Polyether Compounds Research Articles

Investigation of Host-Guest Inclusion Complex of Mephenesin with α-Cyclodextrin for Innovative Application in Biological System.

The goal of this study was to use coevaporation to look into how polyether compounds like mephenesin (MEP) can be encapsulated into the host molecule α-cyclodextrin's nanohydrophobic cage. Fourier transform infrared spectroscopy (FT-IR) investigations, powder X-ray diffraction (PXRD), and 1H NMR were among the spectroscopic techniques used to describe the inclusion complex. Additionally, Job's plot has been utilized to illustrate how MEP is encapsulated with α-cyclodextrin (α-CD) at a 1:1 molar ratio. The thermal stability of MEP increased after encapsulation according to thermogravimetric analysis (TGA) and differential thermal analysis (DTA) experiments. Mephenesin fits into the cavity of α-cyclodextrin in a 1:1 ratio, as observed by molecular docking for the inclusion complex to find the most appropriate orientation. This observation is further supported by the Job plot. Furthermore, a comparison was carried out based on a cell viability study between the medication and its inclusion complex.

Novel suppressor for damascene copper electrodeposition: Thioether-modified polyether with enhanced adsorption through an adjustable synthesis strategy

The void-free deposition of small-sized and high-aspect ratio interconnect structures requires stronger suppressors than conventional polyethers. In this work, thioether was introduced into polyether to develop novel suppressors with improved adsorption on electrode. The structure of thioether-modified polyether can be easily tailored by choosing proper polyether and thiol compound, thus providing a simple way to regulate electrochemical properties of the suppressor. The electrochemical and copper filling performance related to the molecular structure of novel suppressors were systematically investigated. Thioether-modified polyether, which retains the strong polarizability of typical suppressor and exhibits high resistance to accelerator desorption, can significantly suppress copper deposition on feature sidewalls. This enabled defect-free filling of narrower features at a concentration much lower than the typical usage concentration of suppressor. The modified polyethers with ethylene-propylene-ethylene (EPE) oxide triblock ether chains exhibited higher polarization strength and concentration dependence, facilitating the higher deposition current at the bottom during filling. The length and block ratio of ether chain further influenced the anti-desorption ability of the modified polyether, thereby impacting their suppression on sidewalls, which is crucial in filling process. The convenient structural adjustments for thioether-modified polyether, combined with the derived structure-property relationship, contribute to the development of new suppressors with strong adsorption performance.

Free-Standing, Water-Resistant, and Conductivity-Enhanced PEDOT:PSS Films from In Situ Polymerization of 3-Hydroxymethyl-3-Methyl-Oxetane.

Free-standing films based on conducting polymers, such as poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS), offer many benefits over traditional metal electrodes for applications in flexible electronics. However, to ensure structural integrity when contacting aqueous environments and high levels of electrical conductivity, solution-processed polymers require additives that act as crosslinking agents and conductivity enhancers. In this work, a new approach is presented to fabricate water-resistant free-standing films of PEDOT:PSS and simultaneously increase their conductivity, using an oxetane compound as an additive. It is shown that at moderate temperatures, oxetane polymerizes within the PEDOT:PSS acidic medium, forming hydroxymethyl-substituted polyether compounds that form a network upon crosslinking with PSS. The polymer composite films show self-sustainability, structural stability in aqueous environments, and enhanced conductivity. Finally, the potential of the free-standing films as health-monitoring electrodes, specifically for human electrocardiography, is explored.

3-oxetanylmethanol as additive to PEDOT:PSS for improved conductivity and water-resistance and applications in ink-jet printed electrochemical transistors

