Sample records for alcohol ethylene glycol

  1. Ethylene glycol poisoning


    ... attempt or as a substitute for drinking alcohol (ethanol). This article is for information only. Do NOT ... attempt or as a substitute for drinking alcohol (ethanol). Ethylene glycol is found in many household products, ...

  2. Ethylene glycol

    Integrated Risk Information System (IRIS)

    Ethylene glycol ; CASRN 107 - 21 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  3. Interstellar Antifreeze: Ethylene Glycol

    NASA Astrophysics Data System (ADS)

    Hollis, J. M.; Lovas, F. J.; Jewell, P. R.; Coudert, L. H.


    Interstellar ethylene glycol (HOCH2CH2OH) has been detected in emission toward the Galactic center source Sagittarius B2(N-LMH) by means of several millimeter-wave rotational torsional transitions of its lowest energy conformer. The types and kinds of molecules found to date in interstellar clouds suggest a chemistry that favors aldehydes and their corresponding reduced alcohols-e.g., formaldehyde (H2CO)/methanol (CH3OH), acetaldehyde (CH3CHO)/ethanol (CH3CH2OH). Similarly, ethylene glycol is the reduced alcohol of glycolaldehyde (CH2OHCHO), which has also been detected toward Sgr B2(N-LMH). While there is no consensus as to how any such large complex molecules are formed in the interstellar clouds, atomic hydrogen (H) and carbon monoxide (CO) could form formaldehyde on grain surfaces, but such surface chemistry beyond that point is uncertain. However, laboratory experiments have shown that the gas-phase reaction of atomic hydrogen (H) and solid-phase CO at 10-20 K can produce formaldehyde and methanol and that alcohols and other complex molecules can be synthesized from cometary ice analogs when subject to ionizing radiation at 15 K. Thus, the presence of aldehyde/reduced alcohol pairs in interstellar clouds implies that such molecules are a product of a low-temperature chemistry on grain surfaces or in grain ice mantles. This work suggests that aldehydes and their corresponding reduced alcohols provide unique observational constraints on the formation of complex interstellar molecules.

  4. Interstellar Antifreeze: Ethylene Glycol

    NASA Technical Reports Server (NTRS)

    Hollis, J. M.; Lovas, F. J.; Jewell, P. R.; Coudert, L. H.


    Interstellar ethylene glycol (HOCH2CH2,OH) has been detected in emission toward the Galactic center source Sagittarius B2(N-LMH) by means of several millimeter-wave rotational torsional transitions of its lowest energy conformer. The types and kinds of molecules found to date in interstellar clouds suggest a chemistry that favors aldehydes and their corresponding reduced alcohols-e.g., formaldehyde (H2CO)/methanol (CH3OH), acetaldehyde (CH3CHO)/ethanol (CH3CH2OH). Similarly, ethylene glycol is the reduced alcohol of glycolaldehyde (CH2OHCHO), which has also been detected toward Sgr B2(N-LMH). While there is no consensus as to how any such large complex molecules are formed in the interstellar clouds, atomic hydrogen (H) and carbon monoxide (CO) could form formaldehyde on grain surfaces, but such surface chemistry beyond that point is uncertain. However, laboratory experiments have shown that the gas-phase reaction of atomic hydrogen (H) and solid-phase CO at 10-20 K can produce formaldehyde and methanol and that alcohols and other complex molecules can be synthesized from cometary ice analogs when subject to ionizing radiation at 15 K. Thus, the presence of aldehyde/ reduced alcohol pairs in interstellar clouds implies that such molecules are a product of a low-temperature chemistry on grain surfaces or in grain ice mantles. This work suggests that aldehydes and their corresponding reduced alcohols provide unique observational constraints on the formation of complex interstellar molecules.

  5. Toxicity of ethylene glycol, diethylene glycol, and propylene glycol to human cells in culture

    SciTech Connect

    Mochida, K.; Gomyoda, M.


    Tissue culture toxicity of various alcohols has been reported by Dillingham who used mouse L cells and Koerker who used mouse neuroblastoma cells. The toxicity of various polyhydric alcohols (ethylene glycol, diethylene glycol and propylene glycol) has apparently not been determined, under conditions of culture. The authors report the toxicity of ethylene glycol, diethylene glycol and propylene glycol and KB cells and the results are compared with previous data obtained using their cell culture system.

  6. Actuator based on sulfonated comb copolymer of poly (ethylene-co-vinyl alcohol) grafted by poly (ethylene glycol)

    NASA Astrophysics Data System (ADS)

    Gong, Guifen; Li, Lei; Zhang, Yujun


    Comb copolymer consisting of poly (ethylene-co-vinyl alcohol) (EVAL) as backbone and poly (ethylene glycol) (PEG) as side chains (EVAL-g-PEG) has been synthesized, then it was sulfonated by 1,3-propane sultone to get the final ionomer (EVAL-g-SPEG), and ionic polymer-metal composite (IPMC) based on EVAL-g-SPEG was prepared through electroless deposition of platinum onto the surfaces of EVAL-g-SPEG membrane. The graft copolymers were characterized with respect to molecular weight using gel permeation chromatography (GPC) and composition using 1H-NMR. The results showed that the No. of PEG graft of the side chains is n=1, 2 and others. Thermal properties were examined by DSC and TG. The melt temperature (T m) and glass transition temperature (T g) of the comb copolymer increase with the increasing length and the number of the side chains. Moreover, the deformation performance of IPMC material was tested and its results show that the starting response voltage of IPMC actuator decreases with the increasing IEC value. On the other hand, the starting response voltage increases with the decreased side chain length. The IPMC with n=2 side chain length of PEG has the maximum tip displacement, and the maximum tip displacement of IPMC membrane generally decreases with the side chain length of EVAL-g-SPEG. This feature may be the reflection of two opposite effects, namely the decreasing ion densities and increasing water sorption of the membrane.

  7. Ethylene glycol, hazardous substance in the household.


    Patocka, Jirí; Hon, Zdenek


    Ethylene glycol is a colorless, odorless, sweet-tasting but poisonous type of alcohol found in many household products. The major use of ethylene glycol is as an antifreeze in, for example, automobiles, in air conditioning systems, in de-icing fluid for windshields, and else. People sometimes drink ethylene glycol mistakenly or on purpose as a substitute for alcohol. Ethylene glycol is toxic, and its drinking should be considered a medical emergency. The major danger from ethylene glycol is following ingestion. Due to its sweet taste, peoples and occasionally animals will sometimes consume large quantities of it if given access to antifreeze. While ethylene glycol itself has a relatively low degree of toxicity, its metabolites are responsible for extensive cellular damage to various tissues, especially the kidneys. This injury is caused by the metabolites, glycolic and oxalic acid and their respective salts, through crystal formation and possibly other mechanisms. Toxic metabolites of ethylene glycol can damage the brain, liver, kidneys, and lungs. The poisoning causes disturbances in the metabolism pathways, including metabolic acidosis. The disturbances may be severe enough to cause profound shock, organ failure, and death. Ethylene glycol is a common poisoning requiring antidotal treatment. PMID:20608228

  8. [Chronic ethylene glycol poisoning].


    Kaiser, W; Steinmauer, H G; Biesenbach, G; Janko, O; Zazgornik, J


    Over a six-week period a 60-year-old patient had several unexplained intoxication-like episodes. He finally had severe abdominal cramps with changes in the level of consciousness and oligoanuric renal failure (creatinine 4.7 mg/dl). The history, marked metabolic acidosis (pH 7.15, HCO3- 2.2 mmol/l, pCO2 6.6 mmHg) as well as raised anion residue (43 mmol/l) and the presence of oxalates in urine suggested poisoning by ethylene glycol contained in antifreeze liquid. Intensive haemodialysis adequately eliminated ethylene glycol and its toxic metabolites (glycol aldehyde, glycolic acid). Renal function returned within 10 days, although the concentrating power of the kidney remained impaired for several weeks because of interstitial nephritis. The intoxication had been caused by a defective heating-pipe system from which the antifreeze had leaked into the hot-water boiler (the patient had habitually prepared hot drinks by using water from the hot-water tap). Gas chromatography demonstrated an ethylene glycol concentration of 21 g per litre of water. PMID:8482240

  9. Oxidation of methanol, ethylene glycol, and isopropanol with human alcohol dehydrogenases and the inhibition by ethanol and 4-methylpyrazole.


    Lee, Shou-Lun; Shih, Hsuan-Ting; Chi, Yu-Chou; Li, Yeung-Pin; Yin, Shih-Jiun


    Human alcohol dehydrogenases (ADHs) include multiple isozymes with broad substrate specificity and ethnic distinct allozymes. ADH catalyzes the rate-limiting step in metabolism of various primary and secondary aliphatic alcohols. The oxidation of common toxic alcohols, that is, methanol, ethylene glycol, and isopropanol by the human ADHs remains poorly understood. Kinetic studies were performed in 0.1M sodium phosphate buffer, at pH 7.5 and 25°C, containing 0.5 mM NAD(+) and varied concentrations of substrate. K(M) values for ethanol with recombinant human class I ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, and ADH1C2, and class II ADH2 and class IV ADH4 were determined to be in the range of 0.12-57 mM, for methanol to be 2.0-3500 mM, for ethylene glycol to be 4.3-2600mM, and for isopropanol to be 0.73-3400 mM. ADH1B3 appeared to be inactive toward ethylene glycol, and ADH2 and ADH4, inactive with methanol. The variations for V(max) for the toxic alcohols were much less than that of the K(M) across the ADH family. 4-Methylpyrazole (4MP) was a competitive inhibitor with respect to ethanol for ADH1A, ADH1B1, ADH1B2, ADH1C1 and ADH1C2, and a noncompetitive inhibitor for ADH1B3, ADH2 and ADH4, with the slope inhibition constants (K(is)) for the whole family being 0.062-960 μM and the intercept inhibition constants (K(ii)), 33-3000 μM. Computer simulation studies using inhibition equations in the presence of alternate substrate ethanol and of dead-end inhibitor 4MP with the determined corresponding kinetic parameters for ADH family, indicate that the oxidation of the toxic alcohols up to 50mM are largely inhibited by 20 mM ethanol or by 50 μM 4MP with some exceptions. The above findings provide an enzymological basis for clinical treatment of methanol and ethylene glycol poisoning by 4MP or ethanol with pharmacogenetic perspectives. PMID:21167143

  10. Metabolic basis of ethylene glycol monobutyl ether (2-butoxyethanol) toxicity: role of alcohol and aldehyde dehydrogenases

    SciTech Connect

    Ghanayem, B.I.; Burka, L.T.; Matthews, H.B.


    2-Butoxyethanol (BE) is a massively produced glycol ether of which more than 230 million pounds was produced in the United States in 1983. It is extensively used in aerosols and cleaning agents intended for household use. This creates a high potential for human exposure during its manufacturing and use. A single exposure of rats to BE causes severe hemolytic anemia accompanied by secondary hemoglobinuria as well as liver and kidney damage. Butoxyacetic acid (BAA) was earlier identified as a urinary metabolite of BE. In addition, we have recently identified two additional urinary metabolites of BE, namely, BE-glucuronide and BE-sulfate conjugates. The current studies were undertaken to investigate the metabolic basis of BE-induced hematotoxicity in male F344 rats. Treatment of rats with pyrazole (alcohol dehydrogenase inhibitor) protected rats against BE-induced hematotoxicity and inhibited BE metabolism to BAA. Pyrazole inhibition of BE metabolism to BAA was accompanied by increased BE metabolism to BE-glucuronide and BE-sulfate as determined by quantitative high-performance liquid chromatography analysis of BE metabolites in urine. There was approximately a 10-fold decrease in the ratio of BAA to BE-glucuronide + BE-sulfate in the urine of rats treated with pyrazole + BE compared to rats treated with BE alone. Pretreatment of rats with cyanamide (aldehyde dehydrogenase inhibitor) also significantly protected rats against BE-induced hematotoxicity and modified BE metabolism in a manner similar to that caused by pyrazole. Administration of equimolar doses of BE, the metabolic intermediate butoxyacetaldehyde, or the ultimate metabolite BAA caused similar hematotoxic effects. Cyanamide also protected rats against butoxyacetaldehyde-induced hematotoxicity.

  11. Colorometric detection of ethylene glycol vapor

    NASA Technical Reports Server (NTRS)

    Helm, C.; Mosier, B.; Verostko, C. E.


    Very low concentrations of ethylene glycol in air or other gases are detected by passing a sample through a glass tube with three partitioned compartments containing reagents which successively convert the ethylene glycol vapor into a colored compound.

  12. Solid state solubility of miconazole in poly[(ethylene glycol)-g-vinyl alcohol] using hot-melt extrusion.


    Litvinov, V M; Guns, S; Adriaensens, P; Scholtens, B J R; Quaedflieg, M P; Carleer, R; Van den Mooter, G


    The use of hot-melt extrusion for preparing homogeneous API-excipient mixtures is studied for miconazole-PEG-g-PVA [poly(ethylene glycol)-poly(vinyl alcohol) graft copolymer] solid dispersions with a 5 cm(3) table-top, twin-screw corotating microcompounder (DSM Xplore). Phase behavior of PEG-g-PVA, miscibility of miconazole in PEG-g-PVA and the partitioning of miconazole between PEG and PVA amorphous phases are characterized using a combination of modulated DSC, XRPD, and solid-state (1)H and (13)C NMR methods. The (1)H NMR transverse magnetization relaxation (T(2) relaxation) method is used to analyze the phase composition and molecular mobility of the copolymer. The T(2) relaxation decay of pure PEG-g-PVA can be described by four T(2) relaxation components in the temperature range studied. PVA crystallinity is not largely affected by hot-melt extrusion and the presence of the drug. Miconazole preferably resides in the PEG amorphous phase, and its molecules are well dispersed in the PEG-g-PVA matrix using hot-melt extrusion mixing. Miconazole forms amorphous nanoclusters whose average size equals approximately 1.6 nm, indicating solid solution formation (molecular level dispersion) of the drug in the polymer. PMID:22905779

  13. Ethylene glycol poisoning in sheep.



    Oxalate toxicity in sheep as a consequence of exposure to ethylene glycol. Chlamydophila abortus infection in a dairy cow. Neosporosis diagnosed in a newborn lamb with deformities. Yersiniosis affecting a 1000-strong goat herd. Porcine reproductive and respiratory syndrome causing blue ears in 14-week-old pigs. Avian tuberculosis diagnosed in an adult Mandarin duck. These are among matters discussed in the Animal and Plant Health Agency's (APHA's) disease surveillance report for January and February 2015. PMID:25977491

  14. The Potential of Photochemical Transition Metal Reactions in Prebiotic Organic Synthesis. I. Observed Conversion of Methanol into Ethylene Glycol as Possible Prototype for Sugar Alcohol Formation

    NASA Astrophysics Data System (ADS)

    Eisch, John J.; Munson, Peter R.; Gitua, John N.


    Photochemical processes involving redox reactions between metal ions and organic substrates possess the versatile potential for having harnessed solar energy for prebiotic organic synthesis. The present study in our Laboratory has shown that ultraviolet irradiation of transition metal ions such as of Ni, Co, Fe, Cu and Ti dissolved in primary or secondary alcohols causes photoreduction of the metal ions with the concomitant oxidation of the alcohol to aldehyde or ketone. An observed accompaniment of this novel `light' reaction has been the known `dark' pinacol reaction, whereby the carbonyl derivative underwent bimolecular coupling to the diol by the photogenerated reduced transition metal reagent. These tandem `light-dark' processes possess the potential for the stepwise synthesis of dimeric 1,2-diols from simpler alcohols under conditions that might have prevailed on the prebiotic earth. Experiments reported here have demonstrated that such a tandem `light-dark' conversion of methanol into ethylene glycol, via formaldehyde, does in fact occur, when nickel(II) acetylacetonate solutions in methanol undergo prolonged irradiation at 185-254 nm. Since ethylene glycol can be considered as the simplest sugar alcohol, these findings may provide novel insight into the prebiotic oligomerization of formaldehyde into higher sugar alcohols or even sugars.

  15. Cooling in the tropics: ethylene glycol overdose.


    Holyoak, Adam L; Fraser, Todd A; Gelperowicz, Pascal


    Ethylene glycol is the active ingredient used in radiator antifreeze. Severe ingestions of ethylene glycol are uncommon in Australia, but if untreated, can result in multiorgan dysfunction, particularly renal failure and cerebral oedema. We report on a patient who consumed a large quantity of ethylene glycol. He was treated with enteral ethanol and went on to make a full recovery, despite an initial moribund state. We briefly review the pathophysiology and current treatment strategies for ethylene glycol intoxication, and discuss issues surrounding enteral versus parenteral ethanol administration. PMID:21355826

  16. Functionalized poly(ethylene glycol)-stabilized water-soluble palladium nanoparticles: property/activity relationship for the aerobic alcohol oxidation in water.


    Feng, Bo; Hou, Zhenshan; Yang, Hanmin; Wang, Xiangrui; Hu, Yu; Li, Huan; Qiao, Yunxiang; Zhao, Xiuge; Huang, Qingfa


    The preparation, characterization, and catalytic properties of water-soluble palladium nanoparticles stabilized by the functionalized-poly(ethylene glycol) as a protective ligand were demonstrated for aerobic oxidation of alcohols in aqueous phase. UV/vis spectra and X-ray photoelectron spectroscopy (XPS) proved that there was an electronic interaction between the bidentate nitrogen ligand and palladium atoms. Transmission electron microscopy and XPS analysis showed that the particle size and surface properties of the generated palladium nanoparticles can be controlled by varying the amount of protective ligand and the kinds of reducing agents. It was found that both the size and surface properties of palladium nanoparticles played very important roles in affecting catalytic performance. The stabilized metallic palladium nanoparticles were proven to be the active centers for benzyl alcohol oxidation in the present system, and the water-soluble Pd nanocatalysts can also be extended to the selective oxidation of various alcohols. PMID:20039597

  17. Influence of poly(ethylene glycol) as pore-generator on morphology and performance of chitosan/poly(vinyl alcohol) membrane adsorbents

    NASA Astrophysics Data System (ADS)

    Salehi, E.; Madaeni, S. S.


    Macroporous chitosan/poly(vinyl alcohol) membrane adsorbents were synthesized by solvent evaporation in the presence of poly(ethylene glycol) which was utilized as porogen. The membranes were applied for Cu(II) ion adsorption from water. SEM, AFM and wettability analyses were performed for membrane characterization. Insertion of poly(ethylene glycol) generated macrovoids in the dense structure of CS/PVA membranes through particulate leaching out mechanism. According to the static adsorption tests, the uptake capacity of the porous membranes is elevated (˜26 mg/g) compared to that of the dense membranes (˜10 mg/g). This phenomenon is attributed to the increase in the density of active sites, water affinity and surface roughness as a result of the porogen effects. The approachability of the ions to the active sites was also affected by these important parameters. Both size and density of the macrovoids increased with increasing PEG content from nil to 5 wt%. Fragility of the resultant porous structures prohibited synthesizing CS/PVA membranes with higher porogen contents. Desorption tests showed that the porous membranes were better regenerated in comparison to the dense membranes using Na2EDTA as eluant. Generally, the results suggested that the CS/PVA membranes, comprising PEG as pore-generator agent, are potential candidates for adsorption and elimination of Cu(II) ions from water.

  18. [Secondary hyperoxaluria and nephrocalcinosis due to ethylene glycol poisoning].


    Monet, C; Richard, E; Missonnier, S; Rebouissoux, L; Llanas, B; Harambat, J


    We report the case of a 3-year-old boy admitted to the pediatric emergency department for ethylene glycol poisoning. During hospitalization, he presented dysuria associated with crystalluria. Blood tests showed metabolic acidosis with an elevated anion gap. A renal ultrasound performed a few weeks later revealed bilateral medullary hyperechogenicity. Urine microscopic analysis showed the presence of weddellite crystals. Secondary nephrocalcinosis due to ethylene glycol intoxication was diagnosed. Hyperhydration and crystallization inhibition by magnesium citrate were initiated. Despite this treatment, persistent weddellite crystals and nephrocalcinosis were seen more than 2years after the intoxication. Ethylene glycol is metabolized in the liver by successive oxidations leading to its final metabolite, oxalic acid. Therefore, metabolic acidosis with an elevated anion gap is usually found following ethylene glycol intoxication. Calcium oxalate crystal deposition may occur in several organs, including the kidneys. The precipitation of calcium oxalate in renal tubules can lead to nephrocalcinosis and acute kidney injury. The long-term renal prognosis is related to chronic tubulointerstitial injury caused by nephrocalcinosis. Treatment of ethylene glycol intoxication is based on specific inhibitors of alcohol dehydrogenase and hemodialysis in the most severe forms, and should be started promptly. PMID:23827374

  19. Ethylene glycol monobutyl ether (EGBE) (2-Butoxyethanol)

    Integrated Risk Information System (IRIS)

    Ethylene glycol monobutyl ether ( EGBE ) ( 2 - Butoxyethanol ) ; CASRN 111 - 76 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I (

  20. Inorganic-organic polymer electrolytes based on poly(vinyl alcohol) and borane/poly(ethylene glycol) monomethyl ether for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Aydın, Hamide; Şenel, Mehmet; Erdemi, Hamit; Baykal, Abdülhadi; Tülü, Metin; Ata, Ali; Bozkurt, Ayhan

    In this study, poly(vinyl alcohol) (PVA) was modified with poly(ethylene glycol) monomethyl ether (PEGME) using borane-tetrahydrofuran (BH 3/THF) complex. Molecular weights of both PVA and PEGME were varied prior to reaction. Boron containing comb-branched copolymers were produced and abbreviated as PVA1PEGMEX and PVA2PEGMEX. Then polymer electrolytes were successfully prepared by doping of the host matrix with CF 3SO 3Li at several stoichiomeric ratios with respect to EO to Li. The materials were characterized via nuclear magnetic resonance (1H NMR and 11B NMR), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry (TG) and differential scanning calorimeter (DSC). The ionic conductivity of these novel polymer electrolytes were studied by dielectric-impedance spectroscopy. Li-ion conductivity of these polymer electrolytes depends on the length of the side units as well as the doping ratio. Such electrolytes possess satisfactory ambient temperature ionic conductivity (>10 -4 S cm -1). Cyclic voltammetry results illustrated that the electrochemical stability domain extends over 4 V.

  1. Poly(vinyl alcohol)-Poly(ethylene glycol) Double-Network Hydrogel: A General Approach to Shape Memory and Self-Healing Functionalities.


    Li, Guo; Zhang, Hongji; Fortin, Daniel; Xia, Hesheng; Zhao, Yue


    A double-network polymer hydrogel composed of chemically cross-linked poly(ethylene glycol) (PEG) and physically cross-linked poly(vinyl alcohol) (PVA) was prepared. When the hydrogel (70 wt % of water) is subjected to freezing/thawing treatment under strain, the enhanced physical network as a result of crystallization of PVA chains can stabilize the hydrogel deformation after removal of the external force at room temperature. Subsequent disruption of the physical network of PVA by heating allows for the recovery of the initial shape of the hydrogel. Moreover, the double-network hydrogel exhibits self-healing capability stemming from the physical network of PVA by virtue of the extensive interchain hydrogen bonding between the hydroxyl side groups. This study thus demonstrates a general approach to imparting both the shape memory and self-healing properties to chemically cross-linked hydrogels that otherwise do not have such functionalities. Moreover, by making use of the fixed hydrogel elongation, the effect of anisotropy arising from chain orientation on the self-healing was also observed. PMID:26442631

  2. Synergistic and competitive aspects of the adsorption of poly(ethylene glycol) and poly(vinyl alcohol) onto Na-bentonite.


    Clegg, Francis; Breen, Chris; Khairuddin


    The competitive adsorption of poly(ethylene glycol) (PEG) and poly(vinyl alcohol) (PVOH) onto Na-bentonite has been assessed quantitatively. Particular emphasis was focused on the amount of organic located within the bentonite interlayer and any subsequent effects on the extent of layer expansion. The individual isotherms showed strong adsorption for both PVOH and PEG at amounts lower than the quantities required to produce a fully loaded bilayer (0.33 g of PVOH/g of clay) and single layered structures (0.10 g of PEG/g of clay), respectively. Above these concentrations, the incremental amounts adsorbed were smaller, and the concentration of adsorbates in solution gradually increased. Na-bentonite adsorbed more PVOH than PEG at any given concentration. In the competitive study, the amount of PVOH adsorbed was enhanced in the presence of PEG (0.10 and 0.30 g/g of clay), but less PEG was adsorbed. At low loadings of PVOH (0.02-0.10 g/g of clay), the amount of adsorbed PEG was increased but at higher PVOH levels PEG adsorption was reduced. The XRD data showed stepped changes in the d-spacing as the adsorbed amounts of both PEG and PVOH increased. The PEG-bentonite samples did not expand beyond a bilayer structure (18 Å), but the XRD data for PVOH-treated samples indicated the formation of multilayer structures (d ≥ 44 Å). PMID:25348503

  3. A rapid analysis of plasma/serum ethylene and propylene glycol by headspace gas chromatography.


    Ehlers, Alexandra; Morris, Cory; Krasowski, Matthew D


    A rapid headspace-gas chromatography (HS-GC) method was developed for the analysis of ethylene glycol and propylene glycol in plasma and serum specimens using 1,3-propanediol as the internal standard. The method employed a single-step derivitization using phenylboronic acid, was linear to 200 mg/dL and had a lower limit of quantitation of 1 mg/dL suitable for clinical analyses. The analytical method described allows for laboratories with HS-GC instrumentation to analyze ethanol, methanol, isopropanol, ethylene glycol, and propylene glycol on a single instrument with rapid switch-over from alcohols to glycols analysis. In addition to the novel HS-GC method, a retrospective analysis of patient specimens containing ethylene glycol and propylene glycol was also described. A total of 36 patients ingested ethylene glycol, including 3 patients who presented with two separate admissions for ethylene glycol toxicity. Laboratory studies on presentation to hospital for these patients showed both osmolal and anion gap in 13 patients, osmolal but not anion gap in 13 patients, anion but not osmolal gap in 8 patients, and 1 patient with neither an osmolal nor anion gap. Acidosis on arterial blood gas was present in 13 cases. Only one fatality was seen; this was a patient with initial serum ethylene glycol concentration of 1282 mg/dL who died on third day of hospitalization. Propylene glycol was common in patients being managed for toxic ingestions, and was often attributed to iatrogenic administration of propylene glycol-containing medications such as activated charcoal and intravenous lorazepam. In six patients, propylene glycol contributed to an abnormally high osmolal gap. The common presence of propylene glycol in hospitalized patients emphasizes the importance of being able to identify both ethylene glycol and propylene glycol by chromatographic methods. PMID:23741644

  4. [Interference of ethylene glycol on lactate assays].


    Graïne, H; Toumi, K; Roullier, V; Capeau, J; Lefèvre, G


    Ethylene glycol is broken down to three main organic acids: glycolic acid, glyoxylic acid and oxalic acid which cause severe metabolic acidosis. Effect of these three acids on lactate assays was evaluated in five blood gas analysers and two clinical chemistry analysers. For all systems, no influence of oxalic acid on lactate results could be demonstrated. No interference of glycolic acid could be observed on lactate assay performed with Rapid Lab 1265 (R: 104,9 +/- 12,1%), Vitros 950 (R: 105,7 +/- 5,3 %) and Architect ci8200 (R: 104,9 +/- 4,7%), but on the contrary, CCX 4, OMNI S, ABL 725 and 825 demonstrated a concentration-dependent interference. No interference of glyoxylic acid could be observed with Vitros 950, but a positive interference could be observed with ABL 725 and 825, OMNI S, CCX4 and Architect ci8200 A linear relationship between apparent lactate concentration found with ABL 725 and 825, OMNI S, CCX 4, and glyoxylic acid could be observed (0,94 < r < 0,99), a weaker interference being observed with Rapid Lab 1265 and Architect ci 8200. Our results demonstrated that in case of ethylene glycol poisoning, cautious interpretation of lactate assay should be done, since wrong results of lactacidemia could lead to misdiagnostic and delay patient treatment. PMID:17627925

  5. Ethylene glycol: properties, synthesis, and applications.


    Yue, Hairong; Zhao, Yujun; Ma, Xinbin; Gong, Jinlong


    Ethylene glycol (EG) is an important organic compound and chemical intermediate used in a large number of industrial processes (e.g. energy, plastics, automobiles, and chemicals). Indeed, owing to its unique properties and versatile commercial applications, a variety of chemical systems (e.g., catalytic and non-catalytic) have been explored for the synthesis of EG, particularly via reaction processes derived from fossil fuels (e.g., petroleum, natural gas, and coal) and biomass-based resources. This critical review describes a broad spectrum of properties of EG and significant advances in the prevalent synthesis and applications of EG, with emphases on the catalytic reactivity and reaction mechanisms of the main synthetic methodologies and applied strategies. We also provide an overview regarding the challenges and opportunities for future research associated with EG. PMID:22488259

  6. Degradation of ethylene glycol using Fenton's reagent and UV.


    McGinnis, B D; Adams, V D; Middlebrooks, E J


    Oxidation of ethylene glycol in aqueous solutions was found to occur with the addition of Fenton's reagent with further conversion observed upon UV irradiation. The pH range studied was 2.5-9.0 with initial H2O2 concentrations ranging from 100 to 1000 mg/l. Application of this method to airport storm-water could potentially result in reduction of chemical oxygen demand by conversion of ethylene glycol to oxalic and formic acids. Although the amount of H2O2 added follows the amount of ethylene glycol degraded, smaller H2O2 doses were associated with increases in the ratio of ethylene glycol removed per unit H2O2 added indicating the potential of pulsed doses or constant H2O2 feed systems. Ethylene glycol removal was enhanced by exposure to UV light after treatment with Fenton's reagent, with rates dependent on initial H2O2 concentration. In addition to ethylene glycol, the principle products of this reaction, oxalic and formic acids, have been shown to be mineralized in other HO generating systems presenting the potential for ethylene glycol mineralization in this system with increased HO* production. PMID:11572583

  7. Heat-transfer tests of aqueous ethylene glycol solutions in an electrically heated tube

    NASA Technical Reports Server (NTRS)

    Bernardo, Everett; Eian, Carroll S


    As part of an investigation of the cooling characteristics of liquid-cooled engines, tests were conducted with an electrically heated single-tube heat exchanger to determine the heat-transfer characteristics of an-e-2 ethylene glycol and other ethylene glycol-water mixtures. Similar tests were conducted with water and commercial butanol (n-butyl alcohol) for check purposes. The results of tests conducted at an approximately constant liquid-flow rate of 0.67 pound per second (Reynolds number, 14,500 to 112,500) indicate that at an average liquid temperature 200 degrees f, the heat-transfer coefficients obtained using water, nominal (by volume) 30 percent-70 percent and 70 percent-30 percent glycol-water mixtures are approximately 3.8, 2.8, and 1.4 times higher, respectively, than the heat-transfer coefficients obtained using an-e-2 ethylene glycol.

  8. Redox-labelled poly(ethylene glycol) used as a diffusion probe in poly(ethylene glycol) melts

    SciTech Connect

    Haas, O.; Velasquez, C.; Porat, Z.


    Ferrocene labelled monomethyl poly(ethylene glycol) MPEG with molecular weights of 1900 and 750 was prepared and used as an electrochemical diffusion probe in poly(ethylene glycol) melts. Cyclic voltammetry and chronoamperometry were used in connection with microdisk electrodes to measure the diffusion coefficient of redox tagged molecules using melted poly(ethylene glycol) as a solvent. The molecular weight of the solvent polymer was 750, 2000 and 20000. Results from the temperature dependency of the diffusion process and of the viscosity and conductivity of the polymer electrolyte are presented and discussed.

  9. Analysis of automobile radiator performance with ethylene glycol/water and propylene glycol/water coolants

    SciTech Connect

    Gollin, M.; Bjork, D.


    The heat transfer and hydraulic performance of the following coolants was examined in five automobile radiators in a wind tunnel: 100% water; 100% propylene glycol; 70/30 propylene glycol/water (volume); 50/50 propylene glycol/water (volume); 70/30 ethylene glycol/water (volume); 50/50 ethylene glycol water (volume). The results of these studies are presented to demonstrate the relative performance of these coolant mixtures in terms of heat transfer, coolant pressure drop and radiator effectiveness for a range of coolant and air flowrates. It is concluded that the most effective of the coolants in transferring heat in the test radiators was water, followed by 50/50 ethylene glycol/water, 50/50 propylene glycol/water, 70/30 ethylene glycol/water, 70/30 propylene glycol and, finally, 100% propylene glycol. There will be a negligible differences between the performance of a radiator using a 50/50 propylene glycol/water coolant and a 50/50 ethylene glycol/water coolant. It is estimated that, with 50/50 propylene glycol coolant replacing 50/50 ethylene glycol/water, the temperature of the coolant throughout the cooling loop will increase by approximately 5%. The effect that the flow regime (fully turbulent/transition/laminar) has upon the performance of a given radiator/coolant combination was found to be significant. The design of the coolant passages in radiators can affect the onset of fully turbulent flow in the coolant passages in a radiator.

  10. Intercalation of ethylene glycol into yttrium hydroxide layered materials.


    Xi, Yuanzhou; Davis, Robert J


    Intercalation of ethylene glycol into layered yttrium hydroxide containing nitrate counterions was accomplished by heating the reagents in a methanol solution of sodium methoxide under autogenous pressure at 413 K for 20 h. The resulting crystalline material had an expanded interlayer distance of 10.96 A, confirming the intercalation of an ethylene glycol derived species. Characterization of the material by FT-IR spectroscopy, thermogravimetric analysis, and the catalytic transesterification of tributyrin with methanol was consistent with direct bonding of ethylene glycolate anions (O(2)C(2)H(5)(-)) to the yttrium hydroxide layers, forming Y-O-C bonds. The layers of the material are proposed to be held together by H-bonding between the hydroxyls of grafted ethylene glycol molecules attached to adjacent layers. Glycerol can also be intercalated into yttrium hydroxide layered materials by a similar method. PMID:20302308

  11. Human inhalation exposure to ethylene glycol.


    Carstens, Jörn; Csanády, György A; Faller, Thomas H; Filser, Johannes G


    Two male volunteers (A and B) inhaled 1.43 and 1.34 mmol, respectively, of vaporous (13)C-labeled ethylene glycol ((13)C(2)-EG) over 4 h. In plasma, (13)C(2)-EG and its metabolite (13)C(2)-glycolic acid ((13)C(2)-GA) were determined together with the natural burden from background GA using a gas chromatograph equipped with a mass selective detector. Maximum plasma concentrations of (13)C(2)-EG were 11.0 and 15.8 micromol/l, and of (13)C(2)-GA were 0.9 and 1.8 micromol/l, for volunteers A and B, respectively. Corresponding plasma half-lives were 2.1 and 2.6 h for (13)C(2)-EG, and 2.9 and 2.6 h for (13)C(2)-GA. Background GA concentrations were 25.8 and 28.3 micro mol/l plasma. Unlabeled background EG, GA and oxalic acid (OA) were detected in urine in which the corresponding (13)C-labeled compounds were also quantified. Within 28 h after the start of the exposures, 6.4% and 9.3% (13)C(2)-EG, 0.70% and 0.92% (13)C(2)-GA, as well as 0.08% and 0.28% (13)C(2)-OA of the inhaled amounts of (13)C(2)-EG, were excreted in urine by volunteers A and B, respectively. The amounts of (13)C(2)-GA represented 3.7% and 14.2% of background urinary GA excreted over 24 h (274 and 88 micromol). The amounts of (13)C(2)-OA were 0.5% and 2.1% of background urinary OA excreted over 24 h (215 and 177 micromol). From the findings obtained in plasma and urine and from a toxicokinetic analysis of these data, it is highly unlikely that workplace EG exposure according to the German exposure limit (MAK-value 10 ppm EG, 8 h) could lead to adverse effects from the metabolically formed GA and OA. PMID:12856104

  12. Safe antifreeze: The real difference between ethylene glycol and propylene glycol

    SciTech Connect

    Wray, T.K.


