conformations of trypsin and offer protective effects even in harsh conditions. The maximum adsorption capacity of the polymeric micelles for trypsin was determined to be 197 mg/g at 60 min, superior to those of MOFs and HOFs. 67.2 and 86.6% of its original activity was retained for trypsin immobilized in the cavity under strong alkaline and acidic conditions, respectively.

Highly Stable Perovskite Oxides for Electrocatalytic Acidic NOx− Reduction Streamlining Ammonia Synthesis from Air

AbstractElectrochemical nitrogen oxide ions reduction reaction (NOx−RR) shows great opportunity for ammonia production under ambient conditions. Yet, performing NOx−RR in strong acidic conditions remains challenging due to the corrosion effect on the catalyst and competing hydrogen evolution reactions. Here, we demonstrate a stable La1.5Sr0.5Ni0.5Fe0.5O4 perovskite oxide for the NOx−RR at pH 0, achieving a Faradaic efficiency for ammonia of approaching 100 % at a current density of 2 A cm−2 in a H‐type cell. At industrially relevant current density, the NOx−RR system shows stable cell voltage and Faradaic efficiency for >350 h in membrane electrode assembly (MEA) at pH 0. By integrating the catalyst in a stacked MEA with a series connection, we have successfully obtained a record‐breaking 2.578 g h−1 NH3 production rate at 20 A. This catalyst‘s unique acid‐operability streamlines downstream ammonia utilization for direct ammonium salt production and upstream integration with NOx sources. Techno‐economic and lifecycle assessments reveal substantial economic advantages for this ammonia production strategy, even when coupled with a plasma‐based NOx production system, presenting a sustainable complement to the conventional Haber–Bosch process.

Highly Stable Perovskite Oxides for Electrocatalytic Acidic NOx - Reduction Streamlining Ammonia Synthesis from Air.

Electrochemical nitrogen oxide ions reduction reaction (NOx -RR) shows great opportunity for ammonia production under ambient conditions. Yet, performing NOx -RR in strong acidic conditions remains challenging due to the corrosion effect on the catalyst and competing hydrogen evolution reactions. Here, we demonstrate a stable La1.5Sr0.5Ni0.5Fe0.5O4 perovskite oxide for the NOx -RR at pH 0, achieving a Faradaic efficiency for ammonia of approaching 100 % at a current density of 2 A cm-2 in a H-type cell. At industrially relevant current density, the NOx -RR system shows stable cell voltage and Faradaic efficiency for >350 h in membrane electrode assembly (MEA) at pH 0. By integrating the catalyst in a stacked MEA with a series connection, we have successfully obtained a record-breaking 2.578 g h-1 NH3 production rate at 20 A. This catalyst's unique acid-operability streamlines downstream ammonia utilization for direct ammonium salt production and upstream integration with NOx sources. Techno-economic and lifecycle assessments reveal substantial economic advantages for this ammonia production strategy, even when coupled with a plasma-based NOx production system, presenting a sustainable complement to the conventional Haber-Bosch process.

Germination characteristics associated with nicosulfuron resistance in Amaranthus retroflexus L.

Nicosulfuron-resistant biotype (R) and -sensitive biotype (S) Amaranthus retroflexus L. seeds were subjected to different temperature, light, salt, osmotic potential, pH value and burial depth treatments. The difference in germination response of two populations to the above abiotic environmental factors was used to study the fitness cost of nicosulfuron-resistance evolution in A. retroflexus. The aim is to find a powerful tool for weed control in the presence of evolutionary resistance selection. The results of this experiment showed that the germination rate and germination index in S population were generally higher than that in R population. When the salt stress was 80 mM, the water potential was -0.1 Mpa ~ -0.4 Mpa, and under strong acid and alkali conditions, the germination index in S population was prominently higher than that in R population (p<0.05). The delayed seed germination in R population indicated that its nicosulfuron resistance may be linked to seed biochemical compositions that altered seed germination dynamics. The resistant and sensitive biotype of A. retroflexus had differently favourable adaptability in diverse environments. Salt, osmotic potential and pH value are not the major constraints for A. retroflexus germination, however, A. retroflexus are strongly responsive to temperature, light and burial depth. Considering that seeds of A. retroflexus are unable to reach the soil surface beyond the depth of 6 cm, deep inversion tillage before sowing may be an effective and economical weed management tool for the control of nicosulfuron resistant A. retroflexus.