3-oxetanylmethanol is used as additive to poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) water dispersions and the properties of thin films, prepared by spin-coating and ink-jet printing, either on glass or flexible polyethylene terephthalate (PET) substrates, are investigated. 1H NMR studies revealed that 3-oxetanylmethanol is reactive within the PEDOT:PSS medium during the film drying step at 120 °C, to form polyether compounds. Chemical cross-linking established through the esterification reaction of pendant hydroxyl groups in polyether chains, resulting from the 3-oxetanylmethanol in situ polymerization, and sulfonate groups from PSS, is also identified by the 1H NMR studies. Spin-cast films prepared from this formulation on either glass or PET exhibited electrical conductivity enhanced by more than two orders of magnitude, when compared to films obtained with the pristine PEDOT:PSS dispersion, reaching maximum values of around 596 and 682 Scm−1 for films on glass and PET, respectively, together with improved water-resistance. Atomic force microscopy and Raman spectroscopic studies, indicating that PEDOT chains are organized in more ordered domains in the films of the oxetane-based formulations, suggest that the polyether compounds modify the PEDOT:PSS phase segregation and promote charge transport across conducting PEDOT segments. Subsequently, improved conductivities and stability were also found for films prepared by high-resolution ink-jet printing of the formulations that led to the most conductive spin coated films. The potential application of the new ink formulations in printed electrodes interfacing aqueous media was assessed by ink-jet printing PEDOT-based electrochemical transistors operating with aqueous KCl electrolyte.

Intravenous Polyethylene Glycol Alleviates Intestinal Ischemia-Reperfusion Injury in a Rodent Model

Intestinal ischemia-reperfusion injury (IRI) is a common clinical entity, and its outcome is unpredictable due to the triad of inflammation, increased permeability and bacterial translocation. Polyethylene glycol (PEG) is a polyether compound that is extensively used in pharmacology as an excipient in various products. More recently, this class of products have shown to have potent anti-inflammatory, anti-apoptotic, immunosuppressive and cell-membrane-stabilizing properties. However, its effects on the outcome after intestinal IRI have not yet been investigated. We hypothesized that PEG administration would reduce the effects of intestinal IRI in rodents. In a previously described rat model of severe IRI (45 min of ischemia followed by 60 min of reperfusion), we evaluated the effect of IV PEG administration at different doses (50 and 100 mg/kg) before and after the onset of ischemia. In comparison to control animals, PEG administration stabilized the endothelial glycocalyx, leading to reduced reperfusion edema, bacterial translocation and inflammatory reaction as well as improved 7-day survival. These effects were seen both in a pretreatment and in a treatment setting. The fact that this product is readily available and safe should encourage further clinical investigations in settings of intestinal IRI, organ preservation and transplantation.

Dual targeting salinomycin-loaded smart nanomicelles for enhanced accumulation and therapeutic outcome in breast cancer

Salinomycin is a polyether compound that exhibits strong anticancer activity and is known as the cancer stem cell inhibitor that reached clinical testing. The rapid elimination of nanoparticles from the bloodstream by the mononuclear phagocyte system (MPS), the liver, and the spleen, accompanied by protein corona (PC) formation, restricts in vivo delivery of nanoparticles in the tumor microenvironment (TME). The DNA aptamer (TA1) that successfully targets the overexpressed CD44 antigen on the surface of breast cancer cells suffers strongly from PC formation in vivo. Thus, cleverly designed targeted strategies that lead to the accumulation of nanoparticles in the tumor become a top priority in the drug delivery field. In this work, dual redox/pH-sensitive poly (β-amino ester) copolymeric micelles modified with CSRLSLPGSSSKpalmSSS peptide and TA1 aptamer, as dual targeting ligands, were synthesized and fully characterized by physico-chemical methods. These biologically transformable stealth NPs were altered into the two ligand-capped (SRL-2 and TA1) NPs for synergistic targeting of the 4T1 breast cancer model after exposure to the TME. The PC formation was reduced sharply in Raw 264.7 cells by increasing the CSRLSLPGSSSKpalmSSS peptide concentration in modified micelles. Surprisingly, in vitro and in vivo biodistribution findings showed that dual targeted micelle accumulation in the TME of 4T1 breast cancer model was significantly higher than that of single modified formulation, along with deep penetration 24 h after intraperitoneal injection. Also, an in vivo treatment study showed remarkable tumor growth inhibition in 4T1 tumor-bearing Balb/c mice, compared to different formulations, with a 10% lower therapeutic dose (TD) of SAL that was confirmed by hematoxylin and eosin staining (H&E) and the TUNEL assay. Overall, in this study, we developed smart transformable NPs in which the body's own engineering systems alter their biological identity, which resulted in a reduction in therapeutic dosage along with a lowered off-target effect.