    Antifreeze-coolants are added to the radiators of internal combustion engines to prevent freezing during the winter and boil-over during the summer. Although ethylene glycol is the most commonly used coolant, products containing propylene glycol have been used--at least, experimentally--for years. Both substances have similar characteristics; however, some manufacturers claim that antifreeze-coolants containing propylene glycol are more environmentally friendly and safer to humans and animals than ethylene glycol products. This article examines these two substances, and addresses the similarities and differences of their physical and chemical compounds, thereby enabling users to determine whether such claims are valid or merely advertising hyperbole.

  13. Molecularly uniform poly(ethylene glycol) certified reference material

    NASA Astrophysics Data System (ADS)

    Takahashi, Kayori; Matsuyama, Shigetomo; Kinugasa, Shinichi; Ehara, Kensei; Sakurai, Hiromu; Horikawa, Yoshiteru; Kitazawa, Hideaki; Bounoshita, Masao


    A certified reference material (CRM) for poly(ethylene glycol) with no distribution in the degree of polymerization was developed. The degree of polymerization of the CRM was accurately determined to be 23. Supercritical fluid chromatography (SFC) was used to separate the molecularly uniform polymer from a standard commercial sample with wide polydispersity in its degree of polymerization. Through the use of a specific fractionation system coupled with SFC, we are able to obtain samples of poly(ethylene glycol) oligomer with exact degrees of polymerization, as required for a CRM produced by the National Metrology Institute of Japan.

  14. Insight into the formation of magnetite mesocrystals from ferrous precursors in ethylene glycol.


    Wan, Jiaqi; Tang, Jing; Zhang, Chongyu; Yuan, Ruiting; Chen, Kezheng


    Uniform magnetite mesocrystals were fabricated by solvothermal treatment of ferrous chloride in ethylene glycol in the presence of sodium hydroxide. The formation mechanism of magnetite mesocrystals in ethylene glycol was deduced by a time-dependent experiment. PMID:26255597

  15. Comparative acute and subchronic toxicity of ethylene glycol monopropyl ether and ethylene glycol monopropyl ether acetate.

    PubMed Central

    Katz, G V; Krasavage, W J; Terhaar, C J


    The acute toxicity of ethylene glycol monopropyl ether (EGPE) and ethylene glycol monopropyl ether acetate (EGPEA) was determined in a series of standardized tests. The oral LD50 in rats was 3089 and 9456 mg/kg EGPE and EGPEA, respectively. Skin irritation was slight following an occluded single dose application of either compound to the guinea pig abdomen. The dermal LD50 for guinea pigs was 1 to 5 mL/kg and greater than 20 mL/kg EGPE and EGPEA, respectively. EGPE produced a very weak positive sensitization response in one of five guinea pigs. No positive response was elicited when 10 guinea pigs were similarly challenged with EGPEA. EGPE produced transient moderate to severe eye irritation in rabbits while EGPEA produced slight eye irritation. Subchronic toxicity was determined in a series of oral and inhalation studies. Groups of 10 male rats were dosed with 15, 7.5, 3.75 or 1.88 mmole/kg EGPE and 30, 15 or 7.5 mmole/kg EGPEA by gavage 5 days/week for 6 weeks. Hemoglobinuria was seen at least once at all dose levels of both compounds. EGPE had little effect on feed consumption or body weight gain, while body weight gain was reduced in the two high dose groups exposed to EGPEA and feed consumption was reduced at all dose levels. Hematologic changes were seen at all dose levels of both compounds. Absolute and/or relative spleen weights were increased at all but the lowest EGPE dose level and at all EGPEA dose levels. Gross and histopathologic examinations revealed significant effects on the spleen of animals exposed to EGPE and on the spleen, liver, kidney and testes of animals exposed to EGPEA. The no-observed effect level (NOEL) for splenic changes was 1.88 mmole/kg EGPE. A NOEL for hematology was not established. The NOEL for liver and testicular changes were 15 and 7.5 mmole/kg EGPEA, respectively while a NOEL for hematologic, splenic and renal changes was not established. Groups of 10 rats (5M, 5F) were exposed to 800, 400, 200 or 100 ppm EGPE or EGPEA 6 hr

  16. Detection of ethylene glycol - toward W51/e2 and G34.3+0.02

    NASA Astrophysics Data System (ADS)

    Lykke, Julie M.; Favre, Cécile


    Ethylene glycol (HOCH2CH2OH), also commenly known as antifreeze, is the reduced alcohol version of glycolaldehyde (CH2OHCHO). Glycoladehyde - the simplest possible aldehyde sugar (Marstokk and Møllendal 1973) - is the first intermediate step in the path toward forming more complex and biologically relevant molecules through the the formose reaction, which begins with formaldehyde (H2CO) and ends with the formation of sugars and ultimately ribose, the backbone of RNA (e.g., Larralde et al. 1995). The presence of glycolaldehyde is therefore an important indication that processes leading to biologically relevant molecules are taking place. It is however, still unclear as to how glycolaldehyde and ethylene glycol are formed in the ISM. It has been proposed that they share a common formation pathway through UV-irradiation of methanol (CH3OH) ices mixed with CO (Öberg et al. 2009). So far, ethylene glycol, in its lower energy con-former (g’Ga(CH2OH)2), has been detected toward SgrB2 (N) by Hollis et al. (2002), tentatively toward IRAS 16293-2422 (Jørgensen et al. 2012) and marginally by Kalenskii and Johansson (2010) toward W51 e1/e2. Here we present a firm detection of ethylene glycol toward W51/e2 as well as a first detection toward G34.3+0.02 at 1mm and 3mm using the IRAM 30m telescope.

  17. Direct Routes from Synthesis Gas to Ethylene Glycol.

    ERIC Educational Resources Information Center

    Dombek, B. D.


    Discusses the synthesis of ethylene glycol from carbon monoxide and hydrogen using bimetallic catalysts. Although this technology has not been implemented, it illustrates two important future trends, namely, use of bimetallic catalysts and use of coal-derived carbon monoxide and hydrogen as a new feed stock. (JN)

  18. Ethylene glycol toxicosis in adult beef cattle fed contaminated feeds

    PubMed Central

    Barigye, Robert; Mostrom, Michelle; Dyer, Neil W.; Newell, Teresa K.; Lardy, Gregory P.


    Acute deaths of cows held in a drylot and fed several crop processing plant by-products were investigated. Clinical signs in affected cows included diarrhea, ataxia, recumbency, hypersalivation, and sunken eyes. A histological diagnosis of ethylene glycol toxicosis, based on numerous birefringent crystals in renal tubules, was supported by toxicologic findings. PMID:19119372

  19. Electrochemical measurements of diffusion coefficients of redox-labeled poly(ethylene glycol) dissolved in poly(ethylene glycol) melts

    SciTech Connect

    Haas, O.; Velazquez, C.S.; Porat, Z.; Murray, R.W.


    Ferrocene labeled monomethoxy-poly(ethylene glycol)s (MPEG) with molecular weights of 1900 and 750 were used as redox probe solutes in poly(ethylene glycol) melt solvents of molecular weight 750, 2000, and 20000. Cyclic voltammetry and chronoamperometry at microdisk electrodes were employed to measure the diffusion coefficients of the redox probes, which were independent of the probe concentration and varied between 10{sup -7} and 10{sup -10} cm{sup 2}/s. Diffusional activation barrier results also suggest that the ferrocene label does not significantly influence the diffusivity of the probe molecule in the host solvent. Activation barrier, viscosity, and ionic conductivity results show that the LiClO{sub 4} electrolyte does not influence the diffusion barrier or viscosity as long as the ether O/Li{sup +} ratio is >=250 (ca. 0.1 M) which is still a sufficient electrolyte concentration to allow quantitative electrochemical diffusion measurements. 21 refs., 7 figs., 2 tabs.

  20. Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles

    SciTech Connect

    Eastman, J. A.; Choi, S. U. S.; Li, S.; Yu, W.; Thompson, L. J.


    It is shown that a ''nanofluid'' consisting of copper nanometer-sized particles dispersed in ethylene glycol has a much higher effective thermal conductivity than either pure ethylene glycol or ethylene glycol containing the same volume fraction of dispersed oxide nanoparticles. The effective thermal conductivity of ethylene glycol is shown to be increased by up to 40% for a nanofluid consisting of ethylene glycol containing approximately 0.3 vol% Cu nanoparticles of mean diameter <10 nm. The results are anomalous based on previous theoretical calculations that had predicted a strong effect of particle shape on effective nanofluid thermal conductivity, but no effect of either particle size or particle thermal conductivity.

  1. Science and the perceived environmental risk from ethylene glycol and propylene glycol

    SciTech Connect

    Snellings, W.M.; Shah, S.I.; Garska, D.; Williams, J.B.


    Ethylene glycol and propylene glycol are widely used in aircraft deicing fluids (ADF), heat transfer fluids, and engine coolants. Discharges of these compounds to the environment have been reduced in recent years, but remain significant. The perceived environmental risk affects the decisions of businesses and regulatory agencies. There is a perception that propylene glycol poses a lower environmental risk than ethylene glycol. This perception is an inference from the use of low concentrations of propylene glycol in food additives -- something safe for food must be safe for fish. Environmental risk, however, must be established on the basis of scientific data, including acute and chronic toxicity to freshwater and saltwater species, oxygen demand, and persistence. A review of aquatic toxicity data for marine and freshwater species, and a review of treatability data in wastewater and soil for these widely used compounds has been completed. The data show that the two compounds, in fact, pose similar environmental risks, and in certain aspects one or the other glycol appears to be preferable. All aspects must be considered to give a valid perception of risk. The role of additives in deicing fluids is significant. Environmental fate and effect data indicate that additives are usually more toxic than the glycols, and environmental data for particular formulations must be evaluated as part of any risk assessment.

  2. Vapor Pressure of Aqueous Solutions of Ethylene Glycol

    NASA Astrophysics Data System (ADS)

    Fujita, Toshihiko; Kikuchi, Sakae

    Vapor pressures of aqueous solutions of ethylene glycol are measured in the range of temperature from -10 to 60°C and concentration from 20 to 50wt%. In a low concentration range, the measured values of vapor pressure decrease according to the Raoult's law independent of temperature, while in a high concentration range, they show a trend to decrease towards the estimated values of freezing point with decreasing temperature. The following correlation equation is obtained for practical calculations on heating towers and the like. log(p/P0) = 5.351 - 6.4×10-4y + (1817 + 0.008y(y + 10))/(t + 240) where p, vapor perssure of aqueous solutions of ethylene glycol [kPa] ; P0, atmospheric pressure [=101.325kPa] ; y, concentration [wt%] ; t, temperature [°C].

  3. Effects of low temperature on the biodegradation of ethylene glycol and propylene glycol

    SciTech Connect

    Williams, J.B.; Blessing, R.L.


    Ethylene glycol and propylene glycol are used in a variety of applications. These compounds are well known to biodegrade readily at 20 C, which is the benchmark temperature for most biodegradation studies. These compounds may enter the environment when the ambient temperatures are significantly below 20 C. Biodegradation data at low temperatures was needed. For example, wintertime airport stormwater discharges contain glycols from deicing fluids. These compounds may enter streams at ambient winter temperatures, or wastewater treatment works which may be operating at temperatures well below 20 C. Biodegradation studies were conducted with BOD bottles incubated at 40 C and 10 C. Biodegradation was slower than 20 C but still significant. For ethylene glycol, the half-life (time at which one-half of the oxygen demand was consumed by the microorganisms) was 5 days at 20 C, 8 days at 10 C, and 25 days at 40 C. For propylene glycol, the half-life was 5 days at 20 C, 12 days at 10 C, and 28 days at 40 C. Two aircraft deicing fluids were also tested, and similar degradation rates were observed. This indicates the presence of additives in deicing fluids has little effect on biodegradation of glycols.

  4. [Three-fold ethylene glycol poisoning over 3 years--a case report].


    Gardias, Waldemar; Szponar, Jarosław; Kujawa, Anna; Majewska, Magdalena; Drelich, Grzegorz; Lewandowska-Stanek, Hanna


    This paper describes a case of now 49-year-old patient with alcohol dependence syndrome, hospitalized three times in the Center of Clinical Toxicology in 2009-2012 due to ethylene glycol poisoning. Twice, the course of poisoning was defined as severe. It was complicated by respiratory failure, severe metabolic acidosis, renal failure, disorders of the central nervous system; once referred to it as a medium, complicated by renal failure. He was treated with ethyl alcohol as an inhibitor of alcohol dehydrogenase, hemodialysess and intensive symptomatic and supportive therapy. This paper shows the great effectiveness of early hemodialysis and intensive therapy even in case of multiple and severe intoxication with toxic alcohols. PMID:23243938

  5. Acute and subchronic toxicity of ethylene glycol monobutyl ether.

    PubMed Central

    Tyler, T R


    The available information on the acute and subchronic toxicity of ethylene glycol monobutyl ether is reviewed. Data from animal studies have been examined from the standpoint of dose-response relationships and the sensitivity of various animal species, including man, to the effects of this chemical. In view of recent findings with other chemically related glycol ethers, particular attention has been given to possible adverse effects on blood and testicular tissue. In evaluating the hazard that this chemical may pose to man, consideration has been given to likely routes of exposure and its irritant properties. It is concluded that the available information continues to support the current ACGIH TWA8-TLV of 25 ppm with a STEL of 75 ppm. PMID:6499803

  6. Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid

    NASA Astrophysics Data System (ADS)

    Yadav, Vishnu P.; Mukherjee, Rudra Palash; Bantraj, Kandi; Maity, Sunil K.


    The reaction kinetics of the esterification of ethylene glycol with acetic acid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

  7. Brillouin and Raman Scattering Study of Ethylene Glycol Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Seshimo, Y.; Ike, Y.; Kojima, S.


    We studied the cluster structure of ethylene glycol aqueous solutions by Brillouin and Raman scattering. We measured the ultrasonic sound velocity of the sample by Brillouin scattering. From the concentration dependence of the sound velocity, we studied the cluster structure in the solution. We showed that the number of H2O molecule neighboring a EG molecule becomes a little higher with increasing temperature and the intermolecular interaction between EG and H2O molecules weakened with increasing temperature. In Raman scattering study, We studied the hydrogen bond in the solution using the OD stretching band. We revealed that the strength of the hydrogen bond is independent of the EG concentration.

  8. Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid

    SciTech Connect

    Yadav, Vishnu P.; Maity, Sunil K.; Mukherjee, Rudra Palash; Bantraj, Kandi


    The reaction kinetics of the esterification of ethylene glycol with acetic acid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

  9. Thermal stability of collagen fibers in ethylene glycol.


    Miles, C A; Burjanadze, T V


    The mechanism that renders collagen molecules more stable when precipitated as fibers than the same molecules in solution is controversial. According to the polymer-melting mechanism the presence of a solvent depresses the melting point of the polymer due to a thermodynamic mechanism resembling the depression of the freezing point of a solvent due to the presence of a solute. On the other hand, according to the polymer-in-a-box mechanism, the change in configurational entropy of the collagen molecule on denaturation is reduced by its confinement by surrounding molecules in the fiber. Both mechanisms predict an approximately linear increase in the reciprocal of the denaturation temperature with the volume fraction (epsilon) of solvent, but the polymer-melting mechanism predicts that the slope is inversely proportional to the molecular mass of the solvent (M), whereas the polymer-in-a-box mechanism predicts a slope that is independent of M. Differential scanning calorimetry was used to measure the denaturation temperature of collagen in different concentrations of ethylene glycol (M = 62) and the slope found to be (7.29 +/- 0.37) x 10(-4) K(-1), compared with (7.31 +/- 0.42) x 10(-4) K(-1) for water (M = 18). This behavior was consistent with the polymer-in-a-box mechanism but conflicts with the polymer-melting mechanism. Calorimetry showed that the enthalpy of denaturation of collagen fibers in ethylene glycol was high, varied only slowly within the glycol volume fraction range 0.2 to 1, and fell rapidly at low epsilon. That this was caused by the disruption of a network of hydrogen-bonded glycol molecules surrounding the collagen is the most likely explanation. PMID:11222308

  10. Behavioral teratology of ethylene glycol monomethyl and monoethyl ethers

    SciTech Connect

    Nelson, B.K.; Brightwell, W.S.


    A recent addition to the field of teratology has been the inclusion of functional assessment techniques of offspring after prenatal exposure to exogenous agents. The present paper reviews the behavioral teratogenic effects of ethylene glycol monomethyl ether (EGME, 2-methoxyethanol) and ethylene glycol monoethyl ether (EGEE, 2-ethoxyethanol). Groups of 15 pregnant rats were exposed via inhalation to 25 ppm EGME or to 100 ppm EGEE on gestation days 7 to 13 or 14 to 20. An equal number of sham-exposed controls were included for both periods of gestation. The only effect noted in the maternal animals was a slightly prolonged gestation in the group exposed to 100 ppm EGEE on days 14 to 20. Litters were culled in four female and four male pups on the day of birth. Pups of each sex from all litters were tested on a variety of behavioral tasks (including tests of neuromuscular ability, activity, and learning ability) extending from postnatal days 10 to 90. In addition, brains from newborn and from 21-day-old offspring were removed and analyzed for concentrations of the neurotransmitters acetylcholine, dopamine, norepinephrine, and 5-hydroxytryptamine (serotonin). Both the behavioral testing and the neurochemical evaluations revealed functional alterations in the litter groups experiencing prenatal exposure to EGME and EGEE at concentrations which produced no observable effects in the maternal animals. 6 references, 3 tables.

  11. Hydrogenolysis of ethylene glycol to methanol over modified RANEY® catalysts.


    Wu, Cheng-Tar; Qu, Jin; Elliott, Joseph; Yu, Kai Man Kerry; Tsang, Shik Chi Edman


    There is tremendous growing interest in utilizing biomass molecules for energy provision due to their carbon neutrality. Here, we employ ethylene glycol as a model compound for catalytic activation, which represents a basic unit for complex carbohydrate molecules (polyols). In this paper, hydrogenolysis of ethylene glycol to produce methanol in hydrogen over modified RANEY® Ni and Cu catalysts has been studied. This work provides essential information that may leads to the development of new catalysts for carbohydrate activation to methanol, a novel but important reaction concerning biomass conversion to transportable form of energy. Particularly, in this study, modification of electronic structure hence adsorption properties of RANEY® catalysts has mainly been achieved by blending with second metal(s). It is found that the activity and selectivity of this reaction can be significantly affected by this approach. In contrast, there is no subtle effect on methanol selectivity despite a great variation in the d-band centre position which shows a distinctive effect on other products. This result suggests that methanol is produced on specific surface sites independent from the other sites at an intrinsic rate and will not be converted to other products by the d-band alteration. PMID:23661262

  12. Thermophysical properties of ethylene glycol mixture based CNT nanofluids

    NASA Astrophysics Data System (ADS)

    Camarano, D. M.; Mansur, F. A.; Araújo, T. L. C. F.; Salles, G. C.; Santos, A. P.


    Nanofluids are produced by dispersing nanometer-scale solid particles into base liquids such as water, ethylene glycol, etc. The thermal quadrupole method is utilized to determine the thermophysical properties of materials. By this technique, the thermal diffusivity and conductivity of different nanofluids containing the surfactants humic acid, sodium salt of humic acid and sodium carboxymethyl cellulose and multi-wall carbon nanotubes were evaluated at room temperature and at 75 oC. Values of thermal diffusivity varying in the range from 9.60x10-8 m2s-1 to 1.46x10-7 m2s-1 and thermal conductivity from 0.26 Wm-1K-1 to 41 Wm-1K-1 were obtained. As main conclusions, it was noted that nanofluids exhibit superior heat transfer characteristics than the conventional heat transfer fluid and the thermal conductivity is enhanced by 50% for the nanofluid containing 0.0275 mg/mL of sodium salt of humic acid + ethylene glycol, at the temperature of 25 oC.

  13. Ru-Containing Magnetically Recoverable Catalysts: A Sustainable Pathway from Cellulose to Ethylene and Propylene Glycols.


    Manaenkov, Oleg V; Mann, Joshua J; Kislitza, Olga V; Losovyj, Yaroslav; Stein, Barry D; Morgan, David Gene; Pink, Maren; Lependina, Olga L; Shifrina, Zinaida B; Matveeva, Valentina G; Sulman, Esther M; Bronstein, Lyudmila M


    Biomass processing to value-added chemicals and biofuels received considerable attention due to the renewable nature of the precursors. Here, we report the development of Ru-containing magnetically recoverable catalysts for cellulose hydrogenolysis to low alcohols, ethylene glycol (EG) and propylene glycol (PG). The catalysts are synthesized by incorporation of magnetite nanoparticles (NPs) in mesoporous silica pores followed by formation of 2 nm Ru NPs. The latter are obtained by thermal decomposition of ruthenium acetylacetonate in the pores. The catalysts showed excellent activities and selectivities at 100% cellulose conversion, exceeding those for the commercial Ru/C. High selectivities as well as activities are attributed to the influence of Fe3O4 on the Ru(0)/Ru(4+) NPs. A facile synthetic protocol, easy magnetic separation, and stability of the catalyst performance after magnetic recovery make these catalysts promising for industrial applications. PMID:27484222

  14. Effects of sterilization on poly(ethylene glycol) hydrogels.


    Kanjickal, Deenu; Lopina, Stephanie; Evancho-Chapman, M Michelle; Schmidt, Steven; Donovan, Duane


    The past few decades have witnessed a dramatic increase in the development of polymeric biomaterials. These biomaterials have to undergo a sterilization procedure before implantation. However, many sterilization procedures have been shown to profoundly affect polymer properties. Poly(ethylene glycol) hydrogels have gained increasing importance in the controlled delivery of therapeutics and in tissue engineering. We evaluated the effect of ethylene oxide (EtO), hydrogen peroxide (H(2)O(2)), and gamma sterilization of poly(ethylene glycol) hydrogels on properties relevant to controlled drug delivery and tissue engineering. We observed that the release of cyclosporine (CyA) (an immunosuppressive drug that is effective in combating tissue rejection following organ transplantation) was significantly affected by the type of sterilization. However, that was not the case with rhodamine B, a dye. Hence, the drug release characteristics were observed to be dependent not only on the sterilization procedure but also on the type of agent that needs to be delivered. In addition, differences in the swelling ratios for the sterilized and unsterilized hydrogels were statistically significant for 1:1 crosslinked hydrogels derived from the 8000 MW polymer. Significant differences were also observed for gamma sterilization for 1:1 crosslinked hydrogels derived from the 3350 MW polymer and also the 2:1 crosslinked hydrogels derived from the 8000 MW polymer. Atomic force microscopy (AFM) studies revealed that the roughness parameter for the unsterilized and EtO-sterilized PEG hydrogels remained similar. However, a statistically significant reduction of the roughness parameter was observed for the H(2)O(2) and gamma-sterilized samples. Electron spin resonance (ESR) studies on the unsterilized and the sterilized samples revealed the presence of the peroxy and the triphenyl methyl carbon radical in the samples. The gamma and the H(2)O(2)-sterilized samples were observed to have a much

  15. A thermosensitive hydrogel based on biodegradable amphiphilic poly(ethylene glycol) polycaprolactone poly(ethylene glycol) block copolymers

    NASA Astrophysics Data System (ADS)

    Gong, Chang Yang; Qian, Zhi Yong; Liu, Cai Bing; Juan Huang, Mei; Gu, Ying Chun; Wen, Yan Jun; Kan, Bing; Wang, Ke; Dai, Mei; Li, Xing Yi; Gou, Ma Ling; Tu, Ming Jing; Wei, Yu Quan


    A series of low molecular weight poly(ethylene glycol)-polycaprolactone-poly(ethylene glycol) (PEG-PCL-PEG) biodegradable block copolymers were successfully synthesized using isophorone diisocyanate (IPDI) as the coupling agent, and were characterized using 1H NMR and Fourier transform infrared spectroscopy. The aqueous solutions of the PEG-PCL-PEG copolymers displayed a special thermosensitive gel-sol transition when the concentration was above the corresponding critical gel concentration. Gel-sol phase diagrams were recorded using the test-tube-inversion method; they depended on the hydrophilic/hydrophobic balance in the macromolecular structure, as well as some other factors, including the heating history, volume, and the ageing time of the copolymer aqueous solutions and dissolution temperature of the copolymers. As a result, the gel-sol transition temperature range could be altered, which might be very useful for application in injectable drug delivery systems. This work was financially supported by the Chinese Key Basic Research Program (2004CB518800 and 2004CB518807), and the Sichuan Key Project of Science and Technology (06(05SG022-021-02)).


    EPA Science Inventory

    In order to determine the merit of a petition to remove ethylene glycol ether (EGBE) from the Agency's Hazardous Air Pollutant (HAP) list, EPA has developed an interim final position paper, An Evaluation of the Human Carcinogenic Potential of Ethylene Glycol Butyl Ether, t...

  17. On the origin of reactivity of steam reforming of ethylene glycol on supported Ni catalysts.


    Li, Shuirong; Zhang, Chengxi; Zhang, Peng; Wu, Gaowei; Ma, Xinbin; Gong, Jinlong


    This paper describes a strategy for producing hydrogen via steam reforming of ethylene glycol over supported nickel catalysts. Nickel plays a crucial role in conversion of ethylene glycol and production of hydrogen, while oxide supports affect product distribution of carbonaceous species. A plausible reaction pathway is proposed based on our results and the literature. PMID:22246195

  18. Prehospital diagnosis of massive ethylene glycol poisoning and use of an early antidote.


    Amathieu, Roland; Merouani, Medhi; Borron, Stephen W; Lapostolle, Frédéric; Smail, Nadia; Adnet, Frédéric


    We report the case of a patient suspected of voluntary massive poisoning by ethylene glycol. Prehospital diagnosis was established by portable blood analyser and an early antidote with 4 MP treatment initiated in out-of-hospital setting. Use of portable blood analyser in prehospital care should be considered in case of suspected massive poisoning by ethylene glycol. PMID:16808995

  19. Poly(ethylene glycol)-grafted copolymers as synthetic equivalents of benzyltriethylammonium chloride for triphase catalytic alkylation

    SciTech Connect

    Kimura, Y.; Kirszensztejn, P.; Regan, S.L.


    Synthetic results are reported, which show that simple poly(ethylene glycols) grafted to cross-linked polystyrene are remarkably active and stable triphase catalysts for the alkylation of nitriles, ketones, and alcohols. Resins were prepared from commercial chloromethylated polystyrene by using standard grafting procedures. For comparison of their efficacies for promoting alkylation, the conversion of phenylacetonitrile to 2-phenylhexane-nitrile was chosen as a standard reaction.

  20. Rheological profile of boron nitride–ethylene glycol nanofluids

    SciTech Connect

    Żyła, Gaweł; Witek, Adam; Gizowska, Magdalena


    The paper presents the complete rheological profile of boron nitride (BN)–ethylene glycol (EG) nanofluids. Nanofluids have been produced by two-step method on the basis of commercially available powder of plate-like grains of nanometrical thickness. Viscoelastic structure has been determined in oscillatory measurements at a constant frequency and temperature. Viscosity and flow curves for these materials have been measured. Studies have shown that the Carreau model can be used for the modeling of dynamic viscosity curves of the material. The samples were tested for the presence of thixotropy. The dependence of viscosity on temperature was also examined. The effect of temperature on the dynamic viscosity of BN-EG nanofluids can be modelled with the use of Vogel-Fulcher-Tammann expression.

  1. Fabrication of poly(ethylene glycol) hydrogel microstructures using photolithography.


    Revzin, A; Russell, R J; Yadavalli, V K; Koh, W G; Deister, C; Hile, D D; Mellott, M B; Pishko, M V


    The fabrication of hydrogel microstructures based upon poly(ethylene glycol) diacrylates, dimethacrylates, and tetraacrylates patterned photolithographically on silicon or glass substrates is described. A silicon/silicon dioxide surface was treated with 3-(trichlorosilyl)propyl methacrylate to form a self-assembled monolayer (SAM) with pendant acrylate groups. The SAM presence on the surface was verified using ellipsometry and time-of-flight secondary ion mass spectrometry. A solution containing an acrylated or methacrylated poly(ethylene glycol) derivative and a photoinitiator (2,2-dimethoxy-2-phenylacetophenone) was spin-coated onto the treated substrate, exposed to 365 nm ultraviolet light through a photomask, and developed with either toluene, water, or supercritical CO2. As a result of this process, three-dimensional, cross-linked PEG hydrogel microstructures were immobilized on the surface. Diameters of cylindrical array members were varied from 600 to 7 micrometers by the use of different photomasks, while height varied from 3 to 12 micrometers, depending on the molecular weight of the PEG macromer. In the case of 7 micrometers diameter elements, as many as 400 elements were reproducibly generated in a 1 mm2 square pattern. The resultant hydrogel patterns were hydrated for as long as 3 weeks without delamination from the substrate. In addition, micropatterning of different molecular weights of PEG was demonstrated. Arrays of hydrogel disks containing an immobilized protein conjugated to a pH sensitive fluorophore were also prepared. The pH sensitivity of the gel-immobilized dye was similar to that in an aqueous buffer, and no leaching of the dye-labeled protein from the hydrogel microstructure was observed over a 1 week period. Changes in fluorescence were also observed for immobilized fluorophore labeled acetylcholine esterase upon the addition of acetyl acholine. PMID:12448421

  2. Fabrication of poly(ethylene glycol) hydrogel microstructures using photolithography

    NASA Technical Reports Server (NTRS)

    Revzin, A.; Russell, R. J.; Yadavalli, V. K.; Koh, W. G.; Deister, C.; Hile, D. D.; Mellott, M. B.; Pishko, M. V.


    The fabrication of hydrogel microstructures based upon poly(ethylene glycol) diacrylates, dimethacrylates, and tetraacrylates patterned photolithographically on silicon or glass substrates is described. A silicon/silicon dioxide surface was treated with 3-(trichlorosilyl)propyl methacrylate to form a self-assembled monolayer (SAM) with pendant acrylate groups. The SAM presence on the surface was verified using ellipsometry and time-of-flight secondary ion mass spectrometry. A solution containing an acrylated or methacrylated poly(ethylene glycol) derivative and a photoinitiator (2,2-dimethoxy-2-phenylacetophenone) was spin-coated onto the treated substrate, exposed to 365 nm ultraviolet light through a photomask, and developed with either toluene, water, or supercritical CO2. As a result of this process, three-dimensional, cross-linked PEG hydrogel microstructures were immobilized on the surface. Diameters of cylindrical array members were varied from 600 to 7 micrometers by the use of different photomasks, while height varied from 3 to 12 micrometers, depending on the molecular weight of the PEG macromer. In the case of 7 micrometers diameter elements, as many as 400 elements were reproducibly generated in a 1 mm2 square pattern. The resultant hydrogel patterns were hydrated for as long as 3 weeks without delamination from the substrate. In addition, micropatterning of different molecular weights of PEG was demonstrated. Arrays of hydrogel disks containing an immobilized protein conjugated to a pH sensitive fluorophore were also prepared. The pH sensitivity of the gel-immobilized dye was similar to that in an aqueous buffer, and no leaching of the dye-labeled protein from the hydrogel microstructure was observed over a 1 week period. Changes in fluorescence were also observed for immobilized fluorophore labeled acetylcholine esterase upon the addition of acetyl acholine.

  3. Fluorescence spectroscopy of individual semiconductor nanoparticles in different ethylene glycols.


    Flessau, Sandra; Wolter, Christopher; Pöselt, Elmar; Kröger, Elvira; Mews, Alf; Kipp, Tobias


    The optical properties of single colloidal semiconductor nanoparticles (NPs) are considerably influenced by the direct environment of the NPs. Here, the influence of different liquid and solid glycol matrices on CdSe-based NPs is investigated. Since the fluorescence of individual NPs varies from one NP to another, it is highly desirable to study the very same individual NPs in different matrices. This was accomplished by immobilizing NPs in a liquid cell sample holder or in microfluidic devices. The samples have been investigated by space-resolved wide-field fluorescence microscopy and energy- and time-resolved confocal scanning fluorescence microscopy with respect to fluorescence intensities, emission energies, blinking behavior, and fluorescence decay dynamics of individual NPs. During the measurements the NPs were exposed to air, to liquid ethylene glycols H(OCH2CH2)nOH (also called EGn) with different chain lengths (1 ≤ n ≤ 7), to liquid 2-methylpentane-2,3-diol, or to solid polyethylene oxide. It was found that EG6-7 (also known as PEG 300) is very well suited as a liquid matrix or solvent for experiments that correlate chemical and physical modifications of the surface and of the immediate environment of individual NPs to their fluorescence properties since it leads to intense and stable fluorescence emission of the NPs. PMID:24788878

  4. Ethylene glycol-assisted coating of titania on nanoparticles.


    Dahl, Michael; Castaneda, Fernando; Joo, Ji Bong; Reyes, Victor; Goebl, James; Yin, Yadong


    Coating titania shells onto sub-micron sized particles has been widely studied recently, with success mainly limited to objects with sizes above 50 nm. Direct coating on particles below this size has been difficult to attain especially with good control over properties such as thickness and crystallinity. Here we demonstrate that titanium-glycolate formed by reacting titanium alkoxide and ethylene glycol is an excellent precursor for coating titania on aqueous nanoparticles. The new coating method is particularly useful for its ability to coat materials lacking strong polymers or ligands which are frequently needed to facilitate typical titania coatings. We demonstrate the effectiveness of the process of coating titania on metal nanoparticles ranging from citrate-stabilized gold and silver spheres to gold nanorods and silver nanoplates, and larger particles such as SiO2 microspheres and polymer spheres. Further the thickness of these coatings can be tuned from a few nanometers to ∼40 nm through sequential coatings. These coatings can subsequently be crystallized into TiO2 through refluxing in water or by calcination to obtain crystalline shells. This procedure can be very useful for the production of TiO2 coatings with tunable thickness and crystallinity as well as for further study on the effect of TiO2 coatings on nanoparticles. PMID:26673403

  5. Testicular toxicity produced by ethylene glycol mononmethyl and monoethyl ethers in the rat

    SciTech Connect

    Foster, P.M.D.; Creasy, D.M.; Foster, J.R.; Gray, T.J.B.