Isolation and Characterization of Antioxidant Peptides from Dairy Cow (Bos taurus) Placenta and Their Antioxidant Activities.

Our preliminary study identified dairy cow placenta extract (CPE) as a mixture of peptides with potent antioxidant activity both in vivo and in vitro. However, the specific antioxidant peptides (AOPs) responsible for this activity were not yet identified. In the current study, we employed virtual screening and chromatography techniques to isolate two peptides, ANNGKQWAEVF (CP1) and QPGLPGPAG (CP2), from CPE. These peptides were found to be less stable under extreme conditions such as high temperature, strong acid, strong alkali, and simulated digestive conditions. Nevertheless, under normal physiological conditions, both CP1 and CP2 exhibited significant antioxidant properties, including free-radical scavenging, metal chelating, and the inhibition of lipid peroxidation. They also up-regulated the activities of intracellular antioxidant enzymes in response to hydrogen-peroxide-induced oxidative stress, resulting in reduced MDA levels, a decreased expression of the Keap1 gene and protein, and increased levels of the Nrf2 and HO-1 genes and proteins. Furthermore, CP1 demonstrated superior antioxidant activity compared to CP2. These findings suggest that CP1 and CP2 hold potential for mitigating oxidative stress in vitro and highlight the efficacy of virtual screening as a method for isolating AOPs within CPE.

Constrution of Quinazoline-Linked Covalent Organic Frameworks via a Multicomponent Reaction for Photocatalysis.

Quinazoline (Qz)-linked covalent organic frameworks (COFs) have been constructed via a three-component reaction of ortho-acylanilines, benzaldehydes and NH4OAc. The structure of Qz-COFs has been confirmed by solid-state nuclear magnetic resonance spectroscopy, Fourier transform infrared and powder X-ray diffraction patterns. The Qz-COFs possess high chemical stability, showing good endurance to strong acid, strong base, oxidant, reductant and other conditions. Particularly, Qz-COF-3 can catalyze the aerobic photooxidation of toluene and other compounds containing C(sp3)-H bonds.

Bioinspired Diiron Complex with Proton Shuttling and Redox-Active Ligand for Electrocatalytic Hydrogen Evolution.

A μ-oxo diiron complex, featuring the pyridine-2,6-dicarboxamide-based thiazoline-derived redox-active ligand, H2L (H2L = N2,N6-bis(4,5-dihydrothiazol-2-yl)pyridine-2,6-dicarboxamide), was synthesized and thoroughly characterized. [FeIII-(μ-O)-FeIII] showed electrocatalytic hydrogen evolution reaction activity in the presence of different organic acids of varying pKa values in dimethylformamide. Through electrochemical analysis, we found that [FeIII-(μ-O)-FeIII] is a precatalyst that undergoes concerted two-electron reduction to generate an active catalyst. Fourier transform infrared spectrum of reduced species and density functional theory (DFT) investigation indicate that the active catalyst contains a bridged hydroxo unit which serves as a local proton source for the Fe(III) hydride intermediate to release H2. We propose that in this active catalyst, the thiazolinium moiety acts as a proton-transferring group. Additionally, under sufficiently strong acidic conditions, bridged oxygen gets protonated before two-electron reduction. In the presence of exogenous acids of varying strengths, it displays electro-assisted catalytic response at a distinct applied potential. Stepwise electron-transfer and protonation reactions on the metal center and the ligand were studied through DFT to understand the thermodynamically favorable pathways. An ECEC or EECC mechanism is proposed depending on the acid strength and applied potential.