Pressure effects on the resonant attenuation of soft porous beads-based materials for underwater acoustics

Dedicated coating materials for anechoism and furtivity in underwater acoustics must exhibit a strong reliability regarding their mechanical resistance to hydrostatic pressure. Soft porous materials, especially, a distribution of soft porous beads within a polyurethane matrix, have been previously proposed as an acoustic insulator device. The purpose of the present letter is to investigate the attenuation efficiency of soft porous silicone beads-based materials while being exposed to uniaxial loads mimicking hydrostatic pressures encountered in underwater acoustics. The acoustic performance of this locally resonant material is then compared to the classical coating technology using micro-balloons. The use of an adapted surfactant (a silicone alkyl polyether compound) in the fabrication process of the soft porous silicone-based beads, obtained through an emulsion templating process, leads to particles exhibiting an open porosity. The (resonant) attenuation of the soft porous beads-based material remains greater than the micro-balloons-based material until several bars. Above this critical resilience value, the mechanical stress irreversibly damages the soft porous beads.

Gambierone and Sodium Channel Specific Bioactivity Are Associated with the Extracellular Metabolite Pool of the Marine Dinoflagellate Coolia palmyrensis.

Tropical epibenthic dinoflagellate communities produce a plethora of bioactive secondary metabolites, including the toxins ciguatoxins (CTXs) and potentially gambierones, that can contaminate fishes, leading to ciguatera poisoning (CP) when consumed by humans. Many studies have assessed the cellular toxicity of causative dinoflagellate species to better understand the dynamics of CP outbreaks. However, few studies have explored extracellular toxin pools which may also enter the food web, including through alternative and unanticipated routes of exposure. Additionally, the extracellular exhibition of toxins would suggest an ecological function and may prove important to the ecology of the CP-associated dinoflagellate species. In this study, semi-purified extracts obtained from the media of a Coolia palmyrensis strain (DISL57) isolated from the U.S. Virgin Islands were assessed for bioactivity via a sodium channel specific mouse neuroblastoma cell viability assay and associated metabolites evaluated by targeted and non-targeted liquid chromatography tandem and high-resolution mass spectrometry. We found that extracts of C. palmyrensis media exhibit both veratrine enhancing bioactivity and non-specific bioactivity. LC-HR-MS analysis of the same extract fractions identified gambierone and multiple undescribed peaks with mass spectral characteristics suggestive of structural similarities to polyether compounds. These findings implicate C. palmyrensis as a potential contributor to CP and highlight extracellular toxin pools as a potentially significant source of toxins that may enter the food web through multiple exposure pathways.

Polyethylene Glycol 20k. Does It Fluoresce?

Polyethylene glycol (PEG) is a polyether compound commonly used in biological research and medicine because it is biologically inert. This simple polymer exists in variable chain lengths (and molecular weights). As they are devoid of any contiguous π-system, PEGs are expected to lack fluorescence properties. However, recent studies suggested the occurrence of fluorescence properties in non-traditional fluorophores like PEGs. Herein, a thorough investigation has been conducted to explore if PEG 20k fluoresces. Results of this combined experimental and computational study suggested that although PEG 20k could exhibit "through-space" delocalization of lone pairs of electrons in aggregates/clusters, formed via intermolecular and intramolecular interactions, the actual contributor of fluorescence between 300 and 400 nm is the stabilizer molecule, i.e., 3-tert-butyl-4-hydroxyanisole present in the commercially available PEG 20k. Therefore, the reported fluorescence properties of PEG should be taken with a grain of salt, warranting further investigation.

Rediscovery of Tetronomycin as a Broad-Spectrum and Potent Antibiotic against Drug-Resistant Gram-Positive Bacteria.

Tetronomycin (1), first isolated from a cultured broth of Streptomyces sp. by Juslen et al. in 1974, is a polycyclic polyether compound. However, the biological activity of 1 has not been thoroughly examined. In this study, we found that 1 exhibits more potent antibacterial activity than two well-known antibacterial drugs (vancomycin and linezolid) and is effective against several drug-resistant clinical isolates including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. Furthermore, we reassigned the 13C NMR spectra of 1 and performed a preliminary structure-activity relationship study of 1 to synthesize a chemical probe for target identification, which implied different targets based on its ionophore activity.

Investigation of anti-PEG antibody response to PEG-containing cosmetic products in mice

Polyethylene glycol (PEG), a polyether compound, is available in molecular weights from ∼300g/mol to ∼10,000,000g/mol. In the molecular weight range of ∼750 to ∼5000, PEG is commonly used in bioconjugation technology and nano-formulations to improve the circulation half-life of the formulations and increase their stability. In cosmetics, lower molecular weight PEG compounds such as PEG 60 or PEG 100 are widely used as emulsifiers and skin penetration enhancers. PEG polymers are generally recognized as biologically inert and non-immunogenic. However, it is recently reported that the "pre-existing" anti-PEG antibodies have been detected in high percentages of healthy individuals who have never received treatment with parenteral PEGylated formulations. To the best of our knowledge, we are the first to attempt to find an explanation for the source of pre-existing anti-PEG antibodies in healthy individuals. In a murine study, we demonstrated that topically applied PEG derivatives, present in two commercially available cosmetic products, could efficiently penetrate the stratum corneum and reach the systemic circulation. The skin penetration of PEG derivatives was further enhanced in injured or otherwise compromised skin. Daily application of cosmetic PEG derivatives primed the immune system, inducing anti-PEG IgM production. Anti-PEG IgM was detected by Day 14 in mice with normal skin, while anti-PEG IgM was detected as early as day 7 in mice with compromised skin. In addition, in mice with pre-induced circulating levels of anti-PEG IgM, topically applied PEG derivatives from cosmetic products appeared to bind to the pre-induced anti-PEG IgM, lowering blood levels. Current results indicate that PEG derivatives in cosmetic products may be an important contributor to the source of the "pre-existing" anti-PEG antibodies that have been detected in healthy individuals.

Potential of polyether ionophore compounds as antimalarials through inhibition on Plasmodium falciparum glutathione S-transferase by molecular docking studies

Contexto: La malaria sigue siendo un grave problema sanitario mundial debido al desarrollo de resistencia a los fármacos. Es necesario encontrar nuevos fármacos con mecanismos renovables que sean eficaces para matar a los parásitos. Nuestra investigación anterior ha analizado más de un compuesto del grupo ionóforo poliéter en el extracto de acetato de etilo de Streptomyces hygroscopicus subsp. hygroscopicus. Se sabe que el poliéter ionóforo tiene un mecanismo de acción similar al de la cloroquina, que es potente inhibidor de gutatión S-transferasa de Plasmodiun falciparum (PfGST). Objetivos: Evaluar el efecto potencial del poliéter ionóforo hacia la PfGST como proteína diana a través del acoplamiento molecular. Métodos: PfGST se obtuvo del Banco de Datos de Proteínas. Los ligandos de prueba (poliéter ionóforo) y los ligandos de control (cloroquina) se obtuvieron de PubChem. El análisis farmacocinético se realizó con SwissADME, el acoplamiento molecular con PyRx 0.9, la visualización con LigPlot y PyMOL, y la dinámica molecular con YASARA para la mejor actividad del ligando. Resultados: La lenoremycina tuvo la mayor afinidad de unión a PfGST (-8,53 kcal/mol) entre otros poliéteres ionóforos, y la nigericina tuvo la mejor unión de residuos con hidrófobos e hidrógenos con una afinidad de unión de -8,25 kcal/mol en comparación con el complejo de cloroquina en el acoplamiento molecular y la simulación dinámica molecular. Conclusiones: El ionóforo poliéter podría servir como agente antimalárico mejor que la cloroquina, siendo la nigericina el mejor candidato para inhibir el PfGST en comparación con otros ionóforos poliéter.

Plastic and Placenta: Identification of Polyethylene Glycol (PEG) Compounds in the Human Placenta by HPLC-MS/MS System.

The placenta is a crucial interface between the fetus and the maternal environment. It allows for nutrient absorption, thermal regulation, waste elimination, and gas exchange through the mother's blood supply. Furthermore, the placenta determines important adjustments and epigenetic modifications that can change the phenotypic expression of the individual even long after birth. Polyethylene glycol (PEG) is a polyether compound derived from petroleum with many applications, from medicine to industrial manufacturing. In this study, for the first time, an integration of ultra-high-performance liquid chromatography (UHPLC) coupled with mass spectrometry (MS) was used to detect suites of PEG compounds in human placenta samples, collected from 12 placentas, originating from physiological pregnancy. In 10 placentas, we identified fragments of PEG in both chorioamniotic membranes and placental cotyledons, for a total of 36 samples.

Synthesis of multifunctional crown ether covalent organic nanospheres as stationary phase for capillary electrochromatography

Crown ethers are macrocyclic polyether compounds containing multiple -oxo-methylene-structural units, which are often used for recognition of metal ions and ammonium ions. Inspired by the molecular design of rotaxanes, a novel covalent organic nanospheres material (CON ADBC-Tp) constructed by 4,4′-diaminodibenzo-18-crown-6 (ADBC) and 2,4,6-triformylphloroglucinol (Tp) was rationally designed as stationary phase for the separation of compounds containing imidazole structure. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were carried out to confirm the morphology and composition of ADBC-Tp and ADBC-Tp modified capillary column. Thanks to the introduction of crown ether building ligands, the prepared capillary column exhibited excellent separation selectivity towards protonated imidazole structure, with benzimidazole and its 2-substituted derivatives as modal analytes. Moreover, separation of fungicides, nucleobases, short peptides and sulfanilamides were achieved on ADBC-Tp@capillary. The multifunctional ADBC-Tp@capillary with satisfactory reproducibility and stability gives great promise for separation science.

Evaluating Age and Growth Relationship to Ciguatoxicity in Five Coral Reef Fish Species from French Polynesia

Ciguatera poisoning (CP) results from the consumption of coral reef fish or marine invertebrates contaminated with potent marine polyether compounds, namely ciguatoxins. In French Polynesia, 220 fish specimens belonging to parrotfish (Chlorurus microrhinos, Scarus forsteni, and Scarus ghobban), surgeonfish (Naso lituratus), and groupers (Epinephelus polyphekadion) were collected from two sites with contrasted risk of CP, i.e., Kaukura Atoll versus Mangareva Island. Fish age and growth were assessed from otoliths’ yearly increments and their ciguatoxic status (negative, suspect, or positive) was evaluated by neuroblastoma cell-based assay. Using permutational multivariate analyses of variance, no significant differences in size and weight were found between negative and suspect specimens while positive specimens showed significantly greater size and weight particularly for E. polyphekadion and S. ghobban. However, eating small or low-weight specimens remains risky due to the high variability in size and weight of positive fish. Overall, no relationship could be evidenced between fish ciguatoxicity and age and growth characteristics. In conclusion, size, weight, age, and growth are not reliable determinants of fish ciguatoxicity which appears to be rather species and/or site-specific, although larger fish pose an increased risk of poisoning. Such findings have important implications in current CP risk management programs.

Undescribed polyether ionophores from Streptomyces cacaoi and their antibacterial and antiproliferative activities

Polyether ionophores represent a large group of naturally occurring compounds mainly produced by Streptomyces species. With previously proven varieties of bioactivity including antibacterial, antifungal, antiparasitic, antiviral and anti-tumor effects, the discovery of undescribed polyethers leading to development of efficient therapeutics has become important. As part of our research on polyether-rich Streptomyces cacaoi, we previously performed modification studies on fermentation conditions to induce synthesis of specialized metabolites. Here, we report four undescribed and nine known polyether compounds from S. cacaoi grown in optimized conditions. Antimicrobial activity assays revealed that four compounds, including the undescribed (6), showed strong inhibitory effects over both Bacillus subtilis and methicillin-resistant Staphylococcus aureus (MRSA) growth. Additionally, K41-A and its C15-demethoxy derivative exhibited significant cytotoxicity. These results signified that selectivity of C15-demethoxy K41-A towards cancer cells was higher than K41-A, which prompted us to conduct mechanistic experiments. These studies showed that this uninvestigated compound acts as a multitarget compound by inhibiting autophagic flux, inducing reactive oxygen species formation, abolishing proteasome activity, and stimulating ER stress. Consequently, the optimized fermentation conditions of S. cacaoi led to the isolation of undescribed and known polyethers displaying promising activities.

Allergy to polyethylene glycol/macrogol following dental surgery

AbstractBackgroundPolyethylene glycols (PEGs) are polyether compounds widely used as excipients within the pharmaceutical industry. PEG allergy is rare but increasingly reported as an unexpected cause for anaphylaxis including to the mRNA COVID‐19 vaccines. Presentation is usually with anaphylaxis to multiple unrelated drugs/products.Case PresentationWe report a case of a 25‐year‐old man who had allergic reactions following root canal treatment with Odontopaste and a second reaction after a single dose of phenoxymethylpenicillin (PEG 6000). Allergy investigations confirmed PEG allergy.ConclusionAll dental healthcare practitioners should be aware of a potentially life‐threatening allergy to PEG, an excipient often overlooked during investigation of anaphylaxis.

Fast pyrolysis of polyurethanes and polyisocyanurate with and without flame retardant: Compounds of interest for chemical recycling

To date, the recycling of polyurethane (PU) and polyisocyanurate (PIR) waste still poses a significant problem. Within this contribution, the thermal degradation of high-resilient ether PU, semirigid PU, rigid PU, and (PIR) with and without TCPP flame retardant was studied at different temperatures to identify and quantify the main products. For this, a tandem micropyrolyzer coupled to GC × GC with FID and ToF-MS detectors was used, and the yield volatiles, light gases, and residue was quantified. The volatile pyrolysis vapours obtained from pyrolyzing high-resilient ether PU and semirigid PU at 600 °C were very similar, and the main products obtained were ethylene and propylene (combined yield of ~13 wt%), ~16 wt% of various oxygenates, and 4–6 wt% organic nitrogen compounds. The oxygenates included mostly poly-ether type compounds with varying molecular weight, and these are attributed to the decomposition of the polyol chains forming the soft segments of the polymer. The main semi-volatile nitrogen compound was 4,4′-methylenedianiline, attributed to the decomposition of the hard segments in the PU structure synthesized from MDI. The pyrolysis vapours from rigid PU contained several ether-type compounds and high yields of heteroatom-free monoaromatics—in particular styrene. The PIRs were more difficult to decompose and volatilize than the PUs, resulting in ~20 wt% higher residue yields. The charring propensity was even higher in the absence of a flame retardant in the formulation. Pyrolysis of TCPP-containing PIR produced Cl-containing pyrolysis vapours such as allyl chlorides. While the yield of H2O was comparable for the different PUs and PIR, pyrolysis of PIR produced higher yields of CO2 and less CO compared to the different PUs. The use of catalysts can help to convert PU waste pyrolysis vapours more efficiently to desirable chemicals.

An extensive investigation on supramolecular assembly of a drug (MEP) with βCD for innovative applications

Herein, we report the experimental study emerged on the encapsulation of polyether compounds such as mephenesin (MEP) into the nano hydrophobic cage of β-cyclodextrin as host molecule. The commonly known co-precipitation method was followed to prepare inclusion complex (IC) by molar ratio 1:1. Different spectrometric techniques e.g. transform infrared spectroscopy (FTIR), DSC, TGA, DTA and scanning electron microscope (SEM) indicated molecular interactions between β-CD and MEP. UV–visible titration predicts the binding constant for βCD and MEP in solution state around 2.1 × 103 M−1. The formation of the inclusion complex has been predicted by slight shifts in the FTIR as well as 1H NMR spectrum. Job plot and ESI-MS spectra showed that 1:1 inclusion complex has been formed. Molecular docking study unveils the inclusion mechanism which is well supported with the experimental data. In addition, UV–visible spectroscopic study predicts the binding interaction between mephenesin with amino acid residues of BSA and DNA.

Expert Consensus Statement from the American Society of Echocardiography on Hypersensitivity Reactions to Ultrasound Enhancing Agents in Patients with Allergy to Polyethylene Glycol

Expert Consensus Statement from the American Society of Echocardiography on Hypersensitivity Reactions to Ultrasound Enhancing Agents in Patients with Allergy to Polyethylene Glycol