    Ethylene glycol monomethyl ether (EGME) and ethylene glycol monoethyl ether (EGEE) were administered orally to young male rats at doses varying from 50 to 500 mg/kg/day and 250 to 1000 mg/kg/day EGME and EGEE, respectively, for 11 days. At sequential times animals were killed and testicular histology examined. The initial and major site of damage following EGME treatment was restricted to the primary spermatocytes undergoing post-zygotene meiotic maturation and division. EGEE produced damage of an identical nature, but a larger dose was required to elicit equivalent severity (500 mg EGEE/kg/being approximately equivalent to 100 mg EGME/kg). Additionally, within the spermatocyte population, differential sensitivity was observed depending on the precise stage of meiotic maturation: dividing (stage XIV) and early pachytene (stages I-II) > late pachytene (stages VIII-XIII) > mid-pachytene (stages III-VII). Equivalent doses of methoxyacetic acid (MAA) and ethoxyacetic acid (EAA) gave injury similar to the corresponding glycol ether. When animals were pretreated with inhibitors of alcohol metabolism followed by a testicular toxic dose of EGME (500 mg/kg), an inhibitor of alcohol dehydrogenase (pyrzaole) offered complete protection. Pretreatment with the aldehyde dehydrogenase inhibitors disulfiram or pargyline did not ameliorate the testicular toxicity of EGME. In mixed cultures of Sertoli-germ cells, MAA and not EGME produced effects on spermatocytes analogous to that seen in vivo, at concentrations approximately equivalent to steady-state plasma levels after a single oral dose of EGME (500 mg/kg). It would seem likely that a metabolite and not EGME is responsible for the production of testicular damage. 16 references, 10 figures, 4 tables.

  6. Anaerobic Biodegradation of Ethylene Glycol within Hydraulic Fracturing Fluid

    NASA Astrophysics Data System (ADS)

    Heyob, K. M.; Mouser, P. J.


    Ethylene glycol (EG) is a commonly used organic additive in hydraulic fracturing fluids used for shale gas recovery. Under aerobic conditions, this compound readily biodegrades to acetate and CO2 or is oxidized through the glycerate pathway. In the absence of oxygen, organisms within genera Desulfovibrio, Acetobacterium, and others can transform EG to acetaldehyde, a flammable and suspected carcinogenic compound. Acetaldehyde can then be enzymatically degraded to ethanol or acetate and CO2. However, little is known on how EG degrades in the presence of other organic additives, particularly under anaerobic conditions representative of deep groundwater aquifers. To better understand the fate and attenuation of glycols within hydraulic fracturing fluids we are assessing their biodegradation potential and pathways in batch anaerobic microcosm treatments. Crushed Berea sandstone was inoculated with groundwater and incubated with either EG or a synthetic fracturing fluid (SFF) containing EG formulations. We tracked changes in dissolved organic carbon (DOC), EG, and its transformation products over several months. Approximately 41% of bulk DOC in SFF is degraded within 21 days, with 58% DOC still remaining after 63 days. By comparison, this same SFF degrades by 70% within 25 days when inoculated with sediment-groundwater microbial communities, suggesting that bulk DOC degradation occurs at a slower rate and to a lesser extent with bedrock. Aerobic biodegradation of EG occurs rapidly (3-7 days); however anaerobic degradation of EG is much slower, requiring several weeks for substantial DOC loss to be observed. Ongoing experiments are tracking the degradation pathways of EG alone and in the presence of SFF, with preliminary data showing incomplete glycol transformation within the complex hydraulic fracturing fluid mixture. This research will help to elucidate rates, processes, and pathways for EG biodegradation and identify key microbial taxa involved in its degradation.

  7. The effect of ethylene glycol on the phytovolatilization of 1,4-dioxane.


    Edwards, Maureen R A; Hetu, Marie-France; Columbus, Melanie; Silva, Anthony; Lefebvre, Daniel D


    Phytoremediation at contaminated sites is often complicated by the presence of more than one chemical However, the effects of common co-contaminants such as ethylene glycol on the phytoremediation of other chemicals, e.g., 1,4-dioxane, is not well understood. Field studies with DN34 poplar trees revealed a 28% decline in growth rate in response to 10 g/L ethylene glycol in the groundwater, thus indicating a significant and deleterious effect on tree viability, and likely, the plants' utility for phytoremediation. Thorough investigations using Arabidopsis thaliana, with its small size and rapid life cycle, indicated significant growth reduction at 10 g/L and complete inhibition of germination at 40 g/L ethylene glycol Ethylene glycol was almost as severe a stressor as the well characterized osmotic inhibitor, sorbitoL Watering potted trees with 10 g/L ethylene glycol reduced their growth by more than 50%, and similar results were observed in hydroponically grown poplar and willow trees. Under hydroponic conditions, 60 g/L ethylene glycol inhibited the phytovolatilization of l,4-dioxane by more than 80%, and all trees evapo-transpired 1,4-dioxane less efficiently than water. In fact, this efficiency differed between trees and the difference became more pronounced in the presence of ethylene glycol. PMID:21972497

  8. Nano-structured Platinum-based Catalysts for the Complete Oxidation of Ethylene Glycol and Glycerol

    NASA Astrophysics Data System (ADS)

    Falase, Akinbayowa

    Direct alcohol fuel cells are a viable alternative to the traditional hydrogen PEM fuel cell. Fuel versatility, integration with existing distribution networks, and increased safety when handling these fuels increases their appeal for portable power applications. In order to maximize their utility, the liquid fuel must be fully oxidized to CO2 so as to harvest the full amount of energy. Methanol and ethanol are widely researched as potential fuels to power these devices, but methanol is a toxic substance, and ethanol has a much lower energy density than other liquids such as gasoline or glucose. Oxidation of complex fuels is difficult to realize, due to difficulty in breaking carbon-carbon bonding and poisoning of the catalysts by oxidative byproducts. In order to achieve the highest efficiency, an anode needs to be engineered in such a way as to maximize activity while minimizing poisoning effects of reaction byproducts. We have engineered an anode that uses platinum-based catalysts that is capable of completely oxidizing ethylene glycol and glycerol in neutral and alkaline media with little evidence of CO poisoning. We have constructed a hybrid anode consisting of a nano-structured PtRu electrocatayst with an NAD-dependent alcohol dehydrogenase for improved oxidation of complex molecules. A nano-structured PtRu catalyst was used to oxidize ethylene glycol and glycerol in neutral media. In situ infrared spectroscopy was used to verify complete oxidation via CO2 generation. There was no evidence of poisoning by CO species. A pH study was performed to determine the effect of pH on oxidative current. The peak currents did not trend at 60 mV/pH unit as would be expected from the Nernst equation, suggesting that adsorption of fuel to the surface of the electrode is not an electron-transfer step. We synthesized nano-structured PtRu, PtSn, and PtRuSn catalysts for oxidation of ethylene glycol and glycerol in alkaline media. The PtRu electrocatalyst the highest oxidative

  9. Ethylene glycol exposure: an evidence-based consensus guideline for out-of-hospital management.


    Caravati, E Martin; Erdman, Andrew R; Christianson, Gwenn; Manoguerra, Anthony S; Booze, Lisa L; Woolf, Alan D; Olson, Kent R; Chyka, Peter A; Scharman, Elizabeth J; Wax, Paul M; Keyes, Daniel C; Troutman, William G


    ). Patients with clinically significant mucous membrane irritation should be referred for evaluation (Grade D). (3) Decontamination of dermal exposures should include routine cleansing with mild soap and water. Removal of contact lenses and immediate irrigation with room temperature tap water is recommended for ocular exposures. All patients with symptoms of eye injury should be referred for an ophthalmologic exam (Grade D). (4) Patients with symptoms of ethylene glycol poisoning should be referred immediately for evaluation regardless of the reported dose (Grade C). (5) The absence of symptoms shortly after ingestion does not exclude a potentially toxic dose and should not be used as a triage criterion (Grade C). (6) Adults who ingest a "swallow" (10-30 mL), children who ingest more than a witnessed taste or lick, or if the amount is unknown of most ethylene glycol products should be referred immediately for evaluation. The potential toxic volume of dilute solutions (e.g., concentration <20%) is larger and can be estimated by a formula in the text (Grade C). (7) A witnessed taste or lick only by a child, or an adult who unintentionally drinks and then expectorates the product without swallowing, does not need referral (Grade C). (8) Referral is not needed if it has been >24 hours since a potentially toxic unintentional exposure, the patient has been asymptomatic, and no alcohol was co-ingested (Grade D). (9) Gastrointestinal decontamination with ipecac syrup, gastric lavage or activated charcoal is not recommended. Transportation to an emergency department should not be delayed for any decontamination procedures (Grade D). (10) Patients meeting referral criteria should be evaluated at a hospital emergency department rather than a clinic. A facility that can quickly obtain an ethylene glycol serum concentration and has alcohol or fomepizole therapy available is preferred. This referral should be guided by local poison center procedures and community resources (Grade D). (11

  10. The effects on the rat testis of single inhalation exposures to ethylene glycol monoalkyl ethers, in particular ethylene glycol monomethyl ether.


    Samuels, D M; Doe, J E; Tinston, D J


    The effects of a single inhalation exposure to the rat of the saturated vapours derived from four ethylene glycol monoalkyl ethers have been investigated. No effects on the testis were observed following exposure to ethylene glycol isopropyl ether (EG ISOPE) and ethylene glycol butyl ether (EGBE), but there were marked reductions in testicular weight 14 days after exposure to ethylene glycol monomethyl ether (EGME) and ethylene glycol monoethyl ether (EGEE). Further studies were designed to establish the effect of a single exposure to EGME. Mature male albino rats were exposed to various levels of EGME vapour for a single 4-h period and killed 14 days later. Following this single exposure a dose-related decrease in testis weight was observed in rats exposed to 5,000, 2,500 or 1,250 ppm EGME. Histopathological examination revealed disordered spermatogenesis and tubular atrophy in these animals. Minimal degenerative changes were seen in the testis of rats exposed to 625 ppm EGME. When rats were examined at various time intervals after exposure to EGME vapour for 4 h, testis weight was reduced in rats examined 2 days after exposure to 2,500 and 1,000 ppm EGME and remained depressed when compared with control values for up to 19 days following exposure. Histopathological examination of the testis revealed disordered spermatogenesis in exposed animals evident at 1 day following exposure to either 2,500 or 1,00 ppm EGME. PMID:6595980

  11. Biodegradation of Ethylene Glycol by a Salt-Requiring Bacterium1

    PubMed Central

    Gonzalez, Carlos F.; Taber, Willard A.; Zeitoun, M. A.


    A gram-negative nonmotile rod which was capable of using 1,2-14C-ethylene glycol as a sole carbon source for growth was isolated from a brine pond, Great Salt Lake, Utah. The bacterium (ATCC 27042) required at least 0.85% NaCl for growth and, although the chloride ion was replaceable by sulfate ion, the sodium ion was not replaceable by potassium ion. The maximal concentration of salt tolerated for growth was approximately 12%. The bacterium was oxidase-negative when N,N-dimethyl-p-phenylenediamine was used and weakly positive when N,N,N′,N′-tetramethyl-p-phenylenediamine was used. It grows on many sugars but does not ferment them, it does not have an exogenous vitamin requirement, and it possesses a guanine plus cytosine ratio of 64.3%. Incorporation of ethylene glycol carbon into cell and respired CO2 was quantitated by use of radioactive ethylene glycol and a force-aerated fermentor. Glucose suppressed ethylene glycol metabolism. Cells grown on ethylene and propylene glycol respired ethylene glycol in a Warburg respirometer more rapidly than cells grown on glucose. Spectrophotometric evidence was obtained for oxidation of glycolate to glyoxylate by a dialyzed cell extract. PMID:4568254

  12. Ethylene glycol poisoning in three dogs: Importance of early diagnosis and role of hemodialysis as a treatment option.


    Schweighauser, A; Francey, T


    Poisoning with ethylene glycol as contained in antifreeze can rapidly lead to irreversible acute renal failure and other organ damage. It carries a grave prognosis unless diagnosed early and adequate treatment is initiated within 8 hours of ingestion. Toxicity of ethylene glycol is related to the production of toxic metabolites by the enzyme alcohol dehydrogenase (ADH), leading to early signs of severe polyuria (PU) and polydipsia (PD), gastritis, ataxia and central nervous depression, followed by progressive dehydration, and ultimately oligoanuric renal failure. In addition to general supportive care, therapeutic interventions must include either antidotes blocking ADH-mediated metabolism or blood purification techniques to remove both the parent compound and the toxic metabolites. The goal of this case report is to describe three cases of acute antifreeze intoxication in dogs, and to discuss treatment options available for this poisoning. PMID:27145686

  13. Features of anodic niobium oxide formation in aqueous-organic electrolyte solutions (influence of ethylene glycol)

    SciTech Connect

    Bairachnyi, B.I.; Gomozov, V.P.; Lyashok, L.V.; Glagolev, S.E.


    The formation of anodic oxide films (AOFs) on valve metals in electrolytes with different compositions has received little attention. Earlier investigations dealt mainly with AOF growth and properties in aqueous solutions of mineral and organic acids and salts. Less research was done on electrolytes containing aqueous-organic solvents. An empirically formulated electrolyte with a water/ethylene glycol mixture as the solvent is widely employed in forming the dielectric for semiconductor oxide capacitors (SOCs). The mechanism by which ethylene glycol acts on AOF properties is still not wholly clear. It has been found that AOFs produced in an ethylene glycol electrolyte are bilaminar, with the outer layer being less corrosion-resistant. The degradation resistance and crystalline phase content of AOFs have also been studied. The objective of the present study was to examine the effect of ethylene glycol as solvent on AOF formation on niobium.

  14. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (External Review Draft)

    EPA Science Inventory

    EPA has conducted a peer review of the scientific basis supporting the human health hazard and dose-response assessment of ethylene glycol monobutyl ether that will appear on the Integrated Risk Information System (IRIS) database.

  15. Micropallet arrays with poly(ethylene glycol) walls.


    Wang, Yuli; Salazar, Georgina To'a; Pai, Jeng-Hao; Shadpour, Hamed; Sims, Christopher E; Allbritton, Nancy L


    Arrays of releasable micropallets with surrounding walls of poly(ethylene glycol) (PEG) were fabricated for the patterning and sorting of adherent cells. PEG walls were fabricated between the SU-8 pallets using a simple, mask-free strategy. By utilizing the difference in UV-transmittance of glass and SU-8, PEG monomer was selectively photopolymerized in the space surrounding the pallets. Since the PEG walls are composed of a cross-linked structure, the stability of the walls is independent of the pallet array geometry and the properties of the overlying solution. Even though surrounded with PEG walls, the individual pallets were detached from the array by the mechanical force generated by a focused laser pulse, with a release threshold of 6 microJ. Since the PEG hydrogels are repellent to protein adsorption and cell attachment, the walls localized cell growth to the pallet top surface. Cells grown in the microwells formed by the PEG walls were released by detaching the underlying pallet. The released cells/pallets were collected, cultured and clonally expanded. The micropallet arrays with PEG walls provide a platform for performing single cell analysis and sorting on chip. PMID:18432343

  16. Crystallization studies of polyethylene -poly(ethylene glycol) graft copolymers

    NASA Astrophysics Data System (ADS)

    Mark, P. R.; Hovey, G. E.; Murthy, N. S.; Breitenkamp, K.; Kade, M.; Emerick, T.


    Structure and crystallization behavior of three copolymers obtained by grafting poly (ethylene glycol) (PEG) chains to polyethylene (PE) main chain was investigated by variable temperature x-ray diffraction and thermal analysis. The results show that PEG side chains and PE main chains crystallize into separate domains. This is especially true when grafted chains are long (50 and 100 repeat units), in which the PEG domains are same as in PEG homopolymer both in structure and in melting behavior. In the copolymer with shorter chains (25 repeat units), the PEG crystals are not distinct and melting is broad. The PEG domains can be dissolved in water or ethanol without altering the mechanical integrity of the film. PE crystallites in both samples are similar to that in PE homopolymer. For instance, the thermal expansion of the basal cell plane (a- and b-axes) of the PE domains agrees well with that of PE homopolymer over the entire temperature range from ambient to melt. However, the chain-axis dimension PE-lattice in the copolymer is shorter by ˜ 0.05 å and the basal dimensions are larger by ˜ 0.05 å. The changes in these dimensions due to the changes in the length of the grafted PEG chains were investigated.

  17. Mechanical properties of layered poly (ethylene glycol) gels.


    Skornia, S L; Bledsoe, J G; Kelso, B; Kuntz Willitz, R


    Poly(ethylene glycol) (PEG) hydrogels have become a popular material for biomedical applications because of their versatility in use and design. As these gels are readily crosslinked under UV, microfabrication techniques have been investigated to manufacture complex three dimensional structures to better mimic the in vivo environment. This work investigated whether a layering technique to fabricate gels offered sufficient strength between the layers to perform similarly in mechanical testing to unlayered gels. Two mechanical tests were performed: tensile tests and peel tests. The tensile tests, which examined sample gels whose test sections were crosslinked for different durations, demonstrated no statistical differences in elastic modulus between sample and control gels. As expected, a statistical increase in the elastic modulus was found with increased PEG concentration. Comparison of the yield stress between samples and controls illustrated differences with total crosslinking duration, which may be due to the decreased molecular weight of the chains with decreased crosslinking time. In peel tests, no statistical differences of maximum peel force were found between samples and controls. However, an increase in the maximum peel force was found with increasing concentration of PEG. Overall, this study demonstrates that the layering process described for the PEG gels has minimal impact on the tested mechanical properties of the system. As mechanical properties are critical to the design of tissue engineered devices, these results demonstrate that this fabrication method may be appropriate for further study as a scaffold for complex cellular systems. PMID:20799187

  18. Diffusion characteristics of ethylene glycol in skeletal muscle.


    Oliveira, Luís M; Carvalho, Maria Inês; Nogueira, Elisabete M; Tuchin, Valery V


    Part of the optical clearing study in biological tissues concerns the determination of the diffusion characteristics of water and optical clearing agents in the subject tissue. Such information is sufficient to characterize the time dependence of the optical clearing mechanisms—tissue dehydration and refractive index (RI) matching. We have used a simple method based on collimated optical transmittance measurements made from muscle samples under treatment with aqueous solutions containing different concentrations of ethylene glycol (EG), to determine the diffusion time values of water and EG in skeletal muscle. By representing the estimated mean diffusion time values from each treatment as a function of agent concentration in solution, we could identify the real diffusion times for water and agent. These values allowed for the calculation of the correspondent diffusion coefficients for those fluids. With these results, we have demonstrated that the dehydration mechanism is the one that dominates optical clearing in the first minute of treatment, while the RI matching takes over the optical clearing operations after that and remains for a longer time of treatment up to about 10 min, as we could see for EG and thin tissue samples of 0.5 mm. PMID:25525766

  19. Partitioning of differently sized poly(ethylene glycol)s into OmpF porin.

    PubMed Central

    Rostovtseva, Tatiana K; Nestorovich, Ekaterina M; Bezrukov, Sergey M


    To understand the physics of polymer equilibrium and dynamics in the confines of ion channel pores, we study partitioning of poly(ethylene glycol)s (PEGs) of different molecular weights into the bacterial porin, OmpF. Thermodynamic and kinetic parameters of partitioning are deduced from the effects of polymer addition on ion currents through single OmpF channels reconstituted into planar lipid bilayer membranes. The equilibrium partition coefficient is inferred from the average reduction of channel conductance in the presence of PEG; rates of polymer exchange between the pore and the bulk are estimated from PEG-induced conductance noise. Partition coefficient as a function of polymer weight is best fitted by a "compressed exponential" with the compression factor of 1.65. This finding demonstrates that PEG partitioning into the OmpF channel pore has sharper dependence on polymer molecular weight than predictions of hard-sphere, random-flight, or scaling models. A 1360-Da polymer separates regimes of partitioning and exclusion. Comparison of its characteristic size with the size of a 2200-Da polymer previously found to separate these regimes for the alpha-toxin shows good agreement with the x-ray structural data for these channels. The PEG-induced conductance noise is compatible with the polymer mobility reduced inside the OmpF pore by an order of magnitude relatively to its value in bulk solution. PMID:11751305

  20. Microwave spectrum and internal rotations of ethylene glycol. I. Glycol-O-d2

    NASA Astrophysics Data System (ADS)

    Walder, E.; Bauder, A.; Günthard, Hs. H.


    The microwave spectrum of a dideuterated form of ethylene glycol (glycol-O-d2, CH2ODCH2OD) has been investigated in the frequency range from 18 to 50 GHz. Among the many transitions observed, 64 rotational transitions could be assigned with the help of microwave—microwave double resonance experiments. All transitions occurred as doublets due to large amplitude motions in the molecule. A semirigid molecular model which features a collective concerted internal rotation of the two OD groups on the Born—Oppenheimer surface has been used for the assignment and analysis. This model allowed a satisfactory interpretation of the assigned transitions. From the centers of the doublets the following rotational constants and the dipole moment of a hypothetical rigid rotor could be determined: A = 14394.63(17) MHz, B = 5276.27(24) MHz, C = 4323.53(20) MHz, μa = 2.166(37)D, μb = 0.74(18)D, and μc = 0.75(21)D. An empirical potential function for the concerted internal rotation of the OD groups has been derived from the measured doublet splittings.

  1. [Determination of ethylene glycol in biological fluids--propylene glycol interferences].


    Gomółka, Ewa; Cudzich-Czop, Sylwia; Sulka, Adrianna


    Many laboratories in Poland do not use gas chromatography (GC) method for determination of ethylene glycol (EG) and methanol in blood of poisoned patients, they use non specific spectrophotometry methods. One of the interfering substances is propylene glycol (PG)--compound present in many medical and cosmetic products: drops, air freshens, disinfectants, electronic cigarettes and others. In Laboratory of Analytical Toxicology and Drug Monitoring in Krakow determination of EG is made by GC method. The method enables to distinguish and make resolution of (EG) and (PG) in biological samples. In the years 2011-2012 in several serum samples from diagnosed patients PG was present in concentration from several to higher than 100 mg/dL. The aim of the study was to estimate PG interferences of serum EG determination by spectrophotometry method. Serum samples containing PG and EG were used in the study. The samples were analyzed by two methods: GC and spectrophotometry. Results of serum samples spiked with PG with no EG analysed by spectrophotometry method were improper ("false positive"). The results were correlated to PG concentration in samples. Calculated cross-reactivity of PG in the method was 42%. Positive results of EG measured by spectrophotometry method must be confirmed by reference GC method. Spectrophotometry method shouldn't be used for diagnostics and monitoring of patients poisoned by EG. PMID:24466683

  2. Molecular interactions and structures in ethylene glycol-ethanol and ethylene glycol-water solutions at 303 K on densities, viscosities, and refractive indices data

    NASA Astrophysics Data System (ADS)

    Deosarkar, S. D.; Ghatbandhe, A. S.


    Molecular interactions and structural fittings in binary ethylene glycol + ethanol (EGE, x EG = 0.4111-0.0418) and ethylene glycol + water (EGW, x EG = 0.1771-0.0133) mixtures were studied through the measurement of densities (ρ), viscosities (η), and refractive indices ( n D ) at 303.15 K. Excess viscosities (η E ), molar volumes ( V m ), excess molar volumes ( V {/m E }), and molar retractions ( R M ) of the both binary systems were computed from measured properties. The measured and computed properties have been used to understand the molecular interactions in unlike solvents and structural fittings in these binary mixtures.

  3. Clinical Features of Reported Ethylene Glycol Exposures in the United States

    PubMed Central

    Jobson, Meghan A.; Hogan, Susan L.; Maxwell, Colin S.; Hu, Yichun; Hladik, Gerald A.; Falk, Ronald J.; Beuhler, Michael C.; Pendergraft, William F.


    Background Ethylene glycol is highly toxic and represents an important cause of poisonings worldwide. Toxicity can result in central nervous system dysfunction, cardiovascular compromise, elevated anion gap metabolic acidosis and acute kidney injury. Many states have passed laws requiring addition of the bittering agent, denatonium benzoate, to ethylene glycol solutions to reduce severity of exposures. The objectives of this study were to identify differences between unintentional and intentional exposures and to evaluate the utility of denatonium benzoate as a deterrent. Methods and Findings Using the National Poison Data System, we performed a retrospective analysis of reported cases of ethylene glycol exposures from January 2006 to December 2013. Outcome classification was summed for intentionality and used as a basis for comparison of effect groups. There were 45,097 cases of ethylene glycol exposures resulting in 154 deaths. Individuals more likely to experience major effects or death were older, male, and presented with more severe symptoms requiring higher levels of care. Latitude and season did not correlate with increased exposures; however, there were more exposures in rural areas. Denatonium benzoate use appeared to have no effect on exposure severity or number. Conclusion Deaths due to ethylene glycol exposure were uncommon; however, there were major clinical effects and more exposures in rural areas. Addition of denatonium benzoate was not associated with a reduction in exposures. Alternative means to deter ingestion are needed. These findings suggest the need to consider replacing ethylene glycol with alternative and less toxic agents. PMID:26566024

  4. Mutagenicity of ethylene glycol ethers and of their metabolites in Salmonella typhimurium his-.


    Hoflack, J C; Lambolez, L; Elias, Z; Vasseur, P


    Ethylene glycol ethers, their aldehyde and their acid metabolites were evaluated for their mutagenicity with the Ames test. The Salmonella typhimurium his- tester strains TA 97a, TA 98, TA 100 and TA 102 were used with and without rat S9 mix. Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol n-butyl ether and their corresponding aldehyde and acid derivatives were tested up to 10(-4) mol/plate (around 10 mg/plate) or up to cytotoxic concentrations. All tested substances gave negative results with TA 98, TA 100 and TA 102 either with or without S9 mix. In contrast, ethylene glycol n-butyl ether (EGBE) and the aldehyde metabolite of ethylene glycol monomethyl ether, methoxyacetaldehyde (MALD), displayed mutagenic potency in strain TA 97a with and without S9 mix at high concentrations. A significant number of revertants was obtained from 19 mumol/plate EGBE (2.2 mg/plate) and from 34 mumol/plate MALD (2.5 mg/plate). At these concentrations the level of revertants reached up to 7-fold and 3-fold the control values for EGBE and MALD respectively. PMID:7531287

  5. Synthesis of Monodispersed Tantalum(V) oxide Nanospheres by an Ethylene Glycol Mediated Route

    EPA Science Inventory

    Tantalum(V) oxide (Ta2O5) nanospheres have been synthesized by a very simple ethylene glycol mediated route. The two-step process involves the formation of glycolate nanoparticles and their subsequent hydrolysis and calcination to generate the final Ta2O5 nanospheres. The synthes...

  6. A study of ethylene glycol exposure and kidney function of aircraft de-icing workers.


    Gérin, M; Patrice, S; Bégin, D; Goldberg, M S; Vyskocil, A; Adib, G; Drolet, D; Viau, C


    Ethylene glycol levels were measured in 154 breathing zone air samples and in 117 urine samples of 33 aviation workers exposed to de-icing fluid (basket operators, de-icing truck drivers, leads and coordinators) studied during 42 worker-days over a winter period of 2 months at a Montreal airport. Ethylene glycol as vapour did not exceed 22 mg/m3 (mean duration of samples 50 min). Mist was quantified at higher levels in 3 samples concerning 1 coordinator and 2 basket operators (76-190 mg/m3, 45-118 min). In 16 cases workers' post-shift or next-morning urine contained quantities of ethylene glycol exceeding 5 mmol/mol creatinine (up to 129 mmol/mol creatinine), with most of these instances occurring in basket operators and coordinators, some of whom did not wear paper masks and/or were accidentally sprayed with de-icing fluid. Diethylene glycol was also found in a few air and urinary samples at levels around one tenth those of ethylene glycol. Urinary concentrations of albumin, beta-N-acetyl-glucosaminidase, beta-2-microglobulin and retinol-binding protein were measured and compared over various periods, according to subgroups based on exposure level and according to the frequency of extreme values. These analyses did not demonstrate acute or chronic kidney damage that could be attributed to working in the presence of ethylene glycol. In conclusion, this study does not suggest important health effects of exposure to de-icing fluid in this group of workers. Potential for overexposure exists, however, in certain work situations, and recommendations on preventive measures are given. In addition, these results suggest that other routes of absorption than inhalation, such as the percutaneous route, may be important and that urinary ethylene glycol may be a useful indicator of exposure to ethylene glycol. PMID:9138000

  7. CH2-units on (poly-)ethylene glycol radially dehydrate cytoplasm of resting skinned skeletal muscle.


    Kimura, Masako; Takemori, Shigeru


    Observing the optical cross-section and electron micrographs of mechanically skinned fibres of frog skeletal muscle, we found that ethylene glycols (EGs) of small (mono-, di-, tri- and tetra-EGs; M(r) 62-194) and medium (poly-EGs; M(r) 900 and 3350) molecular weights efficiently dehydrate the fibres to shrink them radially without microscopic inhomogeneity. The medium-sized poly-EGs at 30% weight/weight concentration absorbed almost all the evaporable water from the fibre. Passive tension measurement at near slack sarcomere spacing indicated that this dehydration by EGs did not accompany longitudinal fibre shrinkage. Chemically relevant fully hydric alcohols (glycerol, threitol, ribitol and mannitol; M(r) 92-182) showed no appreciable dehydrating ability on fibres. An intimate correlation was found between fibre dehydration and CH(2)-concentration of the solutions. Viscosity measurements indicated that the hydrodynamic radii of the alcohols were comparable to those of the small EGs. Therefore, hydrodynamic radii are not a primary determinant of the dehydrating ability. Additionally, CH(2)-concentration of EGs but not alcohols was found to correlate intimately with the measured viscosity of the bulk solution of EGs. These results suggested that the interaction between water molecules and CH(2)-units in crowded cytoplasm of skeletal muscle affects cytoplasm as a whole to realize anisotropic fibre shrinkage. PMID:18583358

  8. Photochemical reactions of photosystem II in ethylene glycol.


    Hillier, W; Lukins, P; Seibert, M; Wydrzynski, T


    The behavior of photosystem II (PSII) reactions was investigated under conditions of decreasing water content by the addition of increasing concentrations of ethylene glycol (EG). The photosynthetic activities were measured for PSII samples either directly in aqueous solutions of EG or in the standard buffer medium following EG treatment. Several effects on PSII arise upon exposure to EG. Below 50% EG there are no significant irreversible changes, although there is a slowing of the QA-reoxidation kinetics in the presence of EG. At concentrations of 50-70% EG, protein structural changes occur that include the release of the 16, 23, and 33 kDa extrinsic proteins and two of the catalytic Mn ions. For these samples, the capacity for O2 evolution is considerably reduced and the formation of donor side H2O2 is enhanced. In 60% EG, the nanosecond components in the rate of P680+ reduction are converted entirely to microsecond kinetics which upon return of the sample to the standard buffer medium are partially restored, indicating that EG has a reversible, solvent effect on the PSII donor side. At concentrations of EG > 70% chlorophyll fluorescence measurements reveal reversible increases in the FO level concomitant with the generation and disappearance of a 5 microseconds decay component in the P680+ reduction kinetics. This result may indicate a solvent-induced uncoupling of the light harvesting pigment bed from the reaction center complex. As the EG concentration is increased to 80-100%, there is an irreversible loss of the primary charge separation. The use of EG as a cryoprotectant and as a water-miscible organic solvent for PSII is discussed. PMID:8993320

  9. Ethylene glycol ethers and risks of spontaneous abortion and subfertility.


    Correa, A; Gray, R H; Cohen, R; Rothman, N; Shah, F; Seacat, H; Corn, M


    Potential reproductive effects from occupational exposures to ethylene glycol ethers (EGE) are of concern since these organic solvents have been used widely in industry, and their reproductive toxicity has been well documented in animal studies. For determination of whether occupational exposure to EGE was associated with increased risks of spontaneous abortion and subfertility (i.e., taking more than 1 year of unprotected intercourse to conceive), a retrospective cohort study was conducted among workers at two semiconductor manufacturing plants in the eastern United States in 1980-1989 as part of a larger evaluation of reproductive health. Reproductive and occupational histories were obtained from interviews of semiconductor manufacturing workers and spouses. Assessment of potential exposure to mixtures containing EGE (none, low, medium, and high) was based on reported processes and company records. There were 1,150 pregnancies to semiconductor manufacturers, 561 to female employees and 589 to wives of male employees. Among female manufacturers, potential exposure to mixtures containing EGE was associated with increased risks of spontaneous abortion (relative risk in the high exposure group = 2.8; 95% confidence interval (CI) 1.4-5.6) and subfertility (odds ratio in the high exposure group = 4.6; 95% CI 1.6-13.3). Both of these risks exhibited a dose-response relation with potential EGE exposure (p for trend = 0.02). Among spouses of male manufacturers potentially exposed to mixtures containing EGE, there was no increased risk of spontaneous abortion, but there was a nonsignificant increased risk of subfertility (odds ratio in the high exposure group = 1.7; 95% CI 0.7-4.3). PMID:8651233

  10. Comparison of Ethylene Glycol and Propylene Glycol for the Vitrification of Immature Porcine Oocytes

    PubMed Central

    SOMFAI, Tamás; NAKAI, Michiko; TANIHARA, Fuminori; NOGUCHI, Junko; KANEKO, Hiroyuki; KASHIWAZAKI, Naomi; EGERSZEGI, István; NAGAI, Takashi; KIKUCHI, Kazuhiro


    Abstract Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After warming, the COCs were in vitro matured (IVM), and surviving oocytes were in vitro fertilized (IVF) and cultured. The mean survival rate of vitrified oocytes in 35% PG (73.9%) was higher (P<0.05) than that in 35% EG (27.8%). Oocyte maturation rates did not differ among vitrified and non-vitrified control groups. Blastocyst formation in the vitrified EG group (10.8%) was higher (P<0.05) than that in the vitrified PG group (2.0%) but was lower than that in the control group (25.0%). Treatment of oocytes with 35% of each cryoprotectant without vitrification revealed a higher toxicity of PG on subsequent blastocyst development compared with EG. The combination of EG and PG resulted in 42.6% survival after vitrification. The maturation and fertilization rates of the surviving oocytes were similar in the vitrified, control and toxicity control (TC; treated with EG+PG combination without cooling) groups. Blastocyst development in the vitrified group was lower (P<0.05) than that in the control and TC groups, which in turn had similar development rates (10.7%, 18.1% and 23.3%, respectively). In conclusion, 35% PG enabled a higher oocyte survival rate after vitrification compared with 35% EG. However, PG was greatly toxic to oocytes. The combination of 17.5% EG and 17.5% PG yielded reasonable survival rates without toxic effects on embryo development. PMID:23666455

  11. Fluorescein prototropism within poly(ethylene glycol)s and their aqueous mixtures.


    Bhagi, Ambika; Pandey, Shubha; Pandey, Ashish; Pandey, Siddharth


    Depending on the solubilizing milieu and conditions, fluorescein may exist in one or more of its many prototropic forms [cationic, neutral (zwitterionic, quinoid, and lactone), monoanionic (phenolate and carboxylate), and dianionic]. Fluorescein prototropism is investigated in liquid poly(ethylene glycol)s (PEGs) of different average molecular weight (MW) and their aqueous mixtures using UV-vis absorbance along with static and time-resolved fluorescence spectroscopic techniques. Information regarding various prototropic forms of fluorescein in up to 30 wt % different average MW PEG-added aqueous buffers at varying pH reveals that addition of PEG causes lactonization of fluorescein in the milieu; higher the average MW of PEG, the more the lactonization is. Neat PEG200, PEG400, and PEG600 are found to support the dianionic form of fluorescein, while PEG1000 supports the neutral lactonized form. It is demonstrated that various prototropic forms of fluorescein may be generated within PEGs by addition of adequate amounts of acidic aqueous buffer. Significant bathochromic shift in absorbance and fluorescence band maxima of dianionic fluorescein as concentration of PEG200 is increased correlates well with hydrogen bond accepting basicity, hydrogen bond donating acidity, and dipolarity/polarizability of the aqueous PEG200 mixture. Interestingly, fluorescence emission from the cationic form of fluorescein is observed from dilute aqueous acidic media in the presence of high concentration of PEG200, whereas the fluorescence emission from cation in the absence of PEG200 is observed only from aqueous solutions of very high acidity (>5 M [H(+)]). Excited-state intensity decay is also used to support this outcome. It is proposed that, in the presence of a small amount of acid in PEG200, a highly acidic water-rich solvation microenvironment is formed around fluorescein, which converts its dianionic form to cationic form and considerably hinders the rapid deprotonation of the

  12. Potentiation of aquatic pollution by ethylene glycol with regard to the aquatic angiosperm, Lemna gibba

    SciTech Connect

    Thomas, D.A.; Barber, J.T.; Yatsu, L.Y.; Ensley, H.E.


    Ethylene glycol is usually thought of as a benign component of urban runoff. Thus, its EC50 value, with regard to the vegetative growth of axenically grown Lemna gibba, is relatively high, viz. 164 mM. Ethylene glycol is not metabolized by Lemna but growth is demonstrably stimulated at concentrations below 75 mM. In the presence of ethylene glycol, the fronds of duckweed are dark green, translucent and the growth medium contains gas bubbles of carbon dioxide which result from an enhanced uptake of sucrose from the growth medium and its subsequent respiration. The uptake is a non-specific effect since the uptake of various other compounds, including water, is enhanced when duckweed is grown in the presence of ethylene glycol. The increased uptake of water, sucrose, inorganic ions and organic compounds results from an increased permeability due to the creation of intercellular holes in the aerenchymatous tissues of the ethylene glycol-treated plants. The mechanism by which ethylene glycol causes the holes is unknown but may involve a disruption in lipid metabolism since the hydrophobicity of the fronds is altered and their lipid composition is changed. The significance of this phenomenon is that toxicants, just like innocuous substances, are taken up in increased amounts by treated plants and as a result their toxicities are increased with regard to duckweed as evidenced by a decrease in their effective concentrations, often of more than 3-fold. These results suggest that although ethylene glycol itself may be benign, its presence in polluted waters containing other toxicants may potentiate the effects of those pollutants.

  13. Engineering Poly(ethylene glycol) Materials to Promote Cardiogenesis

    NASA Astrophysics Data System (ADS)

    Smith, Amanda Walker

    Heart failure is one of the leading causes of death worldwide, and the current costs of treatment put a significant economic burden on our societies. After an infarction, fibrotic tissue begins to form as part of the heart failure cascade. Current options to slow this process include a wide range of pharmaceutical agents, and ultimately the patient may require a heart transplant. Innovative treatment approaches are needed to bring down costs and improve quality of life. The possibility of regenerating or replacing damaged tissue with healthy cardiomyocytes is generating considerable excitement, but there are still many obstacles to overcome. First, while cell injections into the myocardium have demonstrated slight improvements in cardiac function, the actual engraftment of transplanted cells is very low. It is anticipated that improving engraftment will boost outcomes. Second, cellular differentiation and reprogramming protocols have not yet produced cells that are identical to adult cardiomyocytes, and immunogenicity continues to be a problem despite the advent of autologously derived induced pluripotent stem cells. This dissertation will explore biomaterials approaches to addressing these two obstacles. Tissue engineering scaffolds may improve cell engraftment by providing bioactive factors, preventing cell anoikis, and reducing cell washout by blood flow. Poly(ethylene glycol) (PEG) is often used as a coating to reduce implant rejection because it is highly resistant to protein adsorption. Because fibrosis of a material in contact with the myocardium could cause arrhythmias, PEG materials are highly relevant for cardiac tissue engineering applications. In Chapter 2, we describe a novel method for crosslinking PEG microspheres around cells to form a scaffold for tissue engineering. We then demonstrate that HL-1 cardiomyocyte viability and phenotype are retained throughout the fabrication process and during the first 7 weeks of culture. In the third chapter of the

  14. Transport properties of carbon dioxide and ammonia in water - ethylene glycol mixtures from molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Iskrenova, Eugeniya; Patnaik, Soumya S.


    The endothermic decomposition of ammonium carbamate has been proposed as a novel heat sink mechanism for aircraft thermal management (Johnson et al. SAE Technical Paper 2012-01-2190, 2012, doi:10.4271/2012-01-2190]). The products of this decomposition are carbon dioxide and ammonia which need to be efficiently removed in order to better control the decomposition reaction. Molecular dynamics simulations can provide insight into the transport properties of carbon dioxide and ammonia in the carrier fluid. In this work, an extensive set of molecular dynamics simulations was performed to better quantify the concentration dependence of solubility and diffusivity of carbon dioxide and ammonia in water, ethylene glycol, and their mixtures at standard temperature and pressure and at elevated temperature. The simulation results confirm the experimental observations that ammonia is more soluble than carbon dioxide in either water or ethylene glycol and that both carbon dioxide and ammonia are more soluble in ethylene glycol than in water. The simulations of water - ethylene glycol mixtures show that increasing the molar fraction of ethylene glycol leads to increased solubility of carbon dioxide and ammonia in the mixture. The authors gratefully acknowledge the DoD High Performance Computing Centers for computational resources.

  15. Complete free energy landscape and statistical thermodynamics of single poly(ethylene glycol) molecules

    NASA Astrophysics Data System (ADS)

    Staple, Douglas; Hanke, Felix; Kreuzer, Hans Jürgen


    In this paper, we revisit the statistical mechanics of poly(ethylene glycol) with the intention to check ad hoc approximations made in previous works, namely to keep all C O bonds along the chain in the trans configuration. The theory developed here includes all the bonds on an equal footing. Starting with density functional theory calculations for the ethylene glycol monomer, dimer and trimer one can determine all the energetic and geometric parameters needed for a rotationally isomeric state model with interactions between nearest neighbour monomers included. The properties of short molecules are presented in detail, including the force-extension curves, end-to-end distributions, and also a discussion of the local helix properties. Finally, we use the transfer matrix method for long chains of 200 ethylene glycol monomers, i.e. 600 bonds. The agreement with the experimental force-extension curve is excellent.

  16. Study of core-shell platinum-based catalyst for methanol and ethylene glycol oxidation

    NASA Astrophysics Data System (ADS)

    Kaplan, D.; Alon, M.; Burstein, L.; Rosenberg, Yu.; Peled, E.

    A Ru core-Pt shell, XC72-supported catalyst was synthesized in a two-step process: first, by deposition of Ru on XC72 by the polyol process and then by deposition of Pt on the XC72-supported Ru, with NaBH 4 as reducing agent. The structure and composition of this core-shell catalyst were determined by EDS, XPS, TEM and XRD. Electrochemical characterization was determined with the use of cyclic voltammetry and chronoamperometry. The methanol and ethylene glycol oxidation activities of the core-shell catalyst were studied at 80 °C and compared to those of a commercial catalyst. It was found to be significantly better (in terms of A g -1 of Pt) in the case of methanol oxidation and worse in the case of ethylene glycol oxidation. Possible reasons for the lower ethylene glycol oxidation activity of the core-shell catalyst are discussed.

  17. Reduction of friction stress of ethylene glycol by attached hydrogen ions

    PubMed Central

    Li, Jinjin; Zhang, Chenhui; Deng, Mingming; Luo, Jianbin


    In the present work, it is shown that the friction stress of ethylene glycol can decrease by an order of magnitude to achieve superlubricity if there are hydrogen ions attached on the friction surfaces. An ultra-low friction coefficient (μ = 0.004) of ethylene glycol between Si3N4 and SiO2 can be obtained with the effect of hydrogen ions. Experimental result indicates that the hydrogen ions adsorbed on the friction surfaces forming a hydration layer and the ethylene glycol in the contact region forming an elastohydrodynamic film are the two indispensable factors for the reduction of friction stress. The mechanism of superlubricity is attributed to the extremely low shear strength of formation of elastohydrodynamic film on the hydration layer. This finding may introduce a new approach to reduce friction coefficient of liquid by attaching hydrogen ions on friction surfaces. PMID:25428584

  18. Inhibited ethylene and propylene glycols for corrosion and freeze protection in water-based HVAC systems

    SciTech Connect

    Roo, A.M. de; Lee, B.W.


    Industrially inhibited ethylene and propylene glycols are used extensively to provide protection against equipment damage due to corrosion and freezing. This paper will describe the proper use of these glycols, including system preparation, fluid installation, and fluid maintenance. The impact of the use of these glycols on the operation of the system is discussed along with methods for overcoming any declines in heat transfer. From this discussion, it will become clear why automotive antifreeze formulations should not be used in heating, ventilating, and airconditioning (HVAC) systems. Also included are data on the physical properties of aqueous solutions of ethylene and propylene glycol, the concept of burst vs. freeze protection, typical results of corrosion tests, and methods to use to monitor the fluid for each application.

  19. Synthesis, Characterization, and Size Control of Zinc Sulfide Nanoparticles Capped by Poly(ethylene glycol)

    NASA Astrophysics Data System (ADS)

    Allehyani, S. H. A.; Seoudi, R.; Said, D. A.; Lashin, A. R.; Abouelsayed, A.


    Zinc sulfide nanoparticles with controllable size were synthesized by chemical precipitation. Results from transmission electron microscopy and x-ray powder diffraction showed the samples were grown with the cubic phase. Particle size was varied by varying the molar ratio of zinc chloride to sodium sulfide in the presence of poly(ethylene glycol). The optical band gap was calculated on the basis of ultraviolet-visible spectroscopy and ranged from 4.13 to 4.31 eV depending on particle size. Surface passivation and adsorption of poly (ethylene glycol) on the nanoparticles was explained on the basis of Fourier-transform infrared measurements.

  20. Microgels of polyaspartamide and poly(ethylene glycol) derivatives obtained by γ-irradiation

    NASA Astrophysics Data System (ADS)

    Pitarresi, Giovanna; Licciardi, Mariano; Craparo, Emanuela Fabiola; Calderaro, Elio; Spadaro, Giuseppe; Giammona, Gaetano


    The copolymer PHG based on α, β-poly( N-2-hydroxyethyl)- DL-aspartamide (PHEA) functionalized with glycidyl methacrylate has been exposed in aqueous solution to a γ-ray source at different irradiation doses (2, 2.5 and 3.5 kGy), alone or in combination with poly(ethylene glycol)dimethacrylate (PEGDMA) or poly(ethylene glycol)diacrylate (PEGDA). The irradiation produces microgel systems that have been characterized by viscosity measurements. Lyophilization of microgels gives rise to samples able to swell instantaneously in water whereas their treatment with acetone produces swellable microparticles that have been characterized.

  1. Indirect detection of ethylene glycol oligomers using a contactless conductivity detector in capillary liquid chromatography.


    Takeuchi, Toyohide; Sedyohutomo, Anang; Lim, Lee Wah


    Ethylene glycol oligomers were visualized by indirect conductimetric detection based on dilution of the mobile phase due to the analytes. A high electrical conductivity background was maintained by the addition of 5 mM sodium nitrate in the mobile phase, and the analytes were visualized by decreases in the background when they eluted. A capacitively coupled contactless conductivity detector was convenient to monitor effluents from the microcolumn with minimum extra-column band broadening. The signals as negative peaks were linear to the concentration of the analytes, and a concentration detection limit of 0.025% was achieved for tetraethylene glycol at S/N=3, corresponding to the mass detection limit of 38 ng for 0.15 microl injection. The logarithm of the retention factor of ethylene glycol oligomers was linear to the degree of polymerization (DP) as well as to the acetonitrile composition in the mobile phase. These situations allowed us to estimate the DP of eluted ethylene glycol oligomers by using a few oligomers with known DP. The dynamic reserve, defined as the ratio of the background to its noise level achieved under the present conditions, was 2.3 x 10(5) which was much larger than that achieved by UV absorption detection. The present method was applied to profile ethylene glycol oligomers contained in commercially available PEG reagents. PMID:19609021

  2. Ethylene Glycol Adsorption and Reaction over CeOX(111) Thin Films

    SciTech Connect

    Mullins, David R; Chen, Tsung-Liang


    This study reports the interaction of ethylene glycol with well-ordered CeO{sub x}(111) thin film surfaces. Ethylene glycol initially adsorbs on fully oxidized CeO{sub 2}(111) and reduced CeO{sub 2-x}(111) through the formation of one C-O-Ce bond and then forms a second alkoxy bond after annealing. On fully oxidized CeO{sub 2}(111) both recombination of ethylene glycol and water desorption occur at low temperature leaving stable -OCH{sub 2}CH{sub 2}O- (ethylenedioxy) intermediates and oxygen vacancies on the surface. This ethylenedioxy intermediate goes through C-C bond scission to produce formate species which then react to produce CO and CO{sub 2}. The formation of water results in the reduction of the ceria. On a reduced CeO{sub 2-x}(111) surface the reaction selectivity shifts toward a dehydration process. The ethylenedioxy intermediate decomposes by breaking a C-O bond and converts into an enolate species. Similar to the reaction of acetaldehyde on reduced CeO{sub 2-x}(111), the enolate reacts to produce acetaldehyde, acetylene, and ethylene. The loss of O from ethylene glycol leads to a small amount of oxidation of the reduced ceria.

  3. Ethylene Glycol Adsorption and Reaction over CeOX(111) Thin Films

    SciTech Connect

    T Chen; D Mullins


    This study reports the interaction of ethylene glycol with well-ordered CeO{sub x}(111) thin film surfaces. Ethylene glycol initially adsorbs on fully oxidized CeO{sub 2}(111) and reduced CeO{sub 2-x}(111) through the formation of one C-O-Ce bond and then forms a second alkoxy bond after annealing. On fully oxidized CeO{sub 2}(111) both recombination of ethylene glycol and water desorption occur at low temperature leaving stable -OCH{sub 2}CH{sub 2}O- (ethylenedioxy) intermediates and oxygen vacancies on the surface. This ethylenedioxy intermediate goes through C-C bond scission to produce formate species which then react to produce CO and CO{sub 2}. The formation of water results in the reduction of the ceria. On a reduced CeO{sub 2-x}(111) surface the reaction selectivity shifts toward a dehydration process. The ethylenedioxy intermediate decomposes by breaking a C-O bond and converts into an enolate species. Similar to the reaction of acetaldehyde on reduced CeO{sub 2-x}(111), the enolate reacts to produce acetaldehyde, acetylene, and ethylene. The loss of O from ethylene glycol leads to a small amount of oxidation of the reduced ceria.

  4. Green polymer chemistry VIII: synthesis of halo-ester-functionalized poly(ethylene glycol)s via enzymatic catalysis.


    Castano, Marcela; Seo, Kwang Su; Kim, Eun Hye; Becker, Matthew L; Puskas, Judit E


    Halo-ester-functionalized poly(ethylene glycol)s (PEGs) are successfully prepared by the transesterification of alkyl halo-esters with PEGs using Candida antarctica lipase B (CALB) as a biocatalyst under the solventless conditions. Transesterifications of chlorine, bromine, and iodine esters with tetraethylene glycol monobenzyl ether (BzTEG) are quantitative in less than 2.5 h. The transesterification of halo-esters with PEGs are complete in 4 h. (1) H and (13) C NMR spectroscopy with MALDI-ToF and ESI mass spectrometry confirm the structure and purity of the products. This method provides a convenient and "green" process to effectively produce halo-ester PEGs. PMID:23877930

  5. Platelet responses to dynamic biomaterial surfaces with different poly(ethylene glycol) and polyrotaxane molecular architectures constructed on gold substrates.


    Kakinoki, Sachiro; Yui, Nobuhiko; Yamaoka, Tetsuji


    Four different dynamic biomaterial surfaces with different molecular architectures were prepared using two hydrophilic polymers: poly(ethylene glycol) and polyrotaxanes containing α-cyclodextrin. Either one or both terminals of the poly(ethylene glycol) or polyrotaxanes were immobilized onto a gold substrate via Au-S bonds, resulting in poly(ethylene glycol)-graft, polyrotaxanes-graft, poly(ethylene glycol)-loop, and polyrotaxanes-loop structures. Human platelet adhesion was suppressed more effectively on the graft surfaces than on the loop surfaces for both poly(ethylene glycol) and polyrotaxanes due to the high mobility of graft polymer chains with a free terminal. Moreover, the platelets adhered to the polyrotaxane surfaces much less than the poly(ethylene glycol) surfaces, possibly because of the mobile nature of the α-cyclodextrin molecules that were threaded on the poly(ethylene glycol) chain. Actin filament assembly in adherent platelets was also greatly prevented on the poly(ethylene glycol)/polyrotaxanes-graft surfaces in comparison with the corresponding loop surfaces. A clear correlation between the numbers and areas of adherent platelets on these surfaces suggests that platelet adhesion and activation were dominated by the platelet GPIIb/IIIa-adsorbed fibrinogen interaction. These results indicate that both of the different modes of dynamic features, sliding/rotation of α-cyclodextrin and polymer chain mobility, effectively suppressed platelet adhesion in spite of the similar hydrophilicity. This research affords a novel chemical strategy for designing hemocompatible biomaterial surfaces. PMID:23048065

  6. Highly efficient conversion of biomass-derived glycolide to ethylene glycol over CuO in water.


    Xu, Lingli; Huo, Zhibao; Fu, Jun; Jin, Fangming


    The efficient conversion of biomass-derived glycolide into ethylene glycol over CuO in water was investigated. The reaction of glycolide was carried out with 25 mmol Zn and 6 mmol CuO with 25% water filling at 250 °C for 150 min, which yielded the desired ethylene glycol in 94% yield. PMID:24769741

  7. Efficient utilization of pentoses for bioproduction of the renewable two-carbon compounds ethylene glycol and glycolate.


    Pereira, Brian; Li, Zheng-Jun; De Mey, Marjan; Lim, Chin Giaw; Zhang, Haoran; Hoeltgen, Claude; Stephanopoulos, Gregory


    The development of lignocellulose as a sustainable resource for the production of fuels and chemicals will rely on technology capable of converting the raw materials into useful compounds; some such transformations can be achieved by biological processes employing engineered microorganisms. Towards the goal of valorizing the hemicellulose fraction of lignocellulose, we designed and validated a set of pathways that enable efficient utilization of pentoses for the biosynthesis of notable two-carbon products. These pathways were incorporated into Escherichia coli, and engineered strains produced ethylene glycol from various pentoses, including simultaneously from D-xylose and L-arabinose; one strain achieved the greatest reported titer of ethylene glycol, 40 g/L, from D-xylose at a yield of 0.35 g/g. The strategy was then extended to another compound, glycolate. Using D-xylose as the substrate, an engineered strain produced 40 g/L glycolate at a yield of 0.63 g/g, which is the greatest reported yield to date. PMID:26711083

  8. 76 FR 31471 - Ethylene Glycol; Exemption From the Requirement of a Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014


    ... ethylene glycol. In the Federal Register of July 9, 2008 (73 FR 39291) (FRL-8371-2), EPA issued a notice... comment in response to the notice of filing. Also, in the Federal Register of August 4, 2004 (69 FR 47149... Order 12866, entitled Regulatory Planning and Review (58 FR 51735, October 4, 1993). Because this...

  9. Insights on cryoprotectant toxicity from gene expression profiling of endothelial cells exposed to ethylene glycol.


    Cordeiro, Rui Martins; Stirling, Soren; Fahy, Gregory M; de Magalhães, João Pedro


    Cryopreservation consists of preserving living cells or tissues generally at -80 °C or below and has many current applications in cell and tissue banking, and future potential for organ banking. Cryoprotective agents such as ethylene glycol (EG) are required for successful cryopreservation of most living systems, but have toxic side effects whose mechanisms remain largely unknown. In this work, we investigated the mechanisms of toxicity of ethylene glycol in human umbilical vein endothelial cells (HUVECs) as a model of the vascular endothelium in perfused organs. Exposing cells to 60% v/v EG for 2 h at 4 °C resulted in only a slight decrease in subsequent cell growth, suggesting only modest toxicity of EG for this cell type. Gene expression analysis with whole genome microarrays revealed signatures indicative of a generalized stress response at 24 h after EG exposure and a trend toward partial recovery at 72 h. The observed changes involved signalling pathways, glycoproteins, and genes involved in extracellular and transmembrane functions, the latter suggesting potential effects of ethylene glycol on membranes. These results continue to develop a new paradigm for understanding cryoprotectant toxicity and reveal molecular signatures helpful for future experiments in more completely elucidating the toxic effects of ethylene glycol in vascular endothelial cells and other cell types. PMID:26471925


    EPA Science Inventory


    The position paper, An Evaluation of the Human Carcinogenic Potential of Ethylene Glycol Butyl Ether, was developed in support of the Agency's evaluation of a petition from the...

  11. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (EGBE) (Interagency Science Discussion Draft)

    EPA Science Inventory

    EPA is releasing the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessme...


    EPA Science Inventory

    Subacute (10-day) and subchronic (90-day) toxicity studies of ethylene glycol (EG) were conducted in male and female sprague-Dawley rats to provide the U.S. Environmental Protection Agency's (EPA) Office of Drinking Water with toxicity data for final preparation of a Health Advis...

  13. One step synthesis of C-dots by microwave mediated caramelization of poly(ethylene glycol).


    Jaiswal, Amit; Ghosh, Siddhartha Sankar; Chattopadhyay, Arun


    A rapid, simple and one step microwave mediated method for synthesizing C-dots using poly(ethylene glycol) (PEG) as a precursor and passivating agent is reported. The C-dots possessed low cytotoxicity, were amenable to separation by electrophoresis, photostable and entered cancer cells, making them suitable candidates for bioimaging and biolabelling. PMID:22075768

  14. The Effect of Ethylene Glycol, Glycine Betaine, and Urea on Lysozyme Thermal Stability

    ERIC Educational Resources Information Center

    Schwinefus, Jeffrey J.; Leslie, Elizabeth J.; Nordstrom, Anna R.


    The four-week student project described in this article is an extension of protein thermal denaturation experiments to include effects of added cosolutes ethylene glycol, glycine betaine, and urea on the unfolding of lysozyme. The transition temperatures and van't Hoff enthalpies for unfolding are evaluated for six concentrations of each cosolute,…

  15. Spectrophotometric technique quantitatively determines NaMBT inhibitor in ethylene glycol-water solutions

    NASA Technical Reports Server (NTRS)

    Garrard, G. G.


    Spectrophotometric method, using a ratio-recording ultraviolet-absorption spectrophotometer, permits analysis of NaMBT in ethylene glycol-water solutions with high accuracy. It reduces analysis time, requires smaller samples, and is able to detect extremely small concentrations of mercaptobenzothiazole.

  16. Reaction Kinetics of Ethylene Glycol Reforming over Platinum in the Vapor versus Aqueous Phases

    SciTech Connect

    Kandoi, Shampa; Greeley, Jeffrey P.; Simonetti, Dante A.; Shabaker, John; Dumesic, James A.; Mavrikakis, Manos


    First-principles, periodic, density functional theory (DFT) calculations are carried out on Pt(111) to investigate the structure and energetics of dehydrogenated ethylene glycol species and transition states for the cleavage of C-H/O-H and C-C bonds. Additionally, reaction kinetics studies are carried out for the vapor phase reforming of ethylene glycol (C2H6O2) over Pt/Al2O3 at various temperatures, pressures, and feed concentrations. These results are compared to data for aqueous phase reforming of ethylene glycol on this Pt catalyst, as reported in a previous publication (Shabaker, J. W.; et al. J. Catal. 2003, 215, 344). Microkinetic models were developed to describe the reaction kinetics data obtained for both the vapor-phase and aqueous-phase reforming processes. The results suggest that C-C bond scission in ethylene glycol occurs at an intermediate value of x (3 or 4) in C2HxO2. It is also found that similar values of kinetic parameters can be used to describe the vapor and aqueous phase reforming data, suggesting that the vapor phase chemistry of this reaction over platinum is similar to that in the aqueous phase over platinum.

  17. Reaction kinetics of ethylene glycol reforming over platinum in the vapor versus aqueous phases

    SciTech Connect

    Kandoi, Shampa; Greeley, Jeff; Simonetti, Dante; Shabaker, John; Dumesic, James A.; Mavrikakis, Manos


    First-principles, periodic, density functional theory (DFT) calculations are carried out on Pt(111) to investigate the structure and energetics of dehydrogenated ethylene glycol species and transition states for the cleavage of C–H/O–H and C–C bonds. Additionally, reaction kinetics studies are carried out for the vapor phase reforming of ethylene glycol (C₂H₆O₂) over Pt/Al₂O₃ at various temperatures, pressures, and feed concentrations. These results are compared to data for aqueous phase reforming of ethylene glycol on this Pt catalyst, as reported in a previous publication (Shabaker, J. W.; et al. J. Catal. 2003, 215, 344). Microkinetic models were developed to describe the reaction kinetics data obtained for both the vapor-phase and aqueous-phase reforming processes. The results suggest that C–C bond scission in ethylene glycol occurs at an intermediate value of x (3 or 4) in C₂HxO₂. It is also found that similar values of kinetic parameters can be used to describe the vapor and aqueous phase reforming data, suggesting that the vapor phase chemistry of this reaction over platinum is similar to that in the aqueous phase over platinum.


    EPA Science Inventory

    Microwave-assisted (MW), surfactantless, greener approach to bulk synthesis of silver nanorods employing poly (ethylene glycol) (PEG) is described. An aqueous solution of silver nitrate (AgNO-3,- 0.1 M, 4 mL) and 4 mL of PEG (molecular weight 300) were mixed at room temperature t...

  19. Importance of poly(ethylene glycol) conformation for the synthesis of silver nanoparticles in aqueous solution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the formation of silver nanoparticles (NPs) using silver nitrate in a poly(ethylene glycol) (PEG) aqueous solution, which acts as both a reducing and stabilizing agent, the PEG chain structure was found to play a significant role. Even though PEG 100 (100 kg/mol) has limited reducing sites of hyd...

  20. Human Oocyte Vitrification: The permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

    PubMed Central

    Mullen, Steven F.; Li, Mei; Li, Yuan; Chen, Zi-Jiang; Critser, John K.


    Objectives To determine the permeability of human metaphase II oocytes to ethylene glycol and water in the presence of ethylene glycol, and to use this information to develop a method to vitrify human oocytes. Design An incomplete randomized block design was used for this study. Setting A University-affiliated assisted reproductive center. Patients Women undergoing assisted reproduction in the Center for Reproductive Medicine at Shandong University. Interventions Oocytes were exposed to 1.0 molar ethylene glycol in a single step, and photographed during subsequent volume excursions. Main outcome measures A 2-parameter model was employed to estimate the permeability to water and EG. Results Water permeability ranged from 0.15 to 1.17 µm/(min·atm), and ethylene glycol permeability ranged from 1.5 to 30 µm/min between 7 °C at 36 °C. The activation energies for water and ethylene glycol permeability were 14.42 Kcal/mol and 21.20 Kcal/mol, respectively. Conclusions Despite the lower permeability of human MII oocytes to ethylene glycol compared to previously published values for propylene glycol and dimethylsulfoxide, methods to add and remove human oocytes with a vitrifiable concentration of ethylene glycol can be designed which prevent excessive osmotic stress and minimize exposure to high concentrations of this compound. PMID:17681308

  1. Thermosensitivity of bile acid-based oligo(ethylene glycol) stars in aqueous solutions.


    Strandman, Satu; Le Dévédec, Frantz; Zhu, X X


    Amphiphilic star-shaped oligo(ethylene glycol)s with a hydrophobic bile acid core and varying number of hydrophilic arms have been made. Their thermal behavior in aqueous solutions depends on the number rather than the length of the arms. The two-armed lithocholate derivative showed the strongest tendency for association and exhibited the lowest cloud point (79 °C) of the oligomers made, as well as another phase separation at a lower temperature (31 °C). The "double thermosensitivity" arising both from the salt-dependent LCST of the oligo(ethylene glycol) segments and the temperature-responsive self-assembly of amphiphilic bile acid derivative provides an interesting path in the design of bile acid-based smart materials. PMID:21661073

  2. [Heat resistance of "Bacillus subtilis" and "Bacillus stearothermophilus" spores in ethylene glycol, propylene glycol and butylene glycol solutions. Criticism of the use of thermodynamic parameters (author's transl)].


    Cerf, O; L'Haridon, R; Hermier, J


    Increasing concentrations of ethylene glycol (EG), 1,2-propylene glycol (PG) or 2,3-butylene glycol (BG) lower the heat resistance of B. subtilis SJ2 and B. stearothermophilus 1518 spores, and there is a linear relationship between logarithm of decimal reduction time (D) and glycol concentration. D120 degreesc values of B. subtilis spores in 0.02M, pH 7.0 phosphate buffer containing 20 per cent (w/w) EG, PG and BG are respectively 1, 0.7 and 1.1 min compared to 1.5 min in buffer alone. Corresponding values for B. stearothermophilus spores are 2, 2.4 and 3 min compared to 3.2 min. The type of glycol has little effect upon temperature coefficient z for destruction of the B. subtilis spores (average 6.9 degrees C). On the contrary, in the case of B. stearothermophilus, z increases when the number of carbons increases in the glycol molecule (from 7 to 15 degrees). The thermodynamic parameters which characterize the activation of the spore destruction reaction cannot lead to a general conclusion about a possible mechanism of destruction in the presence of chemical compounds belonging to an homologous series: the two behave diversely, and there is no "isokinetic temperature". PMID:811145

  3. Effect of Short Chain Poly(ethylene glycol)s on the Hydration Structure and Dynamics around Human Serum Albumin.


    Samanta, Nirnay; Luong, Trung Quan; Das Mahanta, Debasish; Mitra, Rajib Kumar; Havenith, Martina


    We report the changes in the hydration dynamics around a globular protein, human serum albumin (HSA), in the presence of two short chain crowding agents, namely poly(ethylene glycol)s (PEG 200 and 400). The change in the network water structure is investigated using FTIR spectroscopy in the far-infrared (FIR) frequency range. Site specific changes are obtained by time-resolved fluorescence spectroscopic technique using the intrinsic fluorophore tryptophan (Trp214) of HSA. The collective hydration dynamics of HSA in the presence of PEG molecules are obtained using terahertz (THz) time domain spectroscopy (TTDS) and high intensity p-Ge THz measurements. Our study affirms a considerable perturbation of HSA hydration beyond a critical concentration of PEG. PMID:26720549

  4. Ultrasound responsive block copolymer micelle of poly(ethylene glycol)-poly(propylene glycol) obtained through click reaction.


    Li, Fayong; Xie, Chuan; Cheng, Zhengang; Xia, Hesheng


    The well-defined amphiphilic poly(ethylene glycol)-block-poly(propylene glycol) copolymer containing 1, 2, 3-triazole moiety and multiple ester bonds (PEG-click-PPG) was prepared by click reaction strategy. The PEG-click-PPG copolymer can self-assemble into spherical micelles in aqueous solution. It is found that high intensity focused ultrasound (HIFU) can open the copolymer PEG-click-PPG micelles and trigger the release of the payload in the micelle. The multiple ester bonds introduced in the junction point of the copolymer chain through click reactions were cleaved under HIFU, and leads to the disruption of the copolymer micelle and fast release of loaded cargo. The click reaction provides a convenient way to construct ultrasound responsive copolymer micelles with weak bonds. PMID:26703197

  5. Ethylene glycol (antifreeze) poisoning in a free-ranging polar bear

    SciTech Connect

    Amstrup, S.C.; Gardner, C.; Myers, K.C.; Oehme, F.W. )


    The bright, fluorescent pink-colored remains of a polar bear were found on an Alaskan island with the gravel and snow adjacent to the bear colored bright purple. Traces of fox urine and feces found nearby were also pink. The pink and purple colors were due to rhodamine B, and ethylene glycol (EG) was present in the soil under the carcass. Evidence is given to suggest the bear consumed a mixture of rhodamine B and EG commonly used to mark roads and runways during snow and ice periods. Such wildlife losses could be prevented by substituting propylene glycol for the EG in such mixtures.

  6. Miscibility and degradability of poly(lactic acid)poly(ethylene oxide)/poly(ethylene glycol) blends

    SciTech Connect

    Yue, C.L.; Dave, V.; Gross, R.A.; McCarthy, S.P.


    Poly(lactic acid) [PLA] was melt blended with polyethylene(oxide) [PEG] and poly(ethylene glycol) [PEG] in different compositions to form blown films. It was determined that PLA was miscible with PEO in all compositions. Based on Gordon-Taylor equation, it was determined that the interactions between PLA and PEO is stronger than PEG. The addition of low molecular weight PEG improved the elongation and tear strength of the blends. Enzymatic degradation results shows that the weight loss of all the samples was more than 80% of the initial weight in 48 hours.

  7. Poly(ethylene glycol) grafted chitosan as new copolymer material for oral delivery of insulin

    NASA Astrophysics Data System (ADS)

    Ho, Thanh Ha; Thanh Le, Thi Nu; Nguyen, Tuan Anh; Chien Dang, Mau


    A new scheme of grafting poly (ethylene glycol) onto chitosan was proposed in this study to give new material for delivery of insulin over oral pathway. First, methoxy poly(ethylene glycol) amine (mPEGa MW 2000) were grafted onto chitosan (CS) through multiples steps to synthesize the grafting copolymer PEG-g-CS. After each synthesis step, chitosan and its derivatives were characterized by FTIR, 1H NMR Then, insulin loaded PEG-g-CS nanoparticles were prepared by cross-linking of CS with sodium tripolyphosphate (TPP). Same insulin loaded nanoparticles using unmodified chitosan were also prepared in order to compare with the modified ones. Results showed better protecting capacity of the synthesized copolymer over original CS. CS nanoparticles (10 nm of size) were gel like and high sensible to temperature as well as acidic environment while PEG-g-CS nanoparticles (200 nm of size) were rigid and more thermo and pH stable.

  8. Methoxy poly(ethylene glycol) conjugated doxorubicin micelles for effective killing of cancer cells.


    Zhang, Liming; Xia, Kai; Deng, Yan; Li, Song; Zhang, Chuanxiang; Lu, Zhuoxuan; He, Nongyue


    Methoxy poly(ethylene glycol) conjugated doxorubicin (mPEG-DOX) micelles are prepared for delivering drug effectively. The core of the unimolecular micelle is a DOX (doxorubicin) which is an anti-cancer chemotherapy drug, while the outer hydrophilic shell is composed of poly(ethylene glycol) (PEG) segments. Dynamic light scattering (DLS) analysis shows that the unimolecular micelles are uniform with a mean hydrodynamic diameter around 250 nm. The mPEG-DOX micelles can be internalized by the cancer cells and exhibit good cell uptake by the fluorescence microscopy. Obvious cytotoxicity is also observed when the concentration (count on DOX) is over 1 μg/mL. These findings indicate that these unique unimolecular micelles may offer a very promising approach for targeted cancer therapy. PMID:25936136

  9. Ethylene glycol and the thermostability of trypsin in a reverse micelle system.


    Stupishina, E A; Khamidullin, R N; Vylegzhanina, N N; Faizullin, D A; Zuev, Yu F


    The influence of ethylene glycol (EG) on the kinetics of hydrolysis of N-alpha-benzoyl-L-arginine ethyl ether catalyzed by trypsin encapsulated in sodium bis-(2-ethylhexyl)sulfosuccinate (AOT)-based reverse micelles was studied at different temperatures. Ethylene glycol was shown to shift the range of the trypsin activity in the reverse micelles towards higher temperatures. Infrared spectroscopy showed a stabilizing effect of EG on the secondary structure of the protein in the system of reverse micelles. Electron spin resonance spectroscopy showed that the solubilized protein affected the interactions of EG with the polar head groups of AOT and altered the rigidity of the micellar matrix. The results indicate that EG increases the thermostability of the solubilized enzyme in microemulsion media by two mechanisms. PMID:16732732

  10. Fate of ethylene glycol in the environment. Final report, 1987-1989

    SciTech Connect

    Abdelghani, A.A.; Anderson, A.C.; Khoury, G.A.; Chang, S.N.


    The Louisiana Department of Transportation and Development uses ethylene glycol (EG) as a deicing agent on bridges. The study was undertaken to assess the impact of ethylene glycol on workers and the environment after spraying. The objectives of the project were to determine the level of exposure of workers spraying EG on bridges; to monitor the level of EG in the atmosphere above sprayed bridges; to determine the aqueous concentrations of EG due to runoff of the chemical from sprayed bridges to the aquatic environment; and to determine the effect of EG in the aquatic environment including sorption capacity to soil, acute toxicity to bluegill sunfish, crawfish, and microorganisms, bioaccumulation in crawfish, and biodegradation by soil microorganisms.

  11. Antilithiatic effect of Asparagus racemosus Willd on ethylene glycol-induced lithiasis in male albino Wistar rats.


    Christina, A J M; Ashok, K; Packialakshmi, M; Tobin, G C; Preethi, J; Murugesh, N


    The ethanolic extract of Asparagus racemosus Willd. was evaluated for its inhibitory potential on lithiasis (stone formation), induced by oral administration of 0.75% ethylene glycolated water to adult male albino Wistar rats for 28 days. The ionic chemistry of urine was altered by ethylene glycol, which elevated the urinary concentration of crucial ions viz. calcium, oxalate, and phosphate, thereby contributing to renal stone formation. The ethanolic extract, however, significantly (p < 0.05) reduced the elevated level of these ions in urine. Also, it elevated the urinary concentration of magnesium, which is considered as one of the inhibitors of crystallization. The high serum creatinine level observed in ethylene glycol-treated rats was also reduced, following treatment with the extract. The histopathological findings also showed signs of improvement after treatment with the extract. All these observations provided the basis for the conclusion that this plant extract inhibits stone formation induced by ethylene glycol treatment. PMID:16357948

  12. Acrosomal ultrastructure of stallion spermatozoa cryopreserved with ethylene glycol using two packaging systems.


    Alvarenga, M A; Landim-Alvarenga, F C; Moreira, R M; Cesarino, M M


    The present experiments aimed to examine the substitution of glycerol (G) by ethylene glycol (E) as a cryoprotective agent for stallion spermatozoa. Two different ethylene glycol concentrations (5% and 10%) and also the association of glycerol (2%) and ethylene glycol (3%) (E/G) were studied (Experiment 1). In Experiment 2, two packing systems (0.5 x 4.0 ml) were evaluated using both cryoprotectors. In both experiments, the sperm membrane integrity after freezing was evaluated using transmission electron microscopy. The mean post-thaw motility was 34.25, 36.5, 29.25 and 34.75% for G5%, E5%, E10% and E/G, respectively. It was observed that the percentage of motile spermatozoa was significantly smaller (P<0.05) when semen was processed with E10%. A decrease in the acrosome integrity was observed in frozen thawed spermatozoa from all treated groups. It was observed that 28.0, 22.5, 25.5 and 22.5% of the sperm cells had a normal acrosome following freezing with G5%, E5%, E10% and E/G, respectively. Undulation of the outer acrosomal membrane, acrosomal swelling and loss of acrosomal content density and homogeneity were the most evident ultrastructural alterations observed. In Experiment 2, the post-thaw motility was higher (P<0.05) for sperm frozen in 0.5 ml straws than in 4.0 ml straws, regardless of the cryoprotector used. The ultrastructural evaluation showed 26.7 and 16.0% of intact acrosomes for sperm frozen in 0.5 ml and 4.0 ml straws, respectively. We concluded that ethylene glycol has similar cryoprotective properties to glycerol and that utilisation of 0.5 ml straws improved the ability of horse sperm cells to withstand damage after the cryopreservation process. PMID:11093629

  13. Dendritic polyglycerol-poly(ethylene glycol)-based polymer networks for biosensing application.


    Dey, Pradip; Adamovski, Miriam; Friebe, Simon; Badalyan, Artavazd; Mutihac, Radu-Cristian; Paulus, Florian; Leimkühler, Silke; Wollenberger, Ulla; Haag, Rainer


    This work describes the formation of a new dendritic polyglycerol-poly(ethylene glycol)-based 3D polymer network as a matrix for immobilization of the redox enzyme periplasmatic aldehyde oxidoreductase to create an electrochemical biosensor. The novel network is built directly on the gold surface, where it simultaneously stabilizes the enzyme for up to 4 days. The prepared biosensors can be used for amperometric detection of benzaldehyde in the range of 0.8-400 μM. PMID:24882361

  14. Thermal performance of ethylene glycol based nanofluids in an electronic heat sink.


    Selvakumar, P; Suresh, S


    Heat transfer in electronic devices such as micro processors and power converters is much essential to keep these devices cool for the better functioning of the systems. Air cooled heat sinks are not able to remove the high heat flux produced by the today's electronic components. Liquids work better than air in removing heat. Thermal conductivity which is the most essential property of any heat transfer fluid can be enhanced by adding nano scale solid particles which possess higher thermal conductivity than the liquids. In this work the convective heat transfer and pressure drop characteristics of the water/ethylene glycol mixture based nanofluids consisting of Al2O3, CuO nanoparticles with a volume concentration of 0.1% are studied experimentally in a rectangular channel heat sink. The nano particles are characterized using Scanning Electron Microscope and the nannofluids are prepared by using an ultrasonic vibrator and Sodium Lauryl Salt surfactant. The experimental results showed that nanofluids of 0.1% volume concentration give higher convective heat transfer coefficient values than the plain water/ethylene glycol mixture which is prepared in the volume ratio of 70:30. There is no much penalty in the pressure drop values due to the inclusion of nano particles in the water/ethylene glycol mixture. PMID:24745228

  15. Electrochemical synthesis of poly(3-aminophenylboronic acid) in ethylene glycol without exogenous protons.


    Wang, Feifan; Zou, Feixue; Yu, Xinxin; Feng, Zhenyu; Du, Na; Zhong, Yaohua; Huang, Xirong


    A non-aqueous solution of tetra-n-butylammonium fluoride (TBAF) in ethylene glycol has been tried for the first time as a supporting electrolyte for the electropolymerization of 3-aminophenylboronic acid (APBA). Unlike the traditional acidic aqueous solution, the present medium needs no exogenous protons; moreover, the presence of CF3COOH is found to be unfavorable for the polymerization. The protons are in situ generated by the reaction between the boronic acid group on APBA and 1,2-dihydroxyl on ethylene glycol. So, ethylene glycol serves as not only the solvent but also the proton source. As a part of the supporting electrolyte, F(-) is found to be involved in the electrochemical synthesis of poly(3-aminophenylboronic acid) (PAPBA), but it is not indispensable. Studies on the electropolymerization process indicate that the size of the ions in the electrolyte affects the rate of the doping/dedoping process. The smaller the cation, the easier the doping/dedoping process, and the better the stability of the grown film. As demonstrated by Fourier transform infrared spectra, UV-vis spectra, and scanning electron microscopy, the obtained PAPBA is a cross-linked nanoporous polymer membrane that has a good adherence to the glassy carbon electrode. PMID:27004602

  16. Relative toxicities of pure propylene and ethylene glycol and formulated deicers on plant species

    SciTech Connect

    DuFresne, D.L.; Pillard, D.A.


    Propylene and ethylene glycol deicers are commonly used at airports in the US and other countries to remove and retard the accumulation of snow and ice on aircraft. Deicers may not only enter water bodies without treatment, due to excessive storm-related flow, but also may expose terrestrial organisms to high concentrations through surface runoff. Most available toxicity data are for aquatic vertebrates and invertebrate species; this study examined effects on terrestrial and aquatic plants. Terrestrial plant species included both a monocot (rye grass, Lolium perenne) and a dicot (lettuce, Lactuca saliva). Aquatic species included a single cell alga (Selenastrum capricomutum), and an aquatic macrophyte (duckweed, Lemna minor). Glycol deicers were obtained in the formulated mixtures used on aircraft. Pure ethylene and propylene glycol were obtained from Sigma{reg_sign}. Parameters measured included germination, root and shoot length, survival, and growth. Formulated deicers, like those used at airports, were generally more toxic than pure chemicals, based on glycol concentration. This greater toxicity of formulated deicers is consistent with results of tests using animal species.

  17. Evaluation of glove material resistance to ethylene glycol dimethyl ether permeation

    SciTech Connect

    Menke, R.; Chelton, C.F.


    Some glycol ethers have been reported to cause adverse reproductive effects in exposed male and female workers, and skin absorption has been determined to be an important route of entry of this class of chemicals. Because ethylene glycol dimethyl ether (EGDME) is a possible component of lithium-based primary battery electrolyte systems, a study was undertaken to determine the resistance of various commercially available gloves to permeation of this liquid. The gloves were tested by the ASTM Method F-739-81, and butyl rubber was found to be the most effective barrier to permeation. Further studies determined that the butyl gloves could be reused if they were reconditioned overnight in a vacuum oven at 50 degrees C. When a mixture of ethylene glycol dimethyl ether (30% v/v) and propylene carbonate (70% v/v) was tested, the results indicated that the propylene carbonate retards the permeation of the glycol ether by a factor of 10. This is believed to be caused by the propylene carbonate coating the surface of the butyl membrane to reduce the sorption of EGDME.

  18. Evaluation of glove material resistance to ethylene glycol dimethyl ether permeation.


    Menke, R; Chelton, C F


    Some glycol ethers have been reported to cause adverse reproductive effects in exposed male and female workers, and skin absorption has been determined to be an important route of entry of this class of chemicals. Because ethylene glycol dimethyl ether (EGDME) is a possible component of lithium-based primary battery electrolyte systems, a study was undertaken to determine the resistance of various commercially available gloves to permeation of this liquid. The gloves were tested by the ASTM Method F-739-81, and butyl rubber was found to be the most effective barrier to permeation. Further studies determined that the butyl gloves could be reused if they were reconditioned overnight in a vacuum oven at 50 degrees C. When a mixture of ethylene glycol dimethyl ether (30% v/v) and propylene carbonate (70% v/v) was tested, the results indicated that the propylene carbonate retards the permeation of the glycol ether by a factor of 10. This is believed to be caused by the propylene carbonate coating the surface of the butyl membrane to reduce the sorption of EGDME. PMID:3177216

  19. Aqueous sols of oligo(ethylene glycol) surface decorated polydiacetylene vesicles for colorimetric detection of Pb 2+.


    Narkwiboonwong, Pat; Tumcharern, Gamolwan; Potisatityuenyong, Anupat; Wacharasindhu, Sumrit; Sukwattanasinitt, Mongkol


    A series of ethylene glycol (EG), triethylene glycol (3EG) and pentaethylene glycol (5EG) esters of 10,12-pentacosadiynoic acid (PCDA) are synthesized. The glycol ester lipids can be hydrated and well dispersed in water but they cannot form polydiacetylenes upon UV irradiation. They however can be mixed with PCDA up to 30 mol% and polymerized to form blue sols. The mixed polydiacetylene sols show blue to red thermochromic transition with two-stepped transition temperatures. The first transition temperature decreases with the increase of the glycol ester content as well as the length of their chains indicating greater fluidity of the self-assembled structure due to less collaborative hydrogen bonding among the lipid head groups. These mixed polydiacetylene sol prepared from 30 mol% of the penta(ethylene glycol) ester show linear colorimetric response selectively to Pb(2+) in the range of 5-30 μM. PMID:21147331

  20. Comparative toxicity of formulated glycol deicers and pure ethylene and propylene glycol to Ceriodaphnia dubia and Pimephales promelas

    SciTech Connect

    Pillard, D.A. )


    Airlines use deicers to remove ice and snow from aircraft before flights, and to retard the inflight buildup of these materials. Many of the deicers are formulated mixtures of ethylene glycol (EG) or propylene glycol (PG) and a variety of additives. Because these deicers may be intentionally or accidentally released into aquatic ecosystems, the possibility exists for direct and indirect adverse effects on aquatic organisms. Laboratory studies evaluated the comparative toxicity of formulated glycol deicers and pure materials on the water flea, Ceriodaphnia dubia, and fathead minnow, Pimephales promelas. Acute and short-term chronic tests were performed according to US Environmental Protection Agency (EPA) guidelines. The formulated mixtures were found to be substantially more toxic than either of the pure glycol materials. The 48-h LC50s for C. dubia were 13,140 mg/L and 1,020 mg/L using formulated EG and PG, and 34,400 mg/L and 18,340 mg/L using pure EG and PG, respectively. The 96-h LC50s for P. promelas were 8,050 mg/L and 710 mg/L using formulated EG and PG, and 72,860 mg/L and 55,770 mg/L using pure EG and PG, respectively. Chronic IC25s for C. dubia were 3,960 mg/L and 640 mg/L using formulated EG and PG; 12,310 mg/L and 13,470 mg/L using pure EG and PG. Chronic IC25s for P. promelas were 3,660 mg/L and 110 mg/L using formulated EG and PG; 22,520 mg/L and 6,940 mg/L using pure EG and PG. For airports that have stormwater discharge permits, numerical limits for EG and PG are generally listed; potential toxicity is assumed to be due to the glycol materials. However, other compounds in the mixtures may either contribute substantially to, or in some cases overshadow, the toxicity of the glycol materials.

  1. Dexamethasone-loaded poly(D, L-lactic acid) microspheres/poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) micelles composite for skin augmentation.


    Fan, Min; Liao, Jinfeng; Guo, Gang; Ding, Qiuxia; Yang, Yi; Luo, Feng; Qian, Zhiyong


    Soft tissue augmentation using various injectable fillers has gained popularity as more patients seek esthetic improvement through minimally invasive procedures requiring little or no recovery time. The currently available injectable skin fillers can be divided into three categories. With careful assessment, stimulatory fillers are the most ideal fillers. In this study, dexamethasone-loaded poly(D, L-lactic acid) (PLA) microspheres of approximately 90 micro m suspended in poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) micelles were prepared as stimulatory filler for skin augmentation. The biodegradable PECE copolymer can form nano-sized micelles in water, which instantly turns into a non-flowing gel at body temperature due to micellar aggregation. The PECE micelles (making up 90% of composite) served as vehicle for subcutaneous injection were metabolized within 44 days. At the same time, the dexamethasone-loaded PLA microspheres (10% of composite) merely served as stimulus for connective tissue formation. Dexamethasone-loaded PLA microspheres/PECE micelles composite presented great hemocompatibility in vitro. It was demonstrated in the in vive study that the composite was biodegradable, biocompatible, nontoxic and nonmigratory. Histopathological studies indicated that the composite could stimulate collagen regeneration. Furthermore, granuloma, the main complication of the stimulatory fillers, did not appear when the composite was injected into the back of SD rats, because of the dexamethasone controlled release from the composite. All results suggested that dexamethasone-loaded PLA microspheres/PECE micelles composite may be an efficient and promising biomaterial for skin augmentation. PMID:24734511

  2. Toxicities of ethylene glycol and ethylene glycol monoethyl ether in Fischer 344/N rats and B6C3F1 mice.

    PubMed Central

    Melnick, R L


    The toxicities of ethylene glycol (EG) and ethylene glycol monoethyl ether (EGEE) were studied in Fischer 344/N rats and B6C3F1 mice. In a 13-week study, EG was administered in feed to groups of 10 rats and 10 mice of both sexes at dose levels of 0 (control), 0.32, 0.63, 1.25, 2.5 and 5.0%. Kidney/body weight ratios were elevated in the 2.5 and 5.0% dose groups of male and female rats relative to controls, while serum urea nitrogen and serum creatinine levels were elevated in the two highest dose groups of male rats. Toxic nephrosis and crystal deposits in renal tubules were observed in the 2.5 and 5.0% dose groups of male rats. Crystals were also observed in brains of male rats in the 5.0% dose group. Nephrosis was the only lesion observed in female rats (5.0% dose group). Mild, compound-related lesions were seen in kidneys (nephrosis) and livers (centrilobular degeneration) of male mice in the 2.5 and 5.0% dose groups. There were no adverse effects observed in female mice. Groups of 50 rats and 50 mice of both sexes were administered EGEE by gavage in a 2-year study at dose levels of 0 (control), 0.5, 1.0 and 2.0 g/kg body weight. Testicular atrophy was observed in male rats that died early in this study and in the medium- and high-dose male mouse groups.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6499799

  3. Poly(ethylene glycol)-poly(lactic-co-glycolic acid) based thermosensitive injectable hydrogels for biomedical applications.


    Alexander, Amit; Ajazuddin; Khan, Junaid; Saraf, Swarnlata; Saraf, Shailendra


    Stimuli triggered polymers provide a variety of applications related with the biomedical fields. Among various stimuli triggered mechanisms, thermoresponsive mechanisms have been extensively investigated, as they are relatively more convenient and effective stimuli for biomedical applications. In a contemporary approach for achieving the sustained action of proteins, peptides and bioactives, injectable depots and implants have always remained the thrust areas of research. In the same series, Poloxamer based thermogelling copolymers have their own limitations regarding biodegradability. Thus, there is a need to have an alternative biomaterial for the formulation of injectable hydrogel, which must remain biocompatible along with safety and efficacy. In the same context, poly(ethylene glycol) (PEG) based copolymers play a crucial role as a biomedical material for biomedical applications, because of their biocompatibility, biodegradability, thermosensitivity and easy controlled characters. This review stresses on the physicochemical property, stability and composition prospects of smart PEG/poly(lactic-co-glycolic acid) (PLGA) based thermoresponsive injectable hydrogels, recently utilized for biomedical applications. The manuscript also highlights the synthesis scheme and stability characteristics of these copolymers, which will surely help the researchers working in the same area. We have also emphasized the applied use of these smart copolymers along with their formulation problems, which could help in understanding the possible modifications related with these, to overcome their inherent associated limitations. PMID:24144918

  4. Effects of hydrophobic drug polyesteric core interactions on drug loading and release properties of poly(ethylene glycol) polyester poly(ethylene glycol) triblock core shell nanoparticles

    NASA Astrophysics Data System (ADS)

    Khoee, Sepideh; Hassanzadeh, Salman; Goliaie, Bahram


    BAB amphiphilic triblock copolymers consisting of poly(ethylene glycol) (B) (PEG) as the hydrophilic segment and different polyesters (A) as the hydrophobic block were prepared by a polycondensation reaction as efficient model core-shell nanoparticles to assay the effect of interactions between the hydrophobic drug and the polyesteric core in terms of drug loading content and release profile. PEG-poly(hexylene adipate)-PEG (PEG-PHA-PEG) and PEG-poly(butylene adipate)-PEG (PEG-PBA-PEG) to PEG-poly(ethylene adipate)-PEG (PEG-PEA-PEG) core-shell type nanoparticles entrapping quercetin (an anticarcinogenic, allergy inhibitor and antibacterial agent), were prepared by a nanoprecipitation method and characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM) and x-ray diffraction (XRD) techniques. It was found that the obtained nanoparticles showed a smooth surface and spherical shape with controllable sizes in the range of 64-74 nm, while drug loading varied from 7.24% to 19% depending on the copolymer composition and the preparation conditions. The in vitro release behaviour exhibited a sustained release and was affected by the polymer-drug interactions. UV studies revealed the presence of hydrogen bonding as the main existing interaction between quercetin and polyesters in the nanosphere cores.


    SciTech Connect

    Corley, Rick A.; Bartels, M J.; Carney, E W.; Weitz, Karl K.; Soelberg, Jolen J.; Gies, Richard A.; Thrall, Karla D.


    An extensive database on the toxicity and modes of action of the major industrial chemical, ethylene glycol (EG), has been developed over the past several decades. These studies have consistently identified the kidney as a primary target organ, with rats being more sensitive than mice and males more sensitive than females following chronic exposure. Renal toxicity has been associated with the terminal metabolite, oxalic acid which can precipitate with calcium to form crystals. EG also induces developmental toxicity, although these effects appear to require high-doses or accelerated dose-rates, and have been reported only in rats and mice. The developmental toxicity of EG has been attributed to the intermediate metabolite, glycolic acid (GA). The developmental toxicity of EG has been the subject of extensive research and regulatory review in recent years. Therefore, a physiologically based pharmacokinetic (PBPK) model was developed to integrate the extensive mode of action and pharmacokinetic data on EG and GA for use in developmental risk assessment. Metabolic rate constants and partition coefficients for EG and GA were estimated from in vitro studies. Other biochemical constants were optimized from appropriate in vivo pharmacokinetic studies. The resulting PBPK model includes inhalation, oral, dermal, intravenous and subcutaneous routes of administration. Metabolism of EG and GA were described in the liver with elimination via the kidneys. Several rat and human metabolism studies were used to validate the resulting PBPK model. Consistent with these studies, simulations indicated that the metabolism of EG to GA was essentially first-order (linear) up to 2500 mg/kg/day while the metabolism of GA saturated between bolus ethylene glycol doses of 200 and 1000 mg/kg/day. This saturation results in non-linear increases in blood GA concentrations, correlating with the developmental toxicity of EG. Pregnancy had no effect on maternal EG and GA kinetics over a broad dose

  6. A cross-sectional study of ethylene glycol monomethyl ether process employees

    SciTech Connect

    Cook, R.R.; Bodner, K.M.; Kolesar R.C.; Uhlmann, C.S.; Van Peenen, P.F.D.; Dickson, D.S.; Flanagan, K.


    Human exposures to ethylene glycol monomethyl ether have been associated with hematological and neurological abnormalities. Recent animal toxicology studies have also reported testicular atrophy. To determine whether employees potentially exposed to ethyl glycol monomethyl ether during manufacturing and packaging had a higher prevalence of anemia, leukopenia, or sterility than an in-plant comparision group, a cross-sectional study was conducted at the Michigan Division of Dow Chemical U.S.A. Blood samples on 65 of 97 potentially exposed and control white males, and semen samples from a subset of 15 were analyzed. With the possible exception of smaller testicular size, no gross abnormalities or clinically meaningful differences in hematological or fertility indices were noted. Results of regression modeling suggested that white blood cells and hemoglobin might be decreased at higher exposure levels.

  7. Evaluation of liquid chromatography column retentivity using macromolecular probes. IV. Poly(ethylene glycol) bonded phase.


    Berek, Dusan; Mendichi, Raniero


    Interaction properties of the novel HPLC silica gel-poly(ethylene glycol) (PEG) bonded phase were evaluated applying polymeric test substances, viz. polystyrenes, poly(methyl methacrylate)s, poly(ethylene oxide)s and poly(2-vinyl pyridine)s, and eluents of different polarities. Silanols on the silica gel surface are well shielded by the PEG phase, and silanophilic adsorption of macromolecules is suppressed in comparison with most silica C(18) bonded phases. The adsorption of solutes on the -OH groups of the PEG phase seems to be low as well. The partition of macromolecules in favor of the PEG phase is inferior to that observed in case of the silica C(18) phases. The volume of the PEG bonded phase is small and it is supposed that the PEG chains assume flat conformation on the silica gel surface. PMID:14698238

  8. Impact compressibility of a poly(ethylene glycol)-based nanocomposite fluid

    NASA Astrophysics Data System (ADS)

    Bragov, A. M.; Igumnov, L. A.; Konstantinov, A. Yu.; Lomunov, A. K.; Antonov, F. K.; Mossakovskii, P. A.


    The behavior of a poly(ethylene glycol)-based nanocomposite shear thickening fluid (STF) under impact loading conditions has been experimentally studied using the Kolsky method and related techniques. The dependence of the pressure in the STF on the volume strain magnitude has been determined. It is established that the radial and axial components of the stress tensor almost coincide, which shows that the material behaves like an incompressible liquid. The character of the stress-strain curves (hysteresis) indicates that the STF is characterized by some energy dissipation in the load-unload cycle.

  9. The properties of electrochromic film electrodes of lanthanide diphthalocyanines in ethylene glycol

    SciTech Connect

    Collins, G.C.S.; Schiffrin, D.J.


    The electrochromic properties of film electrodes of lutetium, erbium, gadolinium, and ytterbium diphthalocyanines in contact with ethylene glycol solutions have been studied. The stability of the electrochromic film under electrochemical cycling in this medium is at least three orders of magnitude better than that in neutral aqueous solutions. The stability of the electrochromic is improved if the film is written galvanostatically from the yellow-tan to the green state. A simplified model for the galvanostatic transition is proposed, and some of the problems of this family of electrochromic materials are discussed.

  10. Reversible subacute ethylene glycol monomethyl ether toxicity associated with microfilm production: a case report

    SciTech Connect

    Cohen, R.


    The first reported case of a possible toxic effect of ethylene glycol monomethyl ether (EGME) exposure in the microfilm manufacturing industry is described. Reversible subjective central nervous system complaints and asymptomatic hematopoietic effects occurred following inhalation and skin exposure to EGME. Hematopoietic changes occurred at airborne levels which have been associated with reproductive and teratogenic effects in other studies. This finding leads to a recommendation for further research to determine whether or not hematopoietic medical surveillance can provide an indication of not only EGME hematopoietic effects but also an indication of sufficient EGME exposure to affect human reproduction and fetal development.

  11. On the structures of ethylene glycol, monoethanolamine, and ethylenediamine in the liquid phase

    NASA Astrophysics Data System (ADS)

    Balabaev, N. K.; Kraevskii, S. V.; Rodnikova, M. N.; Solonina, I. A.


    Characteristics of instant (I) and frozen (F) structures of ethylene glycol (EG), monoethanolamine (MEA), and ethylenediamine (ED) are determined by means of molecular dynamics in the temperature range of 268-443 K. Radial distribution functions are obtained and compared for the I- and F-structures of fluids. Coordination numbers of molecules are calculated and the energies of intermolecular hydrogen bonds are estimated for the studied compounds. The greatest difference between the I- and F-structures is observed in ED, and the least difference is observed in EG. The F-structures are compared to the crystal structures of the studied compounds.

  12. Intra- and intermolecular hydrogen bonds in ethylene glycol, monoethanolamine, and ethylenediamine

    NASA Astrophysics Data System (ADS)

    Krest'yaninov, M. A.; Titova, A. G.; Zaichikov, A. M.


    The structures of ethylene glycol, aminoethanol, ethylenediamine, and their dimers with the formation of hydrogen bonds of different types are optimized by density functional theory (DFT) using hybrid functional B3LYP in the basis of 6-31++G( d,p), 6-311++G(2 d,2 p) and aug-CC-pVTZ. Energies of interactions, hydrogen bond parameters, and oscillation frequency are calculated, and NBO analysis is performed. The types of hydrogen bonds formed in dimers of 1,2-disubstituted ethanes X-CH2-CH2-Y (X, Y = OH, NH2) are established.

  13. Investigation on thermo physical characteristics of ethylene glycol based Al:ZnO nanofluids

    NASA Astrophysics Data System (ADS)

    R, Kiruba.; George, Ritty; M, Gopalakrishnan.; A, Kingson Solomon Jeevaraj.


    The present work describes the experimental aspects of viscosity and thermal conductivity characteristics of nanofluids. Aluminium doped zinc oxide nanostructures were synthesized by chemical precipitation method. Ultrasonic technique is used to disperse the nanostructures in ethylene glycol. Structural and morphological properties of Al doped ZnO nanostructures are characterized using X-ray diffractometer and scanning electron microscopic technique. The effect of concentration and temperature on thermo-physical properties of Al/ZnO nanofluids is also investigated. The experimental results showed there is enhancement in thermal conductivity with rise in temperature which can be utilized for coolant application.

  14. Thermal transport properties of ethylene glycol/N-methylformamide binary mixture based CuO nanofluid

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, M.; Kiruba, R.; Jeevaraj, A. Kingson Solomon


    In this present investigation, we have synthesized copper oxide nanoparticles by solvothermal method and analyzed their rheological behavior and thermal conductivity properties in binary base fluids (Ethylene Glycol+N-Methylformamide) and CuO binary nanofluid at different temperature. The crystalline nature and morphological properties of prepared CuO nanoparticles were characterized using XRD and SEM analysis respectively. The influence of CuO nanoparticles increases the thermal conductivity of binary base fluids. The results suggested that prepared binary nanofluids can be applicable in heat transfer.

  15. Viscosity of copper oxide nanoparticles dispersed in ethylene glycol and water mixture

    SciTech Connect

    Namburu, Praveen K.; Kulkarni, Devdatta P.; Das, Debendra K.; Misra, Debasmita


    Nanofluids are new kinds of fluids engineered by dispersing nanoparticles in base fluids. This paper presents an experimental investigation of rheological properties of copper oxide nanoparticles suspended in 60:40 (by weight) ethylene glycol and water mixture. Nanofluids of particle volume percentage ranging from 0% to 6.12% were tested. The experiments were carried over temperatures ranging from -35 C to 50 C to demonstrate their applicability in cold regions. For the particle volume concentrations tested, nanofluids exhibited Newtonian behavior. An experimental correlation was developed based on the data, which relates viscosity with particle volume percent and the nanofluid temperature. (author)

  16. Investigation on thermo physical characteristics of ethylene glycol based Al:ZnO nanofluids

    SciTech Connect

    Kiruba, R. E-mail:; George, Ritty; Gopalakrishnan, M.; Kingson Solomon Jeevaraj, A.


    The present work describes the experimental aspects of viscosity and thermal conductivity characteristics of nanofluids. Aluminium doped zinc oxide nanostructures were synthesized by chemical precipitation method. Ultrasonic technique is used to disperse the nanostructures in ethylene glycol. Structural and morphological properties of Al doped ZnO nanostructures are characterized using X-ray diffractometer and scanning electron microscopic technique. The effect of concentration and temperature on thermo-physical properties of Al/ZnO nanofluids is also investigated. The experimental results showed there is enhancement in thermal conductivity with rise in temperature which can be utilized for coolant application.

  17. Use of a Rapid Ethylene Glycol Assay: a 4-Year Retrospective Study at an Academic Medical Center.


    Rooney, Sydney L; Ehlers, Alexandra; Morris, Cory; Drees, Denny; Davis, Scott R; Kulhavy, Jeff; Krasowski, Matthew D


    Ethylene glycol (EG) is a common cause of toxic ingestions. Gas chromatography (GC)-based laboratory assays are the gold standard for diagnosing EG intoxication. However, GC requires specialized instrumentation and technical expertise that limits feasibility for many clinical laboratories. The objective of this retrospective study was to determine the utility of incorporating a rapid EG assay for management of cases with suspected EG poisoning. The University of Iowa Hospitals and Clinics core clinical laboratory adapted a veterinary EG assay (Catachem, Inc.) for the Roche Diagnostics cobas 8000 c502 analyzer and incorporated this assay in an osmolal gap-based algorithm for potential toxic alcohol/glycol ingestions. The main limitation is that high concentrations of propylene glycol (PG), while readily identifiable by reaction rate kinetics, can interfere with EG measurement. The clinical laboratory had the ability to perform GC for EG and PG, if needed. A total of 222 rapid EG and 24 EG/PG GC analyses were documented in 106 patient encounters. Of ten confirmed EG ingestions, eight cases were managed entirely with the rapid EG assay. PG interference was evident in 25 samples, leading to 8 GC analyses to rule out the presence of EG. Chart review of cases with negative rapid EG assay results showed no evidence of false negatives. The results of this study highlight the use of incorporating a rapid EG assay for the diagnosis and management of suspected EG toxicity by decreasing the reliance on GC. Future improvements would involve rapid EG assays that completely avoid interference by PG. PMID:26553280

  18. The influence of poly(ethylene glycol) ether tetrasuccinimidyl glutarate on the structural, physical, and biological properties of collagen fibers.


    Sanami, Mohammad; Sweeney, India; Shtein, Zvi; Meirovich, Sigal; Sorushanova, Anna; Mullen, Anne Maria; Miraftab, Mohsen; Shoseyov, Oded; O'Dowd, Colm; Pandit, Abhay; Zeugolis, Dimitrios I


    Various chemical, natural, or synthetic in origin, crosslinking methods have been proposed over the years to stabilise collagen fibers. However, an optimal method has yet to be identified. Herein, we ventured to assess the potential of 4-star poly(ethylene glycol) ether tetrasuccinimidyl glutarate, as opposed to glutaraldehyde (GTA), genipin and carbodiimide, on the structural, physical and biological properties of collagen fibers. The 4-star poly(ethylene glycol) ether tetrasuccinimidyl glutarate induced an intermedium surface smoothness, denaturation temperature and swelling. The 4-star poly(ethylene glycol) ether tetrasuccinimidyl glutarate fibers had significantly higher stress at break values than the carbodiimide fibers, but significantly lower than the GTA and genipin fibers. With respect to strain at break, no significant difference was observed among the crosslinking treatments. The 4-star poly(ethylene glycol) ether tetrasuccinimidyl glutarate fibers exhibited significantly higher cell metabolic activity and DNA concentration that all other crosslinking treatments, promoted consistently cellular elongation along the longitudinal fiber axis and by day 7 they were completely covered by cells. Collectively, this work clearly demonstrates the potential of 4-star poly(ethylene glycol) ether tetrasuccinimidyl glutarate as collagen crosslinker. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 914-922, 2016. PMID:25952265

  19. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2012 CFR


    ... in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the Office of... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No....

  20. 21 CFR 177.1360 - Ethylene-vinyl acetate-vinyl alcohol copolymers.

    Code of Federal Regulations, 2013 CFR


    ... in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the Office of Food... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene-vinyl acetate-vinyl alcohol copolymers... acetate-vinyl alcohol copolymers. Ethylene-vinyl acetate-vinyl alcohol copolymers (CAS Reg. No....

  1. Retention properties of hydrophobically end-capped poly(ethylene glycol)s on a beta-cyclodextrin support.


    Karakasyan, Carole; Millot, Marie-Claude; Jaulmes, Alain; Vidal-Madjar, Claire


    High-performance liquid chromatography (HPLC) was used to examine the retention behavior of monomethoxypoly(ethylene glycol)s bearing one hydrophobic naphthyl end group (Nap-MPEG) on beta-cyclodextrin polymer (poly-beta-CD) immobilized on a silica support, under isocratic elution conditions and using water as mobile phase. Studies of retentions and theoretical plate heights H were conducted at infinite dilution by comparing the behavior of Nap-MPEGs having different molecular weight (750, 1000 and 5000 g/mol). The larger is its molecular size, the lower is the retention of the polymer. The linear increase of H with mobile phase velocity reveals slow mass-transfer kinetics arising from the restricted diffusion into the pores of the support. The complexation constants between the Nap-MPEGs and beta-CD in solution (around 500M(-1)) were determined from the decrease of retention observed by adding increasing concentrations of hydroxypropyl beta-CD into the eluent. The peak profiles in mass-overload conditions were studied by fitting a model based upon bi-Langmuir kinetics which assumes a non-uniform support having two types of binding sites and apparent adsorption rate constants are used to describe mass-transfer kinetics. A three-parameter adsorption equilibrium isotherm was sufficient to account for the modifications of peak shapes observed when increasing amounts of polymer were injected. This result indicates an interaction with a heterogeneous poly-beta-CD support mainly composed of low affinity groups, non-saturable in the range of polymer concentration studied. An upper limit was estimated for the equilibrium constant (<1000 M(-1)) characterizing the affinity of Nap-MPEG for the non-saturable sites of the poly-beta-CD support. Large affinity constants (8-9 x 10(4)M(-1)) were found for the interaction of Nap-MPEGs with a small percentage of active sites. PMID:16828487

  2. Effect of pressure on the structure and dynamics of hydrogen bonds in ethylene glycol-water mixtures: Numerical simulation data

    NASA Astrophysics Data System (ADS)

    Antipova, M. L.; Gurina, D. L.; Makarov, D. M.; Egorov, G. I.; Petrenko, V. E.


    Water-ethylene glycol mixtures containing from 0.002 to 0.998 mole fractions of ethylene glycol at T = 298.15 K and P = 0.1 and 100 MPa are simulated by means of classical molecular dynamics. Such structural and dynamic characteristics of hydrogen bonds as the average number and lifetime, along with the distribution of molecules over the number of hydrogen bonds, are calculated; their changes are analyzed, depending on the mixture's composition and pressure. It is shown that the components are characterized by a high degree of interpenetration and form a uniform infinite hydrogen-bonded cluster over the range of concentrations. It is found that the higher the concentration of ethylene glycol, the greater the stability of all hydrogen bonds. It is concluded that an increase in pressure lowers the number of hydrogen bonds, while the average lifetime of the remaining hydrogen bonds grows.

  3. N-Monosubstituted Methoxy-oligo(ethylene glycol) Carbamate Ester Prodrugs of Resveratrol.


    Mattarei, Andrea; Azzolini, Michele; Zoratti, Mario; Biasutto, Lucia; Paradisi, Cristina


    Resveratrol is a natural polyphenol with many interesting biological activities. Its pharmacological exploitation in vivo is, however, hindered by its rapid elimination via phase II conjugative metabolism at the intestinal and, most importantly, hepatic levels. One approach to bypass this problem relies on prodrugs. We report here the synthesis, characterization, hydrolysis, and in vivo pharmacokinetic behavior of resveratrol prodrugs in which the OH groups are engaged in an N-monosubstituted carbamate ester linkage. As promoiety, methoxy-oligo(ethylene glycol) groups (m-OEG) (CH₃-[OCH₂CH₂]n-) of defined chain length (n = 3, 4, 6) were used. These are expected to modulate the chemico-physical properties of the resulting derivatives, much like longer poly(ethylene glycol) (PEG) chains, while retaining a relatively low MW and, thus, a favorable drug loading capacity. Intragastric administration to rats resulted in the appearance in the bloodstream of the prodrug and of the products of its partial hydrolysis, confirming protection from first-pass metabolism during absorption. PMID:26404221

  4. Synthesis and Characterization of Ethylene Glycol Substituted Poly(phenylene Vinylene) Derivatives

    SciTech Connect

    Wang, H.L.; Cotlet, M.; Wang C.-C.; Tsai, H.; Shih, H.-H.; Jeon, S.; Xu, Z.; Williams, D.; Iyer, S.; Sanchez, T.C.; Wang, L.


    We report the synthesis of a series of water-soluble, fluorescent, conjugated polymers via the Gilch reaction with an overall yield greater than 40%. The yield for the Gilch reaction decreases with the increase in the length of the side chain (ethylene glycol), presumably due to the steric effects inhibiting the linking of monomeric units. The hydrophilic side chain enhances the solubility of the polymer in water and concomitantly leads to a side-chain-dependent conformation and solvent-dependent quantum efficiency. An increase in the ethylene glycol repeat units on the polymer side chain structure results in changes in chain packing, hence the crystallinity evolves from semicrystalline to liquid crystalline to completely amorphous. An increased in the length of the side chain also leads to changes in the polymer-solvent interaction that changes the electronic structure as manifested in the photophysical properties of these polymers. These novel polymers exhibit two glass transition temperatures, which can be readily rationalized by differences in microstructure when casted from hydrophobic and hydrophilic solvents. Cyclic voltammograms of polymer 1d-3d suggests two-electron transfer, as compare to P1 which has one complete redox pair. The potential of having a nanoscaled domain structure and stabilizing two electrons on a polymer chains signifies the potential of these polymers in fabricating electronic and photovoltaic devices.

  5. Interrelation of ethylene glycol, urea and water transport in the red cell.


    Toon, M R; Solomon, A K


    The reflection coefficient, sigma j, which measures the coupling between the jth solute and water transport across a semipermeable membrane, varies between 0 and 1.0. Values of sigma j significantly less than 1.0 provide irreversible thermodynamic proof that there is coupling between the transport of solute and solvent and thus that they share a common pathway. We have developed an improved method for measuring sigma and have used it to determine that sigma ethylene glycol = 0.71 +/- 0.03 and sigma urea = 0.65 +/- 0.03, in agreement with many, but not all, previous determinations. Since both of these values are significantly lower than 1.0, they show that there is a common ethylene glycol/water pathway and a common urea/water pathway. Addition of first one and then two methyl groups to urea increases sigma to 0.89 +/- 0.04 for methylurea and 0.98 +/- 0.4 for 1,3-dimethylurea, consistent with passage through an aqueous pore with a sharp cutoff in the 6-7 A region. PMID:3567182

  6. Comparison of methanol and ethylene glycol oxidation by alloy and Core-Shell platinum based catalysts

    NASA Astrophysics Data System (ADS)

    Kaplan, D.; Burstein, L.; Rosenberg, Yu.; Peled, E.


    Two Core-Shell, RuCore-PtShell and IrNiCore-PtRuShell, XC72-supported catalyst were synthesized in a two-step deposition process with NaBH4 as reducing agent. The structure and composition of the Core-Shell catalysts were determined by EDS, XPS and XRD. Electrochemical characterization was performed with the use of cyclic voltammetry. Methanol and ethylene glycol oxidation activities of the Core-Shell catalysts (in terms of surface and mass activities) were studied at 80 °C and compared to those of a commercial Pt-Ru alloy catalyst. The surface activity of the alloy based catalyst, in the case of methanol oxidation, was found to be superior as a result of optimized surface Pt:Ru composition. However, the mass activity of the PtRu/IrNi/XC72 was higher than that of the alloy based catalyst by ∼50%. Regarding ethylene glycol oxidation, while the surface activity of the alloy based catalyst was slightly higher than that of the Pt/Ru/XC72 catalyst, the latter showed ∼66% higher activities in terms of A g-1 of Pt. These results show the potential of Core-Shell catalysts for reducing the cost of catalysts for DMFC and DEGFC.

  7. Antiurolithiatic and antioxidant activity of Hordeum vulgare seeds on ethylene glycol-induced urolithiasis in rats

    PubMed Central

    Shah, Jignesh G.; Patel, Bharat G.; Patel, Sandip B.; Patel, Ravindra K.


    Objective: The objective was to investigate the antiurolithiatic and antioxidant activity of ethanolic extract of Hordeum vulgare seeds (EHV) on ethylene glycol-induced urolithiasis in Wistar albino rats. Materials and Methods: Urolithiasis was produced in Wistar albino rats by adding 0.75% v/v ethylene glycol (EG) to drinking water for 28 days. The ethanolic extract of Hordeum vulgare seeds (EHV) was assessed for its curative and preventive action in urolithiasis. In preventive treatment, the EHV given from 1st day to 28th day, while in the curative regimen, the EHV was given from 15th day to 28th day. Various renal functional and injury markers such as urine volume, calcium, phosphate, uric acid, magnesium, urea, and oxalate were evaluated using urine, serum, and kidney homogenate. Antioxidant parameters such as lipid peroxidation, superoxide dismutase, and catalase were also determined. Results: The EHV treatment (both preventive and curative) increased the urine output significantly compared to the control. The EHV treatment significantly reduced the urinary excretion of the calcium, phosphate, uric acid, magnesium, urea, and oxalate and increased the excretion of citrate compared to EG control. The increased deposition of stone forming constituents in the kidneys of calculogenic rats were significantly lowered by curative and preventive treatment with EHV. It was also observed that the treatment with EHV produced significant decrease in lipid peroxidation, and increased levels of superoxide dismutase and catalase. Conclusion: These results suggest the usefulness of ethanolic extract of Hordeum vulgare seeds as an antiurolithiatic and antioxidant agent. PMID:23248392

  8. Poly(N-vinylimidazole/ethylene glycol dimethacrylate) for the purification and isolation of phenolic acids.


    Schemeth, Dieter; Noël, Jean-Christophe; Jakschitz, Thomas; Rainer, Matthias; Tessadri, Richard; Huck, Christian W; Bonn, Günther K


    In this study we report the novel polymeric resin poly(N-vinyl imidazole/ethylene glycol dimethacrylate) for the purification and isolation of phenolic acids. The monomer to crosslinker ratio and the porogen composition were optimized for isolating phenolic acids diluted in acetonitrile at normal phase chromatography conditions, first. Acetonitrile serves as polar, aprotic solvent, dissolving phenolic acids but not interrupting interactions with the stationary phase due to the approved Hansen solubility parameters. The optimized resin demonstrated high loading capacities and adsorption abilities particularly for phenolic acids in both, acetonitrile and aqueous solutions. The adsorption behavior of aqueous standards can be attributed to ion exchange effects due to electrostatic interactions between protonated imidazole residues and deprotonated phenolic acids. Furthermore, adsorption experiments and subsequent curve fittings provide information of maximum loading capacities of single standards according to the Langmuir adsorption model. Recovery studies of the optimized polymer in the normal-phase and ion-exchange mode illustrate the powerful isolation properties for phenolic acids and are comparable or even better than typical, commercially available solid phase extraction materials. In order to prove the applicability, a highly complex extract of rosemary leaves was purified by poly(N-vinyl imidazole/ethylene glycol dimethacrylate) and the isolated compounds were identified using UHPLC-qTOF-MS. PMID:26231906

  9. Melting point equations for the ternary system water/sodium chloride/ethylene glycol revisited.


    Benson, James D; Bagchi, Aniruddha; Han, Xu; Critser, John K; Woods, Erik J


    Partial phase diagrams are of considerable utility in the development of optimized cryobiological procedures. Recent theoretical predictions of the melting points of ternary solutions of interest to cryobiology have caused us to re-examine measurements that our group made for the ethylene-glycol-sodium chloride-water phase diagram. Here we revisit our previous experiments by measuring melting points at five ethylene-glycol to sodium chloride ratios (R values; R=5, 10, 15, 30, and 45) and five levels of concentration for each ratio. Melting points were averaged from three measurements and plotted as a function of total solute concentration for each R value studied. The new measurements differed from our original experimental values and agreed with predicted values from both theoretical models. Additionally, the data were fit to the polynomial described in our previous report and the resulting equation was obtained: T(m) = (38.3-2.145 x 10⁻¹ R)w + (81.19 - 2.909×10⁻¹ R)w², where w is the total solute mass fraction. This new equation provided good fits to the experimental data as well as published values and relates the determined polynomial constants to the R value of the corresponding isopleths of the three dimensional phase diagram, allowing the liquids curve for any R value to be obtained. PMID:20955693

  10. Improving enzymatic hydrolysis of corn stover pretreated by ethylene glycol-perchloric acid-water mixture.


    He, Yu-Cai; Liu, Feng; Gong, Lei; Lu, Ting; Ding, Yun; Zhang, Dan-Ping; Qing, Qing; Zhang, Yue


    To improve the enzymatic saccharification of lignocellulosic biomass, a mixture of ethylene glycol-HClO4-water (88.8:1.2:10, w/w/w) was used for pretreating corn stover in this study. After the optimization in oil-bath system, the optimum pretreatment temperature and time were 130 °C and 30 min, respectively. After the saccharification of 10 g/L pretreated corn stover for 48 h, the saccharification rate was obtained in the yield of 77.4 %. To decrease pretreatment temperature and shorten pretreatment time, ethylene glycol-HClO4-water (88.8:1.2:10, w/w/w) media under microwave irradiation was employed to pretreat corn stover effectively at 100 °C and 200 W for 5 min. Finally, the recovered hydrolyzates containing glucose obtained from the enzymatic hydrolysis of pretreated corn stovers could be fermented into ethanol efficiently. These results would be helpful for developing a cost-effective pretreatment combined with enzymatic saccharification of cellulosic materials for the production of lignocellulosic ethanol. PMID:25384544

  11. Recent advances in crosslinking chemistry of biomimetic poly(ethylene glycol) hydrogels

    PubMed Central

    Lin, Chien-Chi


    The design and application of biomimetic hydrogels have become an important and integral part of modern tissue engineering and regenerative medicine. Many of these hydrogels are prepared from synthetic macromers (e.g., poly(ethylene glycol) or PEG) as they provide high degrees of tunability for matrix crosslinking, degradation, and modification. For a hydrogel to be considered biomimetic, it has to recapitulate key features that are found in the native extracellular matrix, such as the appropriate matrix mechanics and permeability, the ability to sequester and deliver drugs, proteins, and or nucleic acids, as well as the ability to provide receptor-mediated cell-matrix interactions and protease-mediated matrix cleavage. A variety of chemistries have been employed to impart these biomimetic features into hydrogel crosslinking. These chemistries, such as radical-mediated polymerizations, enzyme-mediated crosslinking, bio-orthogonal click reactions, and supramolecular assembly, may be different in their crosslinking mechanisms but are required to be efficient for gel crosslinking and ligand bioconjugation under aqueous reaction conditions. The prepared biomimetic hydrogels should display a diverse array of functionalities and should also be cytocompatible for in vitro cell culture and/or in situ cell encapsulation. The focus of this article is to review recent progress in the crosslinking chemistries of biomimetic hydrogels with a special emphasis on hydrogels crosslinked from poly(ethylene glycol)-based macromers. PMID:26029357

  12. Poly(ethylene glycol)-functionalized polymeric microchips for capillary electrophoresis.


    Sun, Xuefei; Li, Dan; Lee, Milton L


    Recently, we reported the synthesis, fabrication, and preliminary evaluation of poly(ethylene glycol) (PEG)-functionalized polymeric microchips that are inherently resistant to protein adsorption without surface modification in capillary electrophoresis (CE). In this study, we investigated the impact of cross-linker purity and addition of methyl methacrylate (MMA) as a comonomer on CE performance. Impure poly(ethylene glycol) diacrylate (PEGDA) induced electroosmotic flow (EOF) and increased the separation time, while the addition of MMA decreased the separation efficiency to approximately 25% of that obtained using microchips fabricated without MMA. Resultant improved microchips were evaluated for the separation of fluorescent dyes, amino acids, peptides, and proteins. A CE efficiency of 4.2 x 10(4) plates for aspartic acid in a 3.5 cm long microchannel was obtained. Chiral separation of 10 different D,L-amino acid pairs was obtained with addition of a chiral selector (i.e., beta-cyclodextrin) in the running buffer. Selectivity (alpha) and resolution (R(s)) for D,L-leucine were 1.16 and 1.64, respectively. Good reproducibility was an added advantage of these PEG-functionalized microchips. PMID:19572700

  13. Hydrogen production through aqueous-phase reforming of ethylene glycol in a washcoated microchannel.


    D'Angelo, M Fernanda Neira; Ordomsky, Vitaly; Paunovic, Violeta; van der Schaaf, John; Schouten, Jaap C; Nijhuis, T Alexander


    Aqueous-phase reforming (APR) of biocarbohydrates is conducted in a catalytically stable washcoated microreactor where multiphase hydrogen removal enhances hydrogen efficiency. Single microchannel experiments are conducted following a simplified model based on the microreactor concept. A coating method to deposit a Pt-based catalyst on the microchannel walls is selected and optimized. APR reactivity tests are performed by using ethylene glycol as the model compound. Optimum results are achieved with a static washcoating technique; a highly uniform and well adhered 5 μm layer is deposited on the walls of a 320 μm internal diameter (ID) microchannel in one single step. During APR of ethylene glycol, the catalyst layer exhibits high stability over 10 days after limited initial deactivation. The microchannel presents higher conversion and selectivity to hydrogen than a fixed-bed reactor. The benefits of using a microreactor for APR can be further enhanced by utilizing increased Pt loadings, higher reaction temperatures, and larger carbohydrates (e.g., glucose). The use of microtechnology for aqueous-phase reforming will allow for a great reduction in the reformer size, thus rendering it promising for distributed hydrogen production. PMID:23592593

  14. Synthesis and photophysicochemical studies of poly(ethylene glycol) conjugated symmetrical and asymmetrical zinc phthalocyanines

    NASA Astrophysics Data System (ADS)

    Dinçer, Hatice; Mert, Humeyra; Çalışkan, Emel; Atmaca, Göknur Yaşa; Erdoğmuş, Ali


    Synthesis and characterization of poly(ethylene glycol) conjugated symmetrical and asymmetrical zinc phthalocyanines (ZnPcs) is described. Copper (I) catalyzed azide-alkyne cycloaddition (CuAAC) click reaction between azide functional methoxypoly(ethylene glycol) (mPEG-N3) and tetra terminal alkynyl substituted ZnPc yields star polymer with ZnPc core. Furthermore, CuAAC click reaction between asymmetrically terminal alkynyl substituted zinc phthalocyanine (aZnPc) and mPEG-N3 yields aZnPc end functionalized PEG. Spectral, photophysical (fluorescence quantum yield), photochemical (singlet oxygen (ΦΔ), and photodegradation quantum yield (Φd) properties of the symmetrically, and asymmetrically PEGylated ZnPcs are investigated to be used as sensitizers in photodynamic therapy (PDT). The quantum yield values of fluorescence (ΦF) and singlet oxygen generation (ΦΔ) for water soluble symmetrically PEGylated ZnPc in aqueous solution are calculated as 0.01 and 0.14 respectively, suggesting its potential as photosensitizer in PDT treatment.

  15. Improvement of thermal properties of water and ethylene glycol by metallic and ceramic dispersion

    NASA Astrophysics Data System (ADS)

    Mishra, Sripooja; Chinara, Manaswini; Nuthalapati, Mohan; Basu, A.


    Owing to rising need for more energy efficient coolant systems, the current work focuses on synthesis of Alumina-water, Alumina-Ethylene Glycol (EG), Zirconium-water, Zirconium-Ethylene Glycol particle dispersion systems for use as quenchants, with varying volume of particles obtained using a top-down approach of 10h ball milling. Characterisation of the particles was performed using XRD analysis, also measuring the crystallite size. Particle size measurement was also undertaken by using particle size analyzer, further corroborated by SEM analysis. A zeta-potential study was carried out to obtain the iso electric point for maintaining stability. Synthesis of the dispersions at different volume % of powders were followed by thermal conductivity measurements with water and EG base fluids, with and without addition of oleic acid as a surfactant. The stability studies were performed by visual observation. From the results it was observed that Al2O3 and Zr can increase conductivity of EG more prominently than water and stability of Zr based suspensions are better than Al2O3. Oleic acid did not play any positive role in these systems.

  16. Rapeseed oil monoester of ethylene glycol monomethyl ether as a new biodiesel.


    Dayong, Jiang; Xuanjun, Wang; Shuguang, Liu; Hejun, Guo


    A novel biodiesel named rapeseed oil monoester of ethylene glycol monomethyl ether is developed. This fuel has one more ester group than the traditional biodiesel. The fuel was synthesized and structurally identified through FT-IR and P(1P)H NMR analyses. Engine test results show that when a tested diesel engine is fueled with this biodiesel in place of 0# diesel fuel, engine-out smoke emissions can be decreased by 25.0%-75.0%, CO emissions can be reduced by 50.0%, and unburned HC emissions are lessened significantly. However, NOx emissions generally do not change noticeably. In the area of combustion performance, both engine in-cylinder pressure and its changing rate with crankshaft angle are increased to some extent. Rapeseed oil monoester of ethylene glycol monomethyl ether has a much higher cetane number and shorter ignition delay, leading to autoignition 1.1°CA earlier than diesel fuel during engine operation. Because of certain amount of oxygen contained in the new biodiesel, the engine thermal efficiency is improved 13.5%-20.4% when fueled with the biodiesel compared with diesel fuel. PMID:21403894

  17. Mechanics of semiflexible chains formed by poly(ethylene glycol)-linked paramagnetic particles.


    Biswal, Sibani Lisa; Gast, Alice P


    Magnetorheological particles, permanently linked into chains, provide a magnetically actuated means to manipulate microscopic fluid flow. Paramagnetic colloidal particles form reversible chains by acquiring dipole moments in the presence of an external magnetic field. By chemically connecting paramagnetic colloidal particles, flexible magnetoresponsive chains can be created. We link the paramagnetic microspheres using streptavidin-biotin binding. Streptavidin coated microspheres are placed in a flow cell and a magnetic field is applied, causing the particles to form chains. Then a solution of polymeric linkers of bis-biotin-poly(ethylene glycol) molecules is added in the presence of the field. These linked chains remain responsive to a magnetic field; however, in the absence of an external magnetic field these chains bend and flex due to thermal motion. The chain flexibility is determined by the length of the spacer molecule between particles and is quantified by the flexural rigidity or bending stiffness. To understand the mechanical properties of the chains, we use a variety of optical trapping experiments to measure the flexural rigidity. Increasing the length of the poly(ethylene glycol) chain in the linker increases the flexibility of the chains. PMID:14524968

  18. Effect of Unex on ethylene glycol-induced urolithiasis in rats

    PubMed Central

    Jarald, Elias Edwin; Kushwah, Pankaj; Edwin, Sheeja; Asghar, Suhail; Patni, Showkat Ahmad


    This study was aimed to evaluate the effectiveness of the Unex capsule on albino rats as a preventive agent against the development of kidney stones. The Unex capsule is a marketed product of Unijules Life Sciences, Nagpur, containing the extracts of Boerhaavia diffusa and Tribulus terrestris. Activity of Unex was studied using the ethylene glycol-induced urolithiasis model. Standard drug used was Cystone. Several parameters were used including urinary volume, urine pH, urine analysis, and serum analysis to assess the activity. The results indicated that the administration of Unex to rats with ethylene glycol-induced lithiasis significantly reduced and prevented the growth of urinary stones (P < 0.01). Also, the treatment of lithiasis-induced rats by Unex restored all the elevated biochemical parameters (creatinine, uric acid, and blood urea nitrogen), restored the urine pH to normal, and increased the urine volume significantly (P < 0.01) when compared to the model control drug. This study supports the usage of Unex in urolithiasis and the utility could further be confirmed in other animal models. PMID:21845008

  19. Alcea rosea root extract as a preventive and curative agent in ethylene glycol-induced urolithiasis in rats

    PubMed Central

    Ahmadi, Marzieh; Rad, Abolfazl Khajavi; Rajaei, Ziba; Hadjzadeh, Mousa-Al-Reza; Mohammadian, Nema; Tabasi, Nafiseh Sadat


    Introduction: Alcea rosea L. is used in Asian folk medicine as a remedy for a wide range of ailments. The aim of the present study was to investigate the effect of hydroalcoholic extract of Alcea rosea roots on ethylene glycol-induced kidney calculi in rats. Materials and Methods: Male Wistar rats were randomly divided into control, ethylene glycol (EG), curative and preventive groups. Control group received tap drinking water for 28 days. Ethylene glycol (EG), curative and preventive groups received 1% ethylene glycol for induction of calcium oxalate (CaOx) calculus formation; preventive and curative subjects also received the hydroalcoholic extract of Alcea rosea roots in drinking water at dose of 170 mg/kg, since day 0 or day 14, respectively. Urinary oxalate concentration was measured by spectrophotometer on days 0, 14 and 28. On day 28, the kidneys were removed and examined histopathologically under light microscopy for counting the calcium oxalate deposits in 50 microscopic fields. Results: In both preventive and curative protocols, treatment of rats with hydroalcoholic extract of Alcea rosea roots significantly reduced the number of kidney calcium oxalate deposits compared to ethylene glycol group. Administration of Alcea rosea extract also reduced the elevated urinary oxalate due to ethylene glycol. Conclusion: Alcea rosea showed a beneficial effect in preventing and eliminating calcium oxalate deposition in the rat kidney. This effect is possibly due to diuretic and anti-inflammatory effects or presence of mucilaginous polysaccharides in the plant. It may also be related to lowering of urinary concentration of stone-forming constituents. PMID:22701236

  20. Synthesis and characterization of poly(D,L-lactide)-poly(ethylene glycol) multiblock poly(ether-ester-urethane)s

    NASA Astrophysics Data System (ADS)

    Haw, Tan Ching; Ahmad, Azizan; Anuar, Farah Hannan


    In this study, poly(D,L-lactide)-poly(ethylene glycol) multiblock poly(ether-ester-urethane)s was synthesized in the framework of environmental friendly products to meet the need for highly flexible polymers. Triblock copolymer with poly(ethylene glycol) as center block and poly(D,L-lactide) as side block were first synthesized by ring-opening polymerization of D,L-lactide, followed by chain extension reaction of triblocks using hexamethylene diisocyanate (HMDI). NMR and infra-red spectroscopies were used to determine the molecular composition whereas XRD analysis revealed crystallinity behavior of synthesized multiblock copolymers.

  1. Effect of Micellar Aggregate on the Kinetics and Mechanism of the Reaction between Ethylene Glycol and Periodate

    PubMed Central

    Segun Esan, Olaseni


    The oxidation of ethylene glycol by periodate (IO4−) was studied in different micellar aggregates of cetyltrimethylammonium bromide (CTABr) and dodecylamine (DA) by means of UV/Vis spectroscopy. The observed constant Ko was obtained by monitoring the disappearing of ethylene glycol with time at a suitable wavelength under pseudofirst condition. Addition of CTABr and DA inhibits the reaction rate while the kinetic behavior was explained on the association of one of the reactants with the micelles leaving the other reactant in the bulk solution (pseudophase model).

  2. Cellulose nanocrystal-poly(oligo(ethylene glycol) methacrylate) brushes with tunable LCSTs.


    Grishkewich, Nathan; Akhlaghi, Seyedeh Parinaz; Zhaoling, Yao; Berry, Richard; Tam, Kam C


    This paper reports on the synthesis of poly(oligoethylene glycol) methyl ether acrylate (POEGMA) grafted cellulose nanocrystals (CNCs) via surface initiated atom transfer radical polymerization (ATRP). An ATRP initiator (α-Bromoisobutyryl bromide) was covalently bonded to the surface of CNCs, followed by copolymerizing di(ethylene glycol) methyl ether methacrylate (MEO2MA) and oligoethylene glycol methyl ether methacrylate (OEGMA300) monomers from the surface using Cu(I)Br/2,2-dipyridal. Multiple POEGMA-g-CNC systems with varying MEO2MA/OEGMA300 content were synthesized, and they displayed a range of lower critical solution temperatures (LCSTs) in aqueous medium. μDSC endotherms and microstructural analysis indicated the collapse of POEGMA chains, followed by the aggregation of nanoparticles above their LCSTs. Cloud point measurements demonstrated a hysteresis in the heating and cooling of the POEGMA-g-CNC systems. It was found that the LCST of the nanoparticles could be tuned to between 23.8 to 63.8°C by adjusting the OEGMA300 content of the POEGMA brushes. PMID:27083811

  3. Atmospheric chemistry of toxic contaminants 2. Saturated aliphatics: Acetaldehyde, dioxane, ethylene glycol ethers, propylene oxide

    SciTech Connect

    Grosjean, D. )


    Detailed mechanisms are outlined for the chemical reactions that contribute to in-situ formation and atmospheric removal of the saturated aliphatic contaminants acetaldehyde, dioxane, ethylene glycol ethers (methyl, ethyl, n-butyl) and propylene oxide. In-situ formation is of major importance for acetaldehyde. In-situ removal involves reaction with OH (all compounds) and, for acetaldehyde, photolysis and reaction with NO{sub 3}. Acetaldehyde, dioxane, and the ethers are rapidly removed (half-lives of less than one day), leading to PAN (acetaldehyde) and to 2-oxodioxane and formaldehyde (dioxane). Reaction products of the glycol ethers include a large number of hydroxyesters, hydroxyacids, and hydroxycarbonyls. Propylene oxide reacts only slowly with OH, with an atmospheric half-life of 3 - 10 days, to yeild formaldehyde, acetaldehyde, and PAN. Uncertainties in the reaction mechanisms for dioxane, the glycol ethers, and propylene oxide are discussed and include C-C vs C-O bond scission in alkoxy radicals as well as alkoxy radical unimolecular decomposition vs reaction with oxygen.

  4. Dehydration and Dehydrogenation of Ethylene Glycol on Rutile TiO2(110)

    SciTech Connect

    Li, Zhenjun; Kay, Bruce D.; Dohnalek, Zdenek


    The interactions of ethylene glycol (EG) with partially reduced rutile TiO2(110) surface have been studied using temperature programmed desorption (TPD). The saturation coverage on the surface Ti rows is determined to be 0.43 monolayer (ML), slightly less than one EG per two Ti sites. Most of the adsorbed ethanol (~80%) undergoes further reactions to other products. Two major channels are observed, dehydration yielding ethylene and water and dehydrogenation yielding acetaldehyde and hydrogen. Hydrogen formation is rather surprising as it has not been observed previously on TiO2(110) from simple organic molecules. The coverage dependent yields of ethylene and acetaldehyde correlate well with that of water and hydrogen, respectively. Dehydration dominates at lower EG coverages (< 0.2 ML) and plateaus as the coverage is increased to saturation. Dehydrogenation is observed primarily at higher EG coverages (>0.2 ML). Our results suggest that the observed dehydration and dehydrogenation reactions proceed via different surface intermediates.

  5. Detection and quantitative determination of diethylene glycol in ethyl alcohol using gamma- ray spectroscopy.


    Udagani, Chikkappa; Ramesh, Thimmasandra Narayan


    Determination of the toxic diethylene glycol contamination in ethyl alcohol demands a rapid, accurate and reliable method. Diethylene glycol (DEG) ingestion, accidental or intentional, can lead to death. Clinical and analytical methods used to detect diethylene glycol in alcohol require several hours to days due to tedious instrument handling and measurements. Enzymatic assays face difficulty due to analytic problems. As an alternative method of data analysis, we have used γ-ray spectroscopic method to estimate the diethylene glycol contamination in alcohol by monitoring the variation in the linear and mass attenuation coefficients. This method is simple, robust, portable and can provide reliable and quantitative information about the ethyl alcohol adulterated with diethylene glycol which is of broader interest to society. PMID:26243958

  6. A poly(ethylene glycol)-based surfactant for formulation of drug-loaded mucus penetrating particles.


    Mert, Olcay; Lai, Samuel K; Ensign, Laura; Yang, Ming; Wang, Ying-Ying; Wood, Joseph; Hanes, Justin


    Mucosal surfaces are protected by a highly viscoelastic and adhesive mucus layer that traps most foreign particles, including conventional drug and gene carriers. Trapped particles are eliminated on the order of seconds to hours by mucus clearance mechanisms, precluding sustained and targeted drug and nucleic acid delivery to mucosal tissues. We have previously shown that polymeric coatings that minimize adhesive interactions with mucus constituents lead to particles that rapidly penetrate human mucus secretions. Nevertheless, a particular challenge in formulating drug-loaded mucus penetrating particles (MPP) is that many commonly used surfactants are either mucoadhesive, or do not facilitate efficient drug encapsulation. We tested a novel surfactant molecule for particle formulation composed of Vitamin E conjugated to 5 kDa poly(ethylene glycol) (VP5k). We show that VP5k-coated poly(lactide-co-glycolide) (PLGA) nanoparticles rapidly penetrate human cervicovaginal mucus, whereas PLGA nanoparticles coated with polyvinyl alcohol or Vitamin E conjugated to 1 kDa PEG were trapped. Importantly, VP5k facilitated high loading of paclitaxel, a frontline chemo drug, into PLGA MPP, with controlled release for at least 4 days and negligible burst release. Our results offer a promising new method for engineering biodegradable, drug-loaded MPP for sustained and targeted delivery of therapeutics at mucosal surfaces. PMID:21911015

  7. 40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

    Code of Federal Regulations, 2010 CFR


    ... ether from the list of hazardous air pollutants. 63.63 Section 63.63 Protection of Environment... AIR POLLUTANTS FOR SOURCE CATEGORIES List of Hazardous Air Pollutants, Petitions Process, Lesser... list of hazardous air pollutants. The substance ethylene glycol monobutyl ether...

  8. Si-C linked oligo(ethylene glycol) layers in silicon-based photonic crystals: optimization for implantable optical materials.


    Kilian, Kristopher A; Böcking, Till; Gaus, Katharina; Gal, Michael; Gooding, J Justin


    Porous silicon has shown potential for various applications in biology and medicine, which require that the material (1) remain stable for the length of the intended application and (2) resist non-specific adsorption of proteins. Here we explore the efficacy of short oligo(ethylene glycol) moieties incorporated into organic layers via two separate strategies in achieving these aims. In the first strategy the porous silicon structure was modified in a single step via hydrosilylation of alpha-oligo(ethylene glycol)-omega-alkenes containing three or six ethylene glycol units. The second strategy employs two steps: (1) hydrosilylation of succinimidyl-10-undecenoate and (2) coupling of an amino hexa(ethylene glycol) species. The porous silicon photonic crystals modified by the two-step strategy displayed greater stability relative to the single step procedure when exposed to conditions of physiological temperature and pH. Both strategies produced layers that resist non-specific adsorption of proteins as determined with fluorescently labelled bovine serum albumin. The antifouling behaviour and greater stability to physiological conditions provided by this chemistry enhances the suitability of porous silicon for biomaterials applications. PMID:17428533

  9. Facile synthesis of porous worm-like Pd nanotubes with high electrocatalytic activity and stability towards ethylene glycol oxidation.


    Feng, Jiu-Ju; Zhou, Dan-Ling; Xi, Huan-Xiang; Chen, Jian-Rong; Wang, Ai-Jun


    A facile method was developed for large-scale preparation of porous worm-like Pd nanotubes based on the reduction of PdO nanotubes, which were obtained by calcining the complex precipitate of [Pd(dimethylglyoxime)2]n. The Pd catalyst showed excellent electrocatalytic activity and stability towards ethylene glycol oxidation. PMID:23817778

  10. AuPd/polyaniline as the anode in an ethylene glycol microfluidic fuel cell operated at room temperature.


    Arjona, N; Palacios, A; Moreno-Zuria, A; Guerra-Balcázar, M; Ledesma-García, J; Arriaga, L G


    AuPd/polyaniline was used for the first time, for ethylene glycol (EG) electrooxidation in a novel microfluidic fuel cell (MFC) operated at room temperature. The device exhibits high electrocatalytic performance and stability for the conversion of cheap and fully available EG as fuel. PMID:24923468

  11. 40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

    Code of Federal Regulations, 2012 CFR


    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants. 63.63 Section 63.63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR...

  12. 40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

    Code of Federal Regulations, 2011 CFR


    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants. 63.63 Section 63.63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR...

  13. 40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

    Code of Federal Regulations, 2013 CFR


    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants. 63.63 Section 63.63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR...


    EPA Science Inventory

    Bulk syntheses of silver (Ag) and iron (Fe) nanorods using poly (ethylene glycol), PEG, under microwave irradiation (MW) conditions are reported. Favorable conditions to make Ag nanorods were established and can be extended to make Fe nanorods with uniform size and shape. The nan...

  15. 40 CFR 721.10515 - Partially fluorinated alcohol substituted glycols (generic).

    Code of Federal Regulations, 2014 CFR


    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Partially fluorinated alcohol... New Uses for Specific Chemical Substances § 721.10515 Partially fluorinated alcohol substituted... substances identified generically as partially fluorinated alcohol substituted glycols (PMN P-10-58,...

  16. Engineering a novel biosynthetic pathway in Escherichia coli for production of renewable ethylene glycol.


    Pereira, Brian; Zhang, Haoran; De Mey, Marjan; Lim, Chin Giaw; Li, Zheng-Jun; Stephanopoulos, Gregory


    Ethylene glycol (EG) is an important commodity chemical with broad industrial applications. It is presently produced from petroleum or natural gas feedstocks in processes requiring consumption of significant quantities of non-renewable resources. Here, we report a novel pathway for biosynthesis of EG from the renewable sugar glucose in metabolically engineered Escherichia coli. Serine-to-EG conversion was first achieved through a pathway comprising serine decarboxylase, ethanolamine oxidase, and glycolaldehyde reductase. Serine provision in E. coli was then enhanced by overexpression of the serine-biosynthesis pathway. The integration of these two parts into the complete EG-biosynthesis pathway in E. coli allowed for production of 4.1 g/L EG at a cumulative yield of 0.14 g-EG/g-glucose, establishing a foundation for a promising biotechnology. PMID:26221864

  17. Sizing the Bacillus anthracis PA63 Channel with Nonelectrolyte Poly(Ethylene Glycols)

    PubMed Central

    Nablo, Brian J.; Halverson, Kelly M.; Robertson, Joseph W. F.; Nguyen, Tam L.; Panchal, Rekha G.; Gussio, Rick; Bavari, Sina; Krasilnikov, Oleg V.; Kasianowicz, John J.


    Nonelectrolyte polymers of poly(ethylene glycol) (PEG) were used to estimate the diameter of the ion channel formed by the Bacillus anthracis protective antigen 63 (PA63). Based on the ability of different molecular weight PEGs to partition into the pore and reduce channel conductance, the pore appears to be narrower than the one formed by Staphylococcus aureus α-hemolysin. Numerical integration of the PEG sample mass spectra and the channel conductance data were used to refine the estimate of the pore's PEG molecular mass cutoff (∼1400 g/mol). The results suggest that the limiting diameter of the PA63 pore is <2 nm, which is consistent with an all-atom model of the PA63 channel and previous experiments using large ions. PMID:18645196

  18. Structure of phospholipid monolayers containing poly(ethylene glycol) lipids at the air-water interface

    SciTech Connect

    Majewski, J.; Smith, G.S.; Kuhl, T.L.; Israelachvili, J.N.; Gerstenberg, M.C.


    The density distribution of a lipid monolayer at the air-water interface mixed with varying amounts of lipid with poly(ethylene glycol)polymer headgroups (polymer-lipid or PEG-lipid) was measured using neutron reflectometry. The structure of the monolayer at the interface was greatly perturbed by the presence of the bulky polymer-lipid headgroups resulting in a large increase in the thickness of the headgroup region normal to the interface and a systematic roughening of the interface with increasing polymer-lipid content. These results show how bulky hydrophilic moieties cause significant deformations and out-of-place protrusions of phospholipid monolayers and presumably bilayers, vesicles and biological membranes. In terms of polymer physics, very short polymer chains tethered to the air-water interface follow scaling behavior with a mushroom to brush transition with increasing polymer grafting density. 34 refs., 9 figs., 1 tab.

  19. Single molecule force spectroscopy by AFM indicates helical structure of poly(ethylene-glycol) in water

    NASA Astrophysics Data System (ADS)

    Oesterhelt, F.; Rief, M.; Gaub, H. E.


    We elongated individual poly(ethylene-glycol) (PEG) molecules tethered at one end to an AFM cantilever. We observed the resistive force as a function of elongation in different solvents. In all cases the molecular response was found to be fully reversible and thus in thermodynamic equilibrium. In hexadecane the stretched PEG acts like an ideal entropy spring and can be well described as a freely jointed chain. In water we observed marked deviations in the transition region from entropic to enthalpic elasticity, indicating the deformation of a supra-structure within the polymer. An analysis based on elastically coupled Markovian two-level systems agrees well with recent ab initio calculations predicting that PEG in water forms a non-planar supra-structure which is stabilized by water bridges. We obtained a binding free energy of 3.0+/-0.3 kT.

  20. Multi-armed cationic cyclodextrin:poly(ethylene glycol) polyrotaxanes as efficient gene silencing vectors†

    PubMed Central

    Kulkarni, Aditya; DeFrees, Kyle; Schuldt, Ryan A.; Vlahu, Alexander; VerHeul, Ross; Hyun, Seok-Hee; Deng, Wei


    A family of branched polyrotaxanes (bPRTx+), threaded with multiple cationic α-cyclodextrins (α-CDs) onto a multi-armed poly(ethylene glycol) (PEG) core, were synthesized and studied as gene silencing vectors. These bPRTx+ formed stable, positively charged complexes with diameters of 150–250 nm at N/P ratios as low as 2.5. The bPRTx+ materials were shown to have gene-silencing efficiencies comparable to those of Lipofectamine 2000 (L2k) and bPEI, while displaying similar toxicity profiles. The unique structure of these polyrotaxanes allows them to effectively condense and complex siRNA into nanoparticles at much lower N/P ratios than L2k or bPEI. These findings suggest that bPRTx+ may be useful materials for gene therapy applications. PMID:23042106

  1. Protein resistance of surfaces modified with oligo(ethylene glycol) aryl diazonium derivatives.


    Fairman, Callie; Ginges, Joshua Z; Lowe, Stuart B; Gooding, J Justin


    Anti-fouling surfaces are of great importance for reducing background interference in biosensor signals. Oligo(ethylene glycol) (OEG) moieties are commonly used to confer protein resistance on gold, silicon and carbon surfaces. Herein, we report the modification of surfaces using electrochemical deposition of OEG aryl diazonium salts. Using electrochemical and contact angle measurements, the ligand packing density is found to be loose, which supports the findings of the fluorescent protein labelling that aryl diazonium OEGs confer resistance to nonspecific adsorption of proteins albeit lower than alkane thiol-terminated OEGs. In addition to protein resistance, aryl diazonium attachment chemistry results in stable modification. In common with OEG species on gold electrodes, OEGs with distal hydroxyl moieties do confer superior protein resistance to those with a distal methoxy group. This is especially the case for longer derivatives where superior coiling of the OEG chains is possible. PMID:23650106

  2. Study on thermodynamics and oxidation mechanism of ethylene glycol in the preparation of nanometer nickel powders

    SciTech Connect

    Jin Shengming . E-mail:; Yuan Liangsheng; Zhou Ying; Qiu Guanzhou; Wan Cuifeng


    Nanometer nickel powders have been prepared using the polyol method with NaOH, Ni(NO{sub 3}){sub 2}.6H{sub 2}O, ethylene glycol (EG), and polyvinylpyrrolidone (PVP) as raw materials. The thermodynamics of the reaction system was studied, and the E-pH diagram of Ni-EG-H{sub 2}O was plotted. The oxidation products of EG were predicted from the E-pH diagram, and CO{sub 3} {sup 2-} in alkaline solutions was identified as the product through the IR spectrum and CaCO{sub 3} sediment. Field-emission scanning electron micrograph (FE-SEM) showed that spherical nanometer nickel powders were obtained.

  3. Effect of incorporation of ethylene glycol into PEDOT:PSS on electron phonon coupling and conductivity

    NASA Astrophysics Data System (ADS)

    Lin, Yow-Jon; Ni, Wei-Shih; Lee, Jhe-You


    The effect of incorporation of ethylene glycol (EG) into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) on electron phonon coupling and conductivity is investigated. It is shown that the carrier density (NC) increases significantly and the carrier mobility (μ) increases slightly at 300 K. The increased intensity of the Raman spectrum between 1400 and 1450 cm-1, following EG treatment (that is, the quinoid-dominated structures of the PEDOT chain), leads to an increase in the number of polarons (bipolarons), which leads to an increase in NC. In addition, μ in PEDOT:PSS samples with or without EG addition exhibits a strong temperature dependence, which demonstrates the dominance of tunneling (hopping) at low (high) temperatures. The high conductivity of PEDOT:PSS samples with the addition of EG is attributed to the combined effect of the modification of the electron-phonon coupling and the increase in NC (μ).

  4. Pulsed high-voltage dielectric properties of ethylene glycol/water mixtures

    NASA Astrophysics Data System (ADS)

    Fenneman, David B.


    Measurements of the (complex) dielectric constant, intrinsic time constant, and electrical breakdown strength of highly purified ethylene glycol/water mixtures as functions of temperature and mixture ratio are presented. Over the frequency range from 0.5 to 108 MHz, the dielectric constant is found to be well represented by a simple Debye model. When cooled to near their freezing points, these mixtures have dielectric constants of the same order as pure water (˜80) but with intrinsic time constants at least an order of magnitude greater than water. The mixtures are found to support fields greater than 15 MV/m for periods exceeding a millisecond. The observed high-voltage decay is nonsimple due to the phenomenon of charge injection. The ability to sustain high fields for millisecond time scales suggests the use of such mixtures as the dielectric in the pulse forming lines of large-pulse power machines.

  5. Inhibition of Corrosion of 3003 Aluminum Alloy in Ethylene Glycol-Water Solutions

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Cheng, Y. F.


    In this study, the inhibiting effects of four types of inhibitors, including gluconate, cinnamate, molybdate, and nitrate, on corrosion of a 3003 aluminum (Al) alloy were investigated in ethylene glycol-water solutions that simulate the automotive coolant by various electrochemical measurements. It was found that the tested inhibitors were effective to inhibit corrosion of 3003 Al alloy under both static and turbulent flow conditions. They all behave as anodic inhibitors, which inhibit the Al alloy corrosion by passivating Al alloy and decreasing its anodic current density. A turbulent flow of the solution decreases the corrosion resistance of Al alloy and the inhibiting effect of the inhibitors. The inhibiting effect of the inhibitors is ranked as: nitrate > cinnamate > gluconate > molybdate.

  6. Catalytic conversion of cellulosic biomass to ethylene glycol: Effects of inorganic impurities in biomass.


    Pang, Jifeng; Zheng, Mingyuan; Sun, Ruiyan; Song, Lei; Wang, Aiqin; Wang, Xiaodong; Zhang, Tao


    The effects of typical inorganic impurities on the catalytic conversion of cellulose to ethylene glycol (EG) were investigated, and the mechanism of catalyst deactivation by certain impurities were clarified. It was found that most impurities did not affect the EG yield, but some non-neutral impurities or Ca and Fe ions greatly decreased the EG yield. Conditional experiments and catalyst characterization showed that some impurities changed the pH of the reaction solution and affected the cellulose hydrolysis rate; Ca and Fe cations reacted with tungstate ions and suppressed the retro-aldol condensation. To obtain a high EG yield, the pH of the reaction solution and the concentration of tungstate ions should be respectively adjusted to 5.0-6.0 and higher than 187ppm. For raw biomass conversion, negative effects were eliminated by suitable pretreatments, and high EG yields comparable to those from pure cellulose were obtained. PMID:25459851

  7. Poly(ethylene glycol)-Prodrug Conjugates: Concept, Design, and Applications

    PubMed Central

    Banerjee, Shashwat S.; Aher, Naval; Patil, Rajesh; Khandare, Jayant


    Poly(ethylene glycol) (PEG) is the most widely used polymer in delivering anticancer drugs clinically. PEGylation (i.e., the covalent attachment of PEG) of peptides proteins, drugs, and bioactives is known to enhance the aqueous solubility of hydrophobic drugs, prolong circulation time, minimize nonspecific uptake, and achieve specific tumor targetability through the enhanced permeability and retention effect. Numerous PEG-based therapeutics have been developed, and several have received market approval. A vast amount of clinical experience has been gained which has helped to design PEG prodrug conjugates with improved therapeutic efficacy and reduced systemic toxicity. However, more efforts in designing PEG-based prodrug conjugates are anticipated. In light of this, the current paper highlights the synthetic advances in PEG prodrug conjugation methodologies with varied bioactive components of clinical relevance. In addition, this paper discusses FDA-approved PEGylated delivery systems, their intended clinical applications, and formulations under clinical trials. PMID:22645686

  8. Poly(ethylene glycol) diacrylate-supported ionogels with consistent capacitive behavior and tunable elastic response.


    Visentin, Adam F; Panzer, Matthew J


    Harnessing the many favorable properties of ionic liquids in a solid electrolyte thin film form is desirable for a host of electrical energy storage applications, including electrochemical double layer capacitors. Using a cross-linked polymer matrix to provide structural support, freestanding ionogel materials can be achieved with a wide range of polymer weight fractions. Compression testing and impedance spectroscopy have been used to characterize the mechanical and electrical responses of ionogels containing between 4.9 and 44.7 wt % poly(ethylene glycol) diacrylate. Although the elastic modulus of these solid electrolyte materials is observed to vary by more than 4 orders of magnitude within the composition range studied, concomitant changes in gel ionic conductivity and double layer capacitance were much less dramatic. PMID:22583832

  9. Controllable growth of dendrite-like CuO nanostructures by ethylene glycol assisted hydrothermal process

    SciTech Connect

    Zhang Hui; Li Shenzhong; Ma Xiangyang; Yang Deren


    The dendrite-like CuO nanostructures, consisting of a rod-like main stem and some rod-like sub-branches, have been synthesized by a simple ethylene glycol (EG) assisted hydrothermal method. The X-ray diffraction (XRD) and the selected area electron diffraction (SAED) patterns indicate that the dendrite-like CuO nanostructures are of monoclinic phase and the individual branch of CuO is single crystalline in nature. The effects of the growth conditions such as temperature and pH value on the morphology and structures of CuO have also been investigated. It is indicated that different temperature and pH value result in the morphology and structure evolution of CuO. Moreover, a possible mechanism for the morphology and structures evolution of CuO has been primarily presented.

  10. Rheological and volumetric properties of TiO2-ethylene glycol nanofluids

    PubMed Central


    Homogeneous stable suspensions obtained by dispersing dry TiO2 nanoparticles in pure ethylene glycol were prepared and studied. Two types of nanocrystalline structure were analyzed, namely anatase and rutile phases, which have been characterized by scanning electron microscopy. The rheological behavior was determined for both nanofluids at nanoparticle mass concentrations up to 25%, including flow curves and frequency-dependent storage and loss moduli, using a cone-plate rotational rheometer. The effect of temperature over these flow curve tests at the highest concentration was also analyzed from 283.15 to 323.15 K. Furthermore, the influence of temperature, pressure, nanocrystalline structure, and concentration on the volumetric properties, including densities and isobaric thermal expansivities, were also analyzed. PMID:23763850

  11. Rheological non-Newtonian behaviour of ethylene glycol-based Fe2O3 nanofluids

    PubMed Central


    The rheological behaviour of ethylene glycol-based nanofluids containing hexagonal scalenohedral-shaped α-Fe2O3 (hematite) nanoparticles at 303.15 K and particle weight concentrations up to 25% has been carried out using a cone-plate Physica MCR rheometer. The tests performed show that the studied nanofluids present non-Newtonian shear-thinning behaviour. In addition, the viscosity at a given shear rate is time dependent, i.e. the fluid is thixotropic. Finally, using strain sweep and frequency sweep tests, the storage modulus G', loss modulus G″ and damping factor were determined as a function of the frequency showing viscoelastic behaviour for all samples. PMID:22027018

  12. Antifreeze in the hot core of Orion. First detection of ethylene glycol in Orion-KL

    NASA Astrophysics Data System (ADS)

    Brouillet, N.; Despois, D.; Lu, X.-H.; Baudry, A.; Cernicharo, J.; Bockelée-Morvan, D.; Crovisier, J.; Biver, N.


    Context. Ices are present in comets and in the mantles of interstellar grains. Their chemical composition has been indirectly derived by observing molecules released in the gas phase, when comets approach the sun and when ice mantles are sublimated or destroyed, e.g. in the hot cores present in high-mass, star-forming regions. Comparison of these chemical compositions sheds light on the formation of comets and on the evolution of interstellar matter from the molecular cloud to a protoplanetary disk, and it shows, to first order, a good agreement between the cometary and interstellar abundances. However, a complex O-bearing organic molecule, ethylene glycol (CH2OH)2, seems to depart from this correlation because it was not easily detected in the interstellar medium (Sgr B2) although it proved to be rather abundant with respect to other O-bearing species in comet C/1995 O1 (Hale-Bopp). Ethylene glycol thus appears, together with the closely related molecules glycolaldehyde CH2OHCHO and ethanol CH3CH2OH, as a key species in the comparison of interstellar and cometary ices as well as in any discussion on the formation of cometary matter. Aims: It is important to measure the molecular abundances in various hot cores to see if the observed differences between the interstellar medium and the comets are general. We focus here on the analysis of ethylene glycol in the nearest and best studied hot core-like region, Orion-KL. Methods: We use ALMA interferometric data because high spatial resolution observations allow us to reduce the line confusion problem with respect to single-dish observations since different molecules are expected to exhibit different spatial distributions. Furthermore, a large spectral bandwidth is needed because many individual transitions are required to securely detect large organic molecules. Confusion and continuum subtraction are major issues and have been handled with care. Results: We have detected the aGg' conformer of ethylene glycol in Orion

  13. Spectral Reflectance of Duckweed (Lemna Gibba L.) Fronds Exposed to Ethylene Glycol

    NASA Technical Reports Server (NTRS)

    Dong, Weijin; Carter, Gregory A.; Barber, John T.


    When duckweed (Lemna Gibba L.) fronds are exposed to ethylene glycol (EG) anatomy is altered, allowing an increase in water uptake that causes a darkening of frond appearance. Spectroradiometry was used to quantify changes in frond reflectance that occurred throughout the 400-850 nm spectrum under various EG concentrations and exposure times. The threshold concentration of EG at which a reflectance change could be detected was between 35 and 40 mM, approximately the same as by visual observation. EG-induced changes in frond reflectance were maximum at concentrations of 50 mM or greater. Reflectance changes were detectable within 24h of exposure to 100 mM EG,2-3 days prior to changes in frond appearance. The spectroradiometry of duckweed may serve as a rapid and sensitive technique for detection of ecosystem exposure to EG and perhaps other stress agents.

  14. Poly(ethylene glycol)-polypeptide Copolymer Micelles for Therapeutic Agent Delivery.


    Cheng, Yilong


    Poly(ethylene glycol)-polypeptide (PEG-polypeptide) based polymeric micelles as therapeutic agent carriers have received considerable interest due to their advanced achievements in clinical trials. Polypeptides not only show well-defined secondary structure (alfa-helix and beta-sheet) and good biocompatibility, but can also be functionalized with various groups by direct N-carboxyanhydrides (NCAs) polymerization or further modification. Additionally, the ionizable side chains enable them to deliver diverse therapeutic agents, such as negative nucleic acid and positive doxorubicin. In this review, we firstly summarized the synthetic methods of amphiphilic copolymers PEG-polypeptide, and emphatically discussed recent progress on their applications as nanocarriers for therapeutic agents from following aspects: PEG-nonionic polypeptide copolymer micelles, PEG-anionic polypeptide micelles, and PEGcationic polypeptide micelles. PMID:26696015

  15. Diketopyrrolopyrrole-based Conjugated Polymers Bearing Branched Oligo(Ethylene Glycol) Side Chains for Photovoltaic Devices.


    Chen, Xingxing; Zhang, Zijian; Ding, Zicheng; Liu, Jun; Wang, Lixiang


    Conjugated polymers are essential for solution-processable organic opto-electronic devices. In contrast to the great efforts on developing new conjugated polymer backbones, research on developing side chains is rare. Herein, we report branched oligo(ethylene glycol) (OEG) as side chains of conjugated polymers. Compared with typical alkyl side chains, branched OEG side chains endowed the resulting conjugated polymers with a smaller π-π stacking distance, higher hole mobility, smaller optical band gap, higher dielectric constant, and larger surface energy. Moreover, the conjugated polymers with branched OEG side chains exhibited outstanding photovoltaic performance in polymer solar cells. A power conversion efficiency of 5.37 % with near-infrared photoresponse was demonstrated and the device performance could be insensitive to the active layer thickness. PMID:27258171

  16. Protein partitioning in poly(ethylene glycol)/sodium polyacrylate aqueous two-phase systems.


    Johansson, Hans-Olof; Magaldi, Flavio Musa; Feitosa, Eloi; Pessoa, Adalberto


    The partition of hemoglobin, lysozyme and glucose-6-phosphate dehydrogenase (G6PDH) in a novel inexpensive aqueous two-phase system (ATPS) composed by poly(ethylene glycol) (PEG) and sodium polyacrylate (NaPA) has been studied. The effect of NaCl and Na(2)SO(4), pH and PEG molecular size on the partitioning has been studied. At high pH (above 9), hemoglobin partitions strongly to the PEG-phase. Although some precipitation of hemoglobin occurs, high recovery values are obtained particularly for lysozyme and G6PDH. The partitioning forces are dominated by the hydrophobic and electrochemical (salt) effects, since the positively charged lysozyme and negatively charged G6PDH partitions to the non-charged PEG and the strongly negatively charged polyacrylate enriched phase, respectively. PMID:18078945

  17. Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids

    SciTech Connect

    Jha, Neetu; Ramaprabhu, S.


    High thermal conducting metal nanoparticles have been dispersed on the multiwalled carbon nanotubes (MWNTs) outer surface. Structural and morphological characterizations of metal dispersed MWNTs have been carried out using x-ray diffraction analysis, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy. Nanofluids have been synthesized using metal-MWNTs in de-ionized water (DI water) and ethylene glycol (EG) base fluids. It has been observed that nanofluids maintain the same sequence of thermal conductivity as that of metal nanoparticles Ag-MWNTs>Au-MWNTs>Pd-MWNTs. A maximum enhancement of 37.3% and 11.3% in thermal conductivity has been obtained in Ag-MWNTs nanofluid with DI water and EG as base fluids, respectively, at a volume fraction of 0.03%. Temperature dependence study also shows enhancement of thermal conductivity with temperature.

  18. Conformation and Phase Separation of Oligo (ethylene glycol) Grafted Polystyrene in Dilute Aqueous Solutions

    SciTech Connect

    Cheng, Gang; Melnichenko, Yuri B; Wignall, George D; Hua, Fengjun; Hong, Kunlun; Mays, Jimmy


    Temperature induced conformational changes of poly(p-oligo(ethylene glycol) styrene) (POEGS) in aqueous solutions were investigated by small angle neutron scattering (SANS), neutron transmission and dynamic light scattering (DLS). The molecular weight of the polymer studied was 9400 g/mol with a polydispersity index of 1.18 and each repeat unit of the polymer had four ethylene glycol monomer segments. The polymer was water soluble due to the hydrophilicity of the OEG side chains and these solutions showed lower critical solution temperature (LCST) depending on the concentration of the polymer. Measurements of solution behavior were made as a function of temperature in the range of 25-55 C for three polymer concentrations (0.1 wt%, 0.3 wt%, and 1.8 wt%). Neutron transmission measurements were used to monitor the amount of polymer which precipitated or remained in solution above the cloud point temperature (T{sub CP}). DLS revealed the presence of large clusters in all solutions both below and above T{sub CP} while SANS provided information on the structure and interactions between individual chains. It was found that in the homogeneous region below T{sub CP} the shape of individual polymers in solution was close to ellipsoidal with the dimensions R{sub a} = 37 Angstroms and R{sub b} = 14 Angstroms and was virtually independent of temperature. The SANS data taken for the most concentrated solution studied (1.8 wt%) were fit to the ellipsoidal model with attractive interactions which were approximated by the Ornstein-Zernike function with a temperature-dependent correlation length in the range of 24-49 Angstroms. The collapse of individual polymers to spherical globules with the radius of 15 Angstroms above TCP was observed.

  19. Intentional Ethylene Glycol Poisoning Increase after Media Coverage of Antifreeze Murders

    PubMed Central

    Morgan, Brent W.; Geller, Robert J.; Kazzi, Ziad N.


    Background: The media can have a profound impact on human behavior. A sensational murder by ethylene glycol (EG) poisoning occurred in our state. The regional media provided extensive coverage of the murder. We undertook this investigation to evaluate our incidence of EG poisoning during the timeframe of before the first report linking a death to ethylene glycol to shortly after the first murder trial. Methods: Descriptive statistics and linear regression were used to describe and analyze the number of EG cases over time. A search of the leading regional newspaper’s archives established the media coverage timeline. Result: Between 2000 and 2004, our poison center (PC) handled a steady volume of unintentional exposures to EG [range: 105–123 per year, standard deviation (SD)=7.22]. EG exposures thought to be suicidal in intent increased from 12 cases in 2000 to 121 cases in 2004. In the 19 months prior to the first media report of this story, our PC handled a mean of 1 EG case with suicidal intent per month [range: 0–2, SD=.69]. In the month after the first media report, our PC handled 5 EG cases with suicidal intent. When media coverage was most intense (2004), our PC received a mean of 10 EG suicidal-intent calls per month [range: 5–17, SD=3.55]. Although uncommon, reports of malicious EG poisonings also increased during this same period from 2 in 2000 to 14 in 2004. Conclusion: Media coverage of stories involving poisonings may result in copycat events, applicable to both self-poisonings and concern for malicious poisonings. Poison centers should be aware of this phenomenon, pay attention to local media and plan accordingly if a poisoning event receives significant media coverage. The media should be more sensitive to the content of their coverage and avoid providing “how to” poisoning information. PMID:21731785

  20. The role of serum proteins in Staphylococcus aureus adhesion to ethylene glycol coated surfaces.


    Schuster, Swen; Yu, Wenqi; Nega, Mulugeta; Chu, Ya-Yun; Zorn, Stefan; Zhang, Fajun; Götz, Friedrich; Schreiber, Frank


    Bacterial adhesion on implants is a first step in the development of chronic foreign body associated infections. Finding strategies to minimize bacterial adhesion may contribute to minimize such infections. It is known that surfaces with oligo-ethylene-glycol (EG3OMe) or poly-ethylene-glycol (PEG2k) terminations decrease unspecific protein adsorption and bacterial adhesion. However, little is known about the influence of serum and its components on bacterial adhesion. We therefore prepared two coatings on gold surface with HS-(CH2)11EG3OMe (EG3OMe) and PEG2k-thiol and studied the role of bovine serum albumin (BSA), γ-globulins, and serum on Staphylococcus aureus adhesion. While BSA and lysozyme showed no adherence even when applied at very high concentrations (100 mg/ml), γ-globulins adsorbed already from 10 mg/ml on. The adsorption of γ-globulins was, however, significantly decreased when it was mixed with BSA in a ratio of 3:1, as it is in the serum. Pretreatment of EG3OMe and PEG2k coatings with γ-globulins or serum strongly promoted adherence of S. aureus when resuspended in buffer, suggesting that γ-globulins play a pivotal role in promoting S. aureus adhesion by its IgG binding proteins; the finding that a spa-deletion mutant, lacking the IgG binding protein A, showed decreased adherence corroborated this. Similarly, when S. aureus was pretreated with serum or γ-globulins its adherence was also significantly decreased. Our findings show that particularly γ-globulins bind to the coated surfaces thus mediating adherence of S. aureus via its protein A. As pretreatment of S. aureus with serum or γ-globulins significantly decreased adherence, treatment of patients with γ-globulins before implant surgery might lower the risk of implant-associated infections. PMID:24980510

  1. Weak intramolecular interaction effects on the torsional spectra of ethylene glycol, an astrophysical species

    NASA Astrophysics Data System (ADS)

    Boussessi, R.; Senent, M. L.; Jaïdane, N.


    An elaborate variational procedure of reduced dimensionality based on explicitly correlated coupled clusters calculations is applied to understand the far infrared spectrum of ethylene-glycol, an astrophysical species. This molecule can be classified in the double molecular symmetry group G8 and displays nine stable conformers, gauche and trans. In the gauche region, the effect of the potential energy surface anisotropy due to the formation of intramolecular hydrogen bonds is relevant. For the primary conformer, stabilized by a hydrogen bond, the ground vibrational state rotational constants are computed to be A0 = 15 369.57 MHz, B0 = 5579.87 MHz, and C0 = 4610.02 MHz corresponding to differences of 6.3 MHz, 7.2 MHz, and 3.5 MHz from the experimental parameters. Ethylene glycol displays very low torsional energy levels whose classification is not straightforward and requires a detailed analysis of the torsional wavefunctions. Tunneling splittings are significant and unpredictable due to the anisotropy of the potential energy surface PES. The ground vibrational state splits into 16 sublevels separated ˜142 cm-1. The splitting of the "G1 sublevels" was calculated to be ˜0.26 cm-1 in very good agreement with the experimental data (0.2 cm-1 = 6.95 MHz). Transitions corresponding to the three internal rotation modes allow assignment of previously observed Q branches. Band patterns, calculated between 362.3 cm-1 and 375.2 cm-1, 504 cm-1 and 517 cm-1, and 223.3 cm-1 and 224.1 cm-1, that correspond to the tunnelling components of the v21 fundamental (v21 = OH-torsional mode), are assigned to the prominent experimental Q branches.

  2. Hepatocyte-targeting gene transfer mediated by galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative

    PubMed Central

    Wang, Yuqiang; Su, Jing; Cai, Wenwei; Lu, Ping; Yuan, Lifen; Jin, Tuo; Chen, Shuyan; Sheng, Jing


    Biscarbamate cross-linked polyethylenimine derivative (PEI-Et) has been reported as a novel nonviral vector for efficient and safe gene transfer in our previous work. However, it had no cell-specificity. To achieve specific delivery of genes to hepatocytes, galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative (GPE) was prepared through modification of PEI-Et with poly(ethylene glycol) and lactobionic acid, bearing a galactose group as a hepatocyte-targeting moiety. The composition of GPE was characterized by proton nuclear magnetic resonance. The weight-average molecular weight of GPE measured with a gel permeation chromatography instrument was 9489 Da, with a polydispersity of 1.44. GPE could effectively condense plasmid DNA (pDNA) into nanoparticles. Gel retardation assay showed that GPE/pDNA complexes were completely formed at weigh ratios (w/w) over 3. The particle size of GPE/pDNA complexes was 79–100 nm and zeta potential was 6–15 mV, values which were appropriate for cellular uptake. The morphology of GPE/pDNA complexes under atomic force microscopy appeared spherical and uniform in size, with diameters of 53–65 nm. GPE displayed much higher transfection efficiency than commercially available PEI 25 kDa in BRL-3A cell lines. Importantly, GPE showed good hepatocyte specificity. Also, the polymer exhibited significantly lower cytotoxicity compared to PEI 25 kDa at the same concentration or weight ratio in BRL-3A cell lines. To sum up, our results indicated that GPE might carry great potential in safe and efficient hepatocyte-targeting gene delivery. PMID:23576866

  3. Hepatocyte-targeting gene transfer mediated by galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative.


    Wang, Yuqiang; Su, Jing; Cai, Wenwei; Lu, Ping; Yuan, Lifen; Jin, Tuo; Chen, Shuyan; Sheng, Jing


    Biscarbamate cross-linked polyethylenimine derivative (PEI-Et) has been reported as a novel nonviral vector for efficient and safe gene transfer in our previous work. However, it had no cell-specificity. To achieve specific delivery of genes to hepatocytes, galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative (GPE) was prepared through modification of PEI-Et with poly(ethylene glycol) and lactobionic acid, bearing a galactose group as a hepatocyte-targeting moiety. The composition of GPE was characterized by proton nuclear magnetic resonance. The weight-average molecular weight of GPE measured with a gel permeation chromatography instrument was 9489 Da, with a polydispersity of 1.44. GPE could effectively condense plasmid DNA (pDNA) into nanoparticles. Gel retardation assay showed that GPE/pDNA complexes were completely formed at weigh ratios (w/w) over 3. The particle size of GPE/pDNA complexes was 79-100 nm and zeta potential was 6-15 mV, values which were appropriate for cellular uptake. The morphology of GPE/pDNA complexes under atomic force microscopy appeared spherical and uniform in size, with diameters of 53-65 nm. GPE displayed much higher transfection efficiency than commercially available PEI 25 kDa in BRL-3A cell lines. Importantly, GPE showed good hepatocyte specificity. Also, the polymer exhibited significantly lower cytotoxicity compared to PEI 25 kDa at the same concentration or weight ratio in BRL-3A cell lines. To sum up, our results indicated that GPE might carry great potential in safe and efficient hepatocyte-targeting gene delivery. PMID:23576866

  4. CO2 Fixation into Novel CO2 Storage Materials Composed of 1,2-Ethanediamine and Ethylene Glycol Derivatives.


    Zhao, Tianxiang; Guo, Bo; Han, Limin; Zhu, Ning; Gao, Fei; Li, Qiang; Li, Lihua; Zhang, Jianbin


    A new CO2 fixation process into solid CO2 -storage materials (CO2 SMs) under mild conditions has been developed. The novel application of amine-glycol systems to the capture, storage, and utilization of CO2 with readily available 1,2-ethanediamine (EDA) and ethylene glycol derivatives (EGs) was demonstrated. Typically, the CO2 SMs were isolated in 28.9-47.5 % yields, followed by extensive characterization using (13) C NMR, XRD, and FTIR. We found that especially the resulting poly-ethylene-glycol-300-based CO2 SM (PCO2 SM) product could be processed into stable tablets for CO2 storage; the aqueous PCO2 SM solution exhibited remarkable CO2 capturing and releasing capabilities after multiple cycles. Most importantly, the EDA and PEG 300 released from PCO2 SM were found to act as facilitative surfactants for the multiple preparation of CaCO3 microparticles with nano-layer structure. PMID:25952008

  5. Surface modification of poly(styrene-b-(ethylene-co-butylene)-b-styrene) elastomer via photo-initiated graft polymerization of poly(ethylene glycol)

    NASA Astrophysics Data System (ADS)

    Li, Xiaomeng; Luan, Shifang; Yang, Huawei; Shi, Hengchong; Zhao, Jie; Jin, Jing; Yin, Jinghua; Stagnaro, Paola


    Poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) copolymer biomedical elastomer was covalently grafted with poly(ethylene glycol) methyl ether methacrylate (PEGMA) via a photo-initiated graft polymerization technique. The surface graft polymerization of SEBS with PEGMA was verified by ATR-FTIR and XPS. Effect of graft polymerization parameters, i.e., monomer concentration, UV irradiation time and initiator concentration on the grafting density was investigated. Comparing with the virgin SEBS film, the PEGMA-modified SEBS film presented an enhanced wettability and a larger surface energy. Besides, the surface grafting of PEGMA imparted excellent anti-platelet adhesion and anti-protein adsorption to the SEBS surface.

  6. Assessing the toxic effects of ethylene glycol ethers using Quantitative Structure Toxicity Relationship models

    SciTech Connect

    Ruiz, Patricia; Mumtaz, Moiz; Gombar, Vijay


    Experimental determination of toxicity profiles consumes a great deal of time, money, and other resources. Consequently, businesses, societies, and regulators strive for reliable alternatives such as Quantitative Structure Toxicity Relationship (QSTR) models to fill gaps in toxicity profiles of compounds of concern to human health. The use of glycol ethers and their health effects have recently attracted the attention of international organizations such as the World Health Organization (WHO). The board members of Concise International Chemical Assessment Documents (CICAD) recently identified inadequate testing as well as gaps in toxicity profiles of ethylene glycol mono-n-alkyl ethers (EGEs). The CICAD board requested the ATSDR Computational Toxicology and Methods Development Laboratory to conduct QSTR assessments of certain specific toxicity endpoints for these chemicals. In order to evaluate the potential health effects of EGEs, CICAD proposed a critical QSTR analysis of the mutagenicity, carcinogenicity, and developmental effects of EGEs and other selected chemicals. We report here results of the application of QSTRs to assess rodent carcinogenicity, mutagenicity, and developmental toxicity of four EGEs: 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol and their metabolites. Neither mutagenicity nor carcinogenicity is indicated for the parent compounds, but these compounds are predicted to be developmental toxicants. The predicted toxicity effects were subjected to reverse QSTR (rQSTR) analysis to identify structural attributes that may be the main drivers of the developmental toxicity potential of these compounds.

  7. Controlling microencapsulation and release of micronized proteins using poly(ethylene glycol) and electrospraying.


    Bock, Nathalie; Dargaville, Tim R; Woodruff, Maria A


    The fabrication of tailored microparticles for delivery of therapeutics is a challenge relying upon a complex interplay between processing parameters and materials properties. The emerging use of electrospraying allows better tailoring of particle morphologies and sizes than current techniques, critical to reproducible release profiles. While dry encapsulation of proteins is essential for the release of active therapeutics from microparticles, it is currently uncharacterized in electrospraying. To this end, poly(ethylene glycol) (PEG) was assessed as a micronizing and solubilizing agent for dry protein encapsulation and release from electrosprayed particles made from polycaprolactone (PCL). The physical effect of PEG in protein-loaded poly(lactic-co-glycolic acid) (PLGA) particles was also studied, for comparison. The addition of 5-15 wt% PEG 6 kDa or 35 kDa resulted in reduced PCL particle sizes and broadened distributions, which could be improved by tailoring the electrospraying processing parameters, namely by reducing polymer concentration and increasing flow rate. Upon micronization, protein particle size was reduced to the micrometer domain, resulting in homogenous encapsulation in electrosprayed PCL microparticles. Microparticle size distributions were shown to be the most determinant factor for protein release by diffusion and allowed specific control of release patterns. PMID:24657821

  8. Incorporation of Therapeutic Interventions in Physiologically Based Pharmacokinetic Modeling of Human Clinical Case Reports of Accidental or Intentional Overdosing with Ethylene Glycol

    SciTech Connect

    Corley, Rick A.; McMartin, K. E.


    Ethylene glycol is a high production volume chemical used in the manufacture of resins and fibers, antifreeze, deicing fluids, heat transfer and hydraulic fluids. Although occupational uses of ethylene glycol have not been associated with adverse effects, there are case reports where humans have either intentionally or accidentally ingested large quantities of ethylene glycol, primarily from antifreeze. The acute toxicity of ethylene glycol in humans and animals and can proceed through three stages, each associated with a different metabolite: central nervous system depression (ethylene glycol), cardiopulmonary effects associated with metabolic acidosis (glycolic acid) and ultimately renal toxicity (oxalic acid), depending upon the total amounts consumed and effectiveness of therapeutic interventions. A physiologically based pharmacokinetic (PBPK) model developed in a companion paper (Corley et al., 2004) was refined in this study to include clinically relevant treatment regimens for ethylene glycol poisoning such as hemodialysis or metabolic inhibition with either ethanol or fomepizole. Such modifications enabled the model to describe several human case reports which included analysis of ethylene glycol and/or glycolic acid. Such data and model simulations provide important confirmation that the PBPK model developed previously can adequately describe the pharmacokinetics of ethylene glycol in humans following low, occupational or environmentally relevant inhalation exposures, as well as massive oral doses even under conditions where treatments have been employed that markedly affect the disposition of ethylene glycol and glycolic acid. By integrating the case report data sets with controlled studies in this PBPK model, it was demonstrated that fomepizole, if administered early enough in a clinical situation, can be more effective than ethanol or hemodialysis in preventing the metabolism of ethylene glycol to more toxic metabolites. Hemodialysis remains an

  9. Determination of trace amounts of ethylene glycol and its analogs in water matrixes by liquid chromatography/tandem mass spectrometry.


    Tran, Buu N; Okoniewski, Richard; Bucciferro, Anthony; Jansing, Robert; Aldous, Kenneth M


    Contamination of drinking water by ethylene glycol (EG) is a public health concern. EG causes adverse health effects in humans and animals, including cardiopulmonary and acute renal failure. EG and other glycols, such as propylene glycol (PG) are major components in antifreeze liquids, which may be the main source of contamination of ground water. A sensitive LC/electrospray ionization (ESI)-MS/MS method was developed to measure trace amounts of EG, diethylene glycol, and 1,2- and 1,3-PG in several water sources, including municipal tap, lake, river, and salinated water. In this method, glycols in water samples were derivatized with benzoyl chloride by the Schotten-Baumann reaction, followed by liquid-liquid extraction using pentane as the organic solvent prior to the LC/ESI-MS/MS determination. QC included analysis of a method blank and samples fortified at low and high levels. Analytical data showed excellent linear calibration for all observed glycols, with good precision and accuracy. The method detection limits for the studied glycols ranged from 1.9 to 6.1 ng/mL across the water matrixes tested. This method is suitable to help assess water quality in areas that may be prone to glycol contamination. PMID:24672883

  10. The characterization of dendronized poly(ethylene glycol)s and poly(ethylene glycol) multi-arm stars using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.


    Myers, Brittany K; Zhang, Boyu; Lapucha, Joanna E; Grayson, Scott M


    The synthesis of branched poly(ethylene glycol) (PEG) derivatives, namely star PEG and dendronized PEG, can be challenging and their purity can be difficult to ascertain using traditional techniques, such as NMR and GPC. Herein, the detailed characterization of these branched PEGs using MALDI-ToF MS was investigated in order to confirm their structural purity. In this light, mass spectrometry offers a number of advantages for polymer characterization, including the ability to get detailed structural data, such as end group masses, from microgram-scale samples. In addition, the ability to rapidly acquire data from crude reaction aliquots makes MALDI-ToF MS ideal for monitoring end group transformations. PMID:24370103

  11. Subchronic toxicity of ethylene glycol in Wistar and F-344 rats is related to metabolism and clearance of metabolites.

    SciTech Connect

    Cruzan, G; Corley, Rick A.; Hard, G; Mertens, J W.; McMartin, K. E.; Snellings, W; Gingell, Ralph; Deyo, J A.


    Ethylene Glycol (CAS RN 107-21-1) can to cause kidney toxicity via the formation of calcium oxalate crystals in a variety of species including humans. Numerous repeated dose studies conducted in rats have indicated that male rats are more susceptible than female rats. Furthermore, subchronic and chronic studies using different dietary exposure regimens have indicated that male Wistar rats may be more sensitive to renal toxicity than male F344 rats. This study was, therefore, conducted to compare the toxicity of ethylene glycol in the two strains of rats under identical exposure conditions and to evaluate the potential contribution of toxicokinetic differences to strain sensitivity. Ethylene glycol was mixed in the diet at concentrations to deliver constant target dosage levels of 0, 50, 150, 500, or 1000 mg/kg/day for 16 weeks to groups of 10 male Wistar and 10 male F-344 rats based upon weekly group mean body weights and feed consumption. Kidneys were examined histologically for calcium oxalate crystals and pathology. Samples of blood, urine and kidneys from satellite animals exposed to 0, 150, 500, or 1000 mg/kg/day for 1 or 16 weeks were analyzed for ethylene glycol, glycolic acid and oxalic acid. Treatment of Wistar rats at 1000 mg/kg/day resulted in the death of 2 rats; in addition, at 500 and 1000 mg/kg/day, group mean body weights were decreased compared to control throughout the 16 weeks. In F-344 rats exposed at 1000 mg/kg/day and in Wistar rats at 500 and 1000 mg/kg/day, there were lower urine specific gravities, higher urine volumes, and increased absolute and relative kidney weights. In both strains of rats treated at 500 and 1000 mg/kg/day, some or all treated animals had increased calcium oxalate crystals in the kidney tubules and crystal nephropathy. The effect was more severe in Wistar rats than in F-344 rats. Accumulation of oxalic acid in the kidneys of both strains of rats were consistent with the dose- and strain-dependent toxicity. As the

  12. Immobilization of enzyme onto poly(ethylene-vinyl alcohol) membrane

    SciTech Connect

    Imai, K.; Shiomi, T.; Uchida, K.; Miya, M.


    Invertase was ionically bound to the poly(ethylene-vinyl alcohol) membrane surface modified with two aminoacetals with different molecular length, 2-dimethyl-aminoacetoaldehyde dimethylacetal (AAA) and 3-(N,N-dimethylamino-n-propanediamine) propionaldehyde dimethylacetal (APA). Immobilization conditions were determined with respect to enzyme concentration in solution, pH value, ionic strength in immobilization solution, and immobilization time. Various properties of immobilized invertase were evaluated, and thermal stability was found especially to be improved by immobilization. The apparent Michaelis constant, Km, was smaller for invertase bound by APA with longer molecular lengths than for invertase bound by AAA. We attempted to bind glucoamylase of Rhizopus delemarorigin in the same way. The amount and activity of immobilized glucoamylase were much less than those of invertase. 16 references.

  13. The effect of polyethylene glycol on the stability of pores in polyvinyl alcohol hydrogels during annealing.


    Bodugoz-Senturk, Hatice; Choi, Jeeyoung; Oral, Ebru; Kung, Jean H; Macias, Celia E; Braithwaite, Gavin; Muratoglu, Orhun K


    Poly(vinyl alcohol) (PVA) hydrogels are candidate biomaterials for cartilage resurfacing or interpositional arthroplasty devices requiring high-creep resistance and high water content to maintain lubricity. Annealing of PVA improves creep resistance but also reduces the water content. We hypothesized that maintaining poly(ethylene glycol) (PEG) within PVA during annealing would prevent the collapse of the pores and thus would result in high equilibrium water content (EWC). Our hypothesis tested positive. The PVA hydrogels containing PEG maintained their opacity through annealing and exhibited large pores under confocal imaging while hydrogels not containing PEG turned translucent and no pores were visible after annealing. The EWC of gels annealed with PEG (83 +/- 1.0%) was higher than that of the gels processed without PEG (55 +/- 4.8). The crystallinity of the former was 8.0 +/- 1.7% and the latter was 27.5 +/- 8.7%. The hydrogels processed in the presence of PEG exhibited a significantly higher total creep strain (69 +/- 3.4%) when compared to the PEG-free hydrogels (17 +/- 3.7) under an initial contact stress of 0.45 MPa. EWC appeared to be strongly related to the creep resistance of annealed PVA theta-gels. PMID:17950839

  14. Antifouling behaviour of silicon surfaces modified with self-assembled monolayers containing both ethylene glycol and charged moieties

    NASA Astrophysics Data System (ADS)

    Ng, Cheuk Chi Albert; Ciampi, Simone; Harper, Jason B.; Gooding, J. Justin


    Herein reported is the synthesis of functionalised oligoethylene glycol molecules, with an azido group at one end and an ionisable group at the other end, and their attachment onto alkyne-terminated silicon(100) surfaces using 'click' chemistry. The modified surfaces were characterised using X-ray photoelectron spectroscopy (XPS) and water contact angle goniometry. The antifouling behaviour of these surfaces was assessed and it was shown that while surfaces presenting both charged and ethylene glycol moieties are antifouling, the antifouling effectiveness is influenced by the surface charge as modulated via the pH of the solution.

  15. Steam Reforming of Ethylene Glycol over MgAl₂O₄ Supported Rh, Ni, and Co Catalysts

    SciTech Connect

    Mei, Donghai; Lebarbier, Vanessa M.; Xing, Rong; Albrecht, Karl O.; Dagle, Robert A.


    Steam reforming of ethylene glycol (EG) over MgAl₂O₄ supported metal (15 wt.% Ni, 5 wt.% Rh, and 15 wt.% Co) catalysts were investigated using combined experimental and theoretical methods. Compared to highly active Rh and Ni catalysts with 100% conversion, the steam reforming activity of EG over the Co catalyst is comparatively lower with only 42% conversion under the same reaction conditions (500°C, 1 atm, 119,000 h⁻¹, S/C=3.3 mol). However, CH₄ selectivity over the Co catalyst is remarkably lower. For example, by varying the gas hour space velocity (GHSV) such that complete conversion is achieved for all the catalysts, CH₄ selectivity for the Co catalyst is only 8%, which is much lower than the equilibrium CH₄ selectivity of ~ 24% obtained for both the Rh and Ni catalysts. Further studies show that varying H₂O concentration over the Co catalyst has a negligible effect on activity, thus indicating zero-order dependence on H₂O. These experimental results suggest that the supported Co catalyst is a promising EG steam reforming catalyst for high hydrogen production. To gain mechanistic insight for rationalizing the lower CH₃ selectivity observed for the Co catalyst, the initial decomposition reaction steps of ethylene glycol via C-O, O-H, C-H, and C-C bond scissions on the Rh(111), Ni(111) and Co(0001) surfaces were investigated using density functional theory (DFT) calculations. Despite the fact that the bond scission sequence in the EG decomposition on the three metal surfaces varies, which leads to different reaction intermediates, the lower CH₄ selectivity over the Co catalyst, as compared to the Rh and Ni catalysts, is primarily due to the higher barrier for CH₄ formation. The higher S/C ratio enhances the Co catalyst stability, which can be elucidated by the facile water dissociation and an alternative reaction path to remove the CH species as a coking precursor via the HCOH formation. This work was financially supported by the United

  16. Engineering oligo(ethylene glycol) based nonfouling surfaces and microstructures for biomedical applications

    NASA Astrophysics Data System (ADS)

    Ma, Hongwei

    This thesis presents the initial development of oligo(ethylene glycol) (OEG) based "nonfouling"---protein and cell resistant---coatings that can be applied to a wide range of biomedical applications. The hypothesis underlying this work is that a high density of OEG will eliminate nonspecific protein adsorption thus reduce or eradicate undesired surface phenomena, such as poor biocompatibility, which are direct consequences of the nonspecific protein adsorption. A generalized method for creating functionalized nonfouling surfaces was developed by combining two strategies, namely "Surface-Initiated Atom Transfer Radical Polymerization of Oligo(ethylene glycol) methyl methacrylate (SI-ATRP of OEGMA)" and "Modular design of initiator", demonstrated on gold (metallic materials), glass and silicon oxide (hydroxylated substrates). SI-ATRP was able to achieve an OEG coating with a density higher than all the pre-existing techniques could achieve. It also provided control over the coating thickness and architecture that are not easily controlled by other techniques. Thickness-density profile of poly(OEGMA) was constructed based on SI-ATRP from mixed SAMs on gold. For the first time, we constructed a map of protein resistance of PEG coated surfaces, which reveals the relationship between the poly(OEGMA) coatings and their protein adsorption. Besides its scientific implications, the practical use (from an engineering point of view) of these results is that the information shall be instructive in designing nonfouling surfaces by providing critical structural parameters. This thesis also demonstrates integration of SI-ATRP with micro and nano scale pattern fabrication, which further expands the applications of this technology. In vitro cell culturing on patterned surfaces confirmed that high-density OEG coatings were exceptionally nonfouling even in physiological milieu, which shows great promise for the in vivo study of OEG coatings. A prototype protein microarray was

  17. Synthesis, characterization and cytotoxicity of poly(ethylene glycol)-graft-trimethyl chitosan block copolymers.


    Mao, Shirui; Shuai, Xintao; Unger, Florian; Wittmar, Matthias; Xie, Xiulan; Kissel, Thomas


    PEGylated trimethyl chitosan (TMC) copolymers were synthesized in an attempt to both increase the solubility of chitosan in water, and improve the biocompatibility of TMC. A series of copolymers with different degrees of substitution were obtained by grafting activated poly(ethylene glycol)s (PEG) of different MW onto TMC via primary amino groups. Structure of the copolymers was characterized using 1H, 13C NMR spectroscopy and GPC. Solubility experiments demonstrated that PEG-g-TMC copolymers were completely water-soluble over the entire pH range of 1-14 regardless of the PEG MW, even when the graft density was as low as 10%. Using the methyl tetrazolium (MTT) assay, the effect of TMC molecular weight, PEGylation ratio, PEG and TMC molecular weight in the copolymers, and complexation with insulin on the cytotoxicity of TMC was examined, and IC50 values were calculated with L929 cell line. All polymers exhibited a time- and dose-dependent cytotoxic response that increased with molecular weight. PEGylation can decrease the cytotoxicity of TMC to a great extent in the case of low molecular weight TMCs. According to the cytotoxicity results, PEG 5 kDa is superior for PEGylation when compared to PEG 550 Da at similar graft ratios. Complexation with insulin further increased cell viability. In addition, Lactate dehydrogenase (LDH) assays were performed to quantify the membrane-damaging effects of the copolymers, which is in line with the conclusion drawn from MTT assay. Moreover, the safety of the copolymers was corroborated by observing the morphological change of the cells with inverted phase contrast microscopy. Based upon these results PEG-g-TMC merits further investigations as a drug delivery vehicle. PMID:15913769

  18. Design and synthesis of multifunctional poly(ethylene glycol)s using enzymatic catalysis for multivalent cancer drug delivery

    NASA Astrophysics Data System (ADS)

    Seo, Kwang Su

    The objective of this research was to design and synthesize multifunctional poly(ethylene glycol)s (PEG)s using enzyme-catalyzed reactions for multivalent targeted drug delivery. Based on computer simulation for optimum folate binding, a four-arm PEG star topology with Mn = 1000 g/mol was proposed. First, a four-functional core based on tetraethylene glycol (TEG) was designed and synthesized using transesterification and Michael addition reactions in the presence of Candida antarctica lipase B (CALB) as a biocatalyst. The four-functional core (HO)2-TEG-(OH)2 core was successfully prepared by the CALB-catalyzed transesterification of vinyl acrylate (VA) with TEG and then Michael addition of diethanolamine to the resulting TEG diacrylate with/without the use of solvent. The functional PEG arms with fluorescein isothiocyanate (FITC) and folic acid (FA) were prepared using both traditional organic chemistry and enzyme-catalyzed reactions. FITC was reacted with the amine group of H2N-PEG-OH in the presence of triethylamine via nucleophilic addition onto the isothiocyanate group. Then, divinyl adipate (DVA) was transesterified with the FITC-PEG-OH product in the presence of CALB to produce the FITC-PEG vinyl ester that will be attached to the four-functional core via CALC-catalyzed transesterification. For the synthesis of FA-PEG vinyl ester arm, DVA was first reacted with PEG-monobenzyl ether (BzPEG-OH) in bulk in the presence of CALB. The BzPEG vinyl ester was then transesterified with 12-bromo-1-dodecanol in the presence of CALB. Finally, BzPEG-Br was attached to FA exclusively in the gamma position using a new method. The thesis also discusses fundamental studies that were carried out in order to get better understanding of enzyme catalyzed transesterification and Michael addition reactions. First, in an effort to investigate the effects of reagent and enzyme concentrations in transesterification, vinyl methacrylate (VMA) was reacted with 2-(hydroxyethyl) acrylate (2

  19. Online Aerosol Mass Spectrometry of Single Micrometer-Sized Particles Containing Poly(ethylene glycol)

    SciTech Connect

    Bogan, M J; Patton, E; Srivastava, A; Martin, S; Fergenson, D; Steele, P; Tobias, H; Gard, E; Frank, M


    Analysis of poly(ethylene glycol)(PEG)-containing particles by online single particle aerosol mass spectrometers equipped with laser desorption ionization (LDI) is reported. We demonstrate that PEG-containing particles are useful in the development of aerosol mass spectrometers because of their ease of preparation, low cost, and inherently recognizable mass spectra. Solutions containing millimolar quantities of PEGs were nebulized and, after drying, the resultant micrometer-sized PEG containing particles were sampled. LDI (266 nm) of particles containing NaCl and PEG molecules of average molecular weight <500 generated mass spectra reminiscent of mass spectra of PEG collected by other MS schemes including the characteristic distribution of positive ions (Na{sup +} adducts) separated by the 44 Da of the ethylene oxide units separating each degree of polymerization. PEGs of average molecular weight >500 were detected from particles that also contained t the tripeptide tyrosine-tyrosine-tyrosine or 2,5-dihydroxybenzoic acid, which were added to nebulized solutions to act as matrices to assist LDI using pulsed 266 nm and 355 nm lasers, respectively. Experiments were performed on two aerosol mass spectrometers, one reflectron and one linear, that each utilize two time-of-flight mass analyzers to detect positive and negative ions created from a single particle. PEG-containing particles are currently being employed in the optimization of our bioaerosol mass spectrometers for the application of measurements of complex biological samples, including human effluents, and we recommend that the same strategies will be of great utility to the development of any online aerosol LDI mass spectrometer platform.

  20. Extraction of americium in different oxidation states in a two-phase aqueous system based on poly(ethylene glycol)

    SciTech Connect

    Molochnikova, N.P.; Frenkel', B.F.; Myasoedov, B.F.; Shkinev, V.M.; Spivakov, B.Ya.; Zolotov, Yu.A.


    The extraction of americium in different states of oxidation was studied in a two-phase aqueous system based on poly(ethylene glycol). Conditions were found for the quantitative extraction of americium (III) and americium (V) from solutions of ammonium sulfate in the pH range of 3-5 and in the presence of arsenazo III. The composition of the complexes of americium with the reagent was determined; americium (III) reacts with arsenazo III in solutions of ammonium sulfate to form complexes with the composition of MeR and Me/sub 2/R. Characteristics of the absorption spectra of complexes of americium (III) and (V) with arsenazo III in ammonium sulfate solutions and in extracts based on aqueous solutions of poly(ethylene glycol) were found. The molar extinction coefficients of complexes of americium with arsenazo III were determined in these solutions.

  1. Performance of AA5052 alloy anode in alkaline ethylene glycol electrolyte with dicarboxylic acids additives for aluminium-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, DaPeng; Zhang, DaQuan; Lee, KangYong; Gao, LiXin


    Dicarboxylic acid compounds, i.e. succinic acid (SUA), adipic acid (ADA) and sebacic acid (SEA), are used as electrolyte additives in the alkaline ethylene glycol solution for AA5052 aluminium-air batteries. It shows that the addition of dicarboxylic acids lowers the hydrogen gas evolution rate of commercial AA5052 aluminium alloy anode. AA5052 aluminium alloy has wide potential window for electrochemical activity and better discharge performance in alkaline ethylene glycol solution containing dicarboxylic acid additives. ADA has the best inhibition effect for the self-corrosion of AA5052 anode among the three dicarboxylic acid additives. Fourier transform infrared spectroscopy (FT-IR) reveals that dicarboxylic acids and aluminium ions can form coordination complexes. Quantum chemical calculations shows that ADA has a smaller energy gap (ΔE, the energy difference between the lowest unoccupied orbital and the highest occupied orbital), indicating that ADA has the strongest interaction with aluminium ions.

  2. Lysozyme-coupled poly(poly(ethylene glycol) methacrylate)-stainless steel hybrids and their antifouling and antibacterial surfaces.


    Yuan, Shaojun; Wan, Dong; Liang, Bin; Pehkonen, S O; Ting, Y P; Neoh, K G; Kang, E T


    An environmentally benign approach to impart stainless steel (SS) surfaces with antifouling and antibacterial functionalities was described. Surface-initiated atom transfer radical polymerization (ATRP) of poly(ethylene glycol) monomethacrylate) (PEGMA) from the SS surface-coupled catecholic L-3,4-dihydroxyphenylalanine (DOPA) with terminal alkyl halide initiator was first carried out, followed by the immobilization of lysozyme at the chain ends of poly(ethylene glycol) branches of the grafted PEGMA polymer brushes. The functionalized SS surfaces were shown to be effective in preventing bovine serum albumin (BSA) adsorption and in reducing bacterial adhesion and biofilm formation. The surfaces also exhibited good bactericidal effects against Escherichia coli and Staphylococcus aureus. The concomitant incorporation of antifouling hydrophilic brushes and antibacterial enzymes or peptides onto metal surfaces via catecholic anchors should be readily adaptable to other metal substrates, and is potentially useful for biomedical and biomaterial applications. PMID:21338094

  3. Facile synthesis of porous worm-like Pd nanotubes with high electrocatalytic activity and stability towards ethylene glycol oxidation

    NASA Astrophysics Data System (ADS)

    Feng, Jiu-Ju; Zhou, Dan-Ling; Xi, Huan-Xiang; Chen, Jian-Rong; Wang, Ai-Jun


    A facile method was developed for large-scale preparation of porous worm-like Pd nanotubes based on the reduction of PdO nanotubes, which were obtained by calcining the complex precipitate of [Pd(dimethylglyoxime)2]n. The Pd catalyst showed excellent electrocatalytic activity and stability towards ethylene glycol oxidation.A facile method was developed for large-scale preparation of porous worm-like Pd nanotubes based on the reduction of PdO nanotubes, which were obtained by calcining the complex precipitate of [Pd(dimethylglyoxime)2]n. The Pd catalyst showed excellent electrocatalytic activity and stability towards ethylene glycol oxidation. Electronic supplementary information (ESI) available: Experimental section and Fig. S1-S7. See DOI: 10.1039/c3nr01578e

  4. Highly selective and sensitive detection of glutathione using mesoporous silica nanoparticles capped with disulfide-containing oligo(ethylene glycol) chains.


    El Sayed, Sameh; Giménez, Cristina; Aznar, Elena; Martínez-Máñez, Ramón; Sancenón, Félix; Licchelli, Maurizio


    Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo(ethylene glycol) chains were used for the selective and sensitive fluorimetric detection of glutathione. PMID:25482517

  5. Cytocompatible Poly(ethylene glycol)-co-polycarbonate Hydrogels Crosslinked by Copper-free, Strain-promoted “Click” Chemistry

    PubMed Central

    Xu, Jianwen; Filion, Tera M.; Prifti, Fioleda


    Strategies to encapsulate cells in cytocompatible 3-dimensional hydrogels with tunable mechanical properties and degradability without harmful gelling conditions are highly desired for regenerative medicine applications. Here we reported a method for preparing poly(ethylene glycol)-co-polycarbonate hydrogels through copper-free, strain-promoted azide-alkyne cycloaddition (SPAAC) “Click” chemistry. Hydrogels with varying mechanical properties were formed by “clicking” azido-functionalized poly(ethylene glycol)-co-polycarbonate macromers with dibenzocyclooctyne functionalized poly(ethylene glycol) under physiological conditions within minutes. Bone marrow stromal cells encapsulated in these gels exhibited higher cellular viability than those encapsulated in photo-crosslinked poly(ethylene glycol) dimethacrylate. The precise control over the macromer compositions, the cytocompatible SPAAC crosslinking, and the degradability of the polycarbonate segments combined make these hydrogels promising candidates for scaffold- and stem cell-assisted tissue repair and regeneration. PMID:21954076

  6. Near-infrared light-triggered irreversible aggregation of poly(oligo(ethylene glycol) methacrylate)-stabilised polypyrrole nanoparticles under biologically relevant conditions.


    Au, Kin Man; Chen, Mei; Armes, Steven P; Zheng, Nanfeng


    We report the use of near-infrared (NIR) radiation to trigger the irreversible flocculation of poly(oligo(ethylene glycol) methacrylate)-stabilised polypyrrole nanoparticles in physiological buffer. PMID:24089078

  7. Synthesis and characterization of CdSe/ZnS quantum dots conjugated with poly (ethylene glycol) diamine

    NASA Astrophysics Data System (ADS)

    Bharti, Shivani; Kaur, Gurvir; Gupta, Shikha; Tripathi, S. K.


    Bio-functionalization or surface modification is an important technique to obtain biocompatibility in semiconductor nanoparticles for biomedical applications. In this study semiconductor core/shell quantum dots of CdSe/ZnS have been prepared by chemical reduction method and then further PEGylated using Poly(ethylene glycol) diamine of Mw 2000. They were characterized by UV-vis spectroscopy & Fourier transform infrared spectroscopy. The results reveals the successful PEGylation of CdSe/ZnS quantum dots.

  8. Structured Pd-Au/Cu-fiber catalyst for gas-phase hydrogenolysis of dimethyl oxalate to ethylene glycol.


    Zhang, Li; Han, Lupeng; Zhao, Guofeng; Chai, Ruijuan; Zhang, Qiaofei; Liu, Ye; Lu, Yong


    Galvanic co-deposition of 0.5 wt% Au and 0.1 wt% Pd on a microfibrous-structure using 8 μm Cu-fibers delivers a Pd-Au/Cu-fiber catalyst, which is highly active, selective and stable for the hydrogenolysis of dimethyl oxalate to ethylene glycol. Au and Pd synergistically promote the hydrogenolysis activity of Cu(+) sites, while Au also critically stabilizes Cu(+) sites to prevent deep reductive deactivation. PMID:26040855

  9. Synthesis and characterization of CdSe/ZnS quantum dots conjugated with poly (ethylene glycol) diamine

    SciTech Connect

    Bharti, Shivani; Tripathi, S. K.; Kaur, Gurvir; Gupta, Shikha


    Bio-functionalization or surface modification is an important technique to obtain biocompatibility in semiconductor nanoparticles for biomedical applications. In this study semiconductor core/shell quantum dots of CdSe/ZnS have been prepared by chemical reduction method and then further PEGylated using Poly(ethylene glycol) diamine of M{sub w} 2000. They were characterized by UV-vis spectroscopy & Fourier transform infrared spectroscopy. The results reveals the successful PEGylation of CdSe/ZnS quantum dots.

  10. A new synthesis of lamellar-mesostructured silica by using poly(ethylene glycol) distearate as template

    SciTech Connect

    Zhang Huanzhi; Jin Zhengwei; Wang Xiaodong