NiFe2O4/N-CNT mediated peroxydisulfate activation via radical and non-radical pathways for water purification

Metal oxide catalysts can significantly enhance the efficiency of the peroxydisulfate (PDS) activation to decompose refractory organic pollutants, and advanced strategies for improving the activation performance of the catalysts include exposing more metal active sites, optimizing the electronic structure, and enhancing cycling stability. Herein, a novel NiFe2O4/N-CNT composite was synthesized by the simple hydrothermal process. Additionally, the performance of the prepared catalysts can be adjusted by varying the content of N-doped precursors. The prepared NiFe2O4/N-CNT nanostructures had excellent activation properties for PDS, leading to sufficient free radicals and non-free radicals to degrade dyes. The system required only 0.07 g·L−1 of catalyst and 0.1 g·L−1 of PDS to degrade 100 mL (0.1 g·L−1) of reactive brilliant blue KN-R, and the degradation rate could reach 93 % within 30 min. The pH range was also wider, with excellent degradation under strong acidic conditions (pH=1). Moreover, it was highly adaptable to the common anions (Cl-, NO3-) and natural organic humic acid (HA) in the water body. This study expands the idea of the activation mechanism of peroxydisulfate (PDS) and successfully prepares catalysts for the effective degradation of organic dyes, showing the promising application of synergistic interaction between radicals and non-radicals in the degradation of persulfate.

A new insight on the corrosion behavior and mechanism of martensitic steel

The corrosion performance of martensitic steel remains a matter of dispute, with no consensus on whether it exhibits heightened or diminished corrosion resistance. In this study, the corrosion behavior and mechanism of martensitic steel were systematically investigated by simulating a cargo oil tank environment. The results indicate that under strong acidic conditions, the corrosion rate of martensite (1.1404 mm/y) is significantly higher than that of ferrite-pearlite (0.7430 mm/y) due to its increased dislocation density and internal stress. Additionally, the presence of high-energy defects provides abundant active sites for the redeposition of Cu-bearing particles, while their uneven distribution further exacerbates corrosion. Therefore, we propose a competitive mechanism that governs the corrosion behavior of martensite, complementing the understanding of its behavior and mechanism.

Synthesis of linear polyesters bearing amino groups via lipase-catalyzed polymerization of N-protected monomer and deprotection

Linear biodegradable polyesters with a controlled number of side chains of amino groups have been synthesized. Such polyesters with a large number of amino side groups can be conjugated with a wide variety of functional molecules to obtain multi-functional biodegradable polyesters. In this study, poly(1,3-propylene-co-2-amino-1,3-propylene) adipate) (P(P-co-AP)A) was synthesized by enzymatic polymerization of divinyl adipate, 1,3-propanediol, and N-Boc-2-amino-1,3-propanediol (BocAPDO), and subsequent deprotection under strong acidic conditions. The mild reaction conditions and the specificity of the enzymatic polymerization could effectively inhibit side reactions, while the protecting groups of the monomers prevented polymer branching from the amino groups. It was found that the introduction rates of BocAPDO in the polymers could be well-controlled as the feeding rates changed from 0 to 100 mol%. After the deprotection and desalting, the ester groups in the main chain gradually converted into amide groups by intramolecular ester aminolysis at room temperature for a few days due to nucleophilic free amino groups. It was also found that the synthesized functional copolymers were all amorphous, since the random component of amino groups disrupted the crystallinity of poly(1,3-propylene adipate) (PPA). The glass transition temperature gradually increased with the increase in the content of 2-amino-1,3-propylene adipate (APA), eventually reaching −0.4 °C at the APA content of 100 mol% due to the intermolecular hydrogen bonding. Moreover, P(P-co-AP)A shows high hygroscopicity, where 3.9 wt% and 8.1 wt% of water were absorbed in the polymers with the APA contents of 50 and 100 mol%, respectively, when left in air at 60–70 % humidity for 6 h. Thus, the hydrophilicity dramatically improved with the increase in the APA content, eventually resulting in the acquisition of water solubility. The model post-polymerization modification using butyric acid was also conducted, and it was confirmed that carboxylic acids could be conjugated to the polymers by simple condensation reaction. Since polymerization of functional monomers is generally susceptible to the polarity of metal catalysts, the mild and selective reaction employed in this study could realize a higher content of various functional groups in the side chains of polyesters leading to a newly designed multi-functional polyester.

In-situ construction of stable and efficient superhydrophobic MOFs-based cellulose paper for oil–water separation

In recent years, separating oil-water mixed pollutants has emerged as an increasingly significant part of sustainable development due to oil-containing wastewater discharged and offshore oil spills. Therefore, developing stable and efficient materials for the separation of oily wastewater has garnered significant attention in current research. Herein, a novel superhydrophobic functionalized MOFs-based cellulose paper (PDMS/UiO-66-NH2@CP) was successfully synthesized by integrating cellulose paper (CP) with UiO-66-NH2 via solvothermal method and further modifying with polydimethylsiloxane (PDMS), which was used as an oil-water separation material to purify oily wastewater. The reaction procedure is facile and simple, and the preparation method is efficient. Notably, the as-synthesized PDMS/UiO-66-NH2@CP showed excellent superhydrophobicity/superlipophilicity, with a water contact angle up to 162° and an oil contact angle (OCA) of approximately 0º, and it can still maintain superhydrophobic stability under strong acid or alkali conditions. Furthermore, the surface of superhydrophobic paper cannot been adhered by dye solution and powder, indicating its good self-cleaning and anti-fouling ability. Moreover, the composite paper displayed exceptional UV blocking property with the ability to block 99% ultraviolet. Attributed to these characteristics, PDMS/UiO-66-NH2@CP as an oil-water separator demonstrated exceptional performance in separating oil-water mixtures and emulsions, achieving efficiencies exceeding 98% and fluxes in the range of 105.26−412.14 L·m-2·h-1. More importantly, it displayed remarkable recyclability and its separation efficiency was still above 98% after 50 cycles. This study not only develops a facile and effective strategy for preparing superhydrophobic papers, but also provides innovative and instructive guidance for developing efficient oil-water separation materials.

Stable Ozonides plus Vitamin E Acetate (Ozoile) for Treatment of Genitourinary Syndrome.

Background and Objectives: Genitourinary syndrome, previously defined as vulvovaginal atrophy, manifests with signs and symptoms deriving from estrogen diminution in the female genitourinary tract. Stable ozonides are derivatives of artemisinin found to be stable against strong basic and acidic conditions. Vitamin E is an important antioxidant diminishing the output of reactive oxygen species in the oxidation of fats and the emanation of free radicals, reducing cellular injury and aging. The primary aim of the present study was to assess the positive effects of an ozonide plus a vitamin E acetate-based compound (Ozoile) on genitourinary syndrome symptom relief after a maximum of 20 days of treatment. Materials and Methods: The inclusion criteria for patients' enrollment were women of child-bearing age or in menopause reporting genitourinary syndrome's related symptoms, such as pain, burning, a bad smell, dyspareunia, dryness, itching, bleeding, and nervousness. The exclusion criteria were Sjogren's syndrome and patients administered retinoic acid, an agent that causes mucosal dryness. Participants completed a questionnaire before and after 20 days of treatment. Results: The incidence of pain decreased from 16.7% to 11.8% (p-value < 0.0001). In addition, the mean symptom intensity decreased from 2.10 to 0.87 (p-value < 0.0001). Dryness was the most frequent pre-treatment symptom and decreased from 85.5% to 53.8% (p-value < 0.0001) (mean: 2.21 vs. 0.90; p-value < 0.0001). Conclusions: Ozoile was effective in reducing most gynecologic symptoms related to genitourinary syndrome. However, further studies are needed to compare its effect with other standards of care.

Novel Imidazole‐based Hydrazonoyl Cyanides and Amidrazones Containing N(N,O)‐Heterocycles: Selective Synthesis, Reaction Mechanisms and Preliminary Anticancer Evaluation

AbstractTwo series of novel hybrid heterocyclic compounds that combine the imidazole ring with bioactive piperidine, morpholine or piperazine heterosystems, through a hydrazone unit, were easily obtained by two competitive pathways. Starting from 5‐amino‐4‐cyanoformimidoyl imidazoles and 1‐aminopiperidine, 4‐aminomorpholine or 1‐amino‐4‐methylpiperazine under mild acidic media led to the selective synthesis of 5‐aminoimidazole 4‐carboxamidrazones, whereas the corresponding 4‐hydrazonoyl cyanide derivatives were obtained under stronger acidic conditions. These highly functionalized imidazoles provide convenient synthetic precursors to a vast array of heterocycles with potential pharmaceutical applications. The reaction mechanisms were elucidated on the basis of experimental assays and in silico calculations. The compounds were screened against colorectal cancer HCT116‐p53 wt cell line, and significant IC50 values of 3.69 μM and 4.83 μM were obtained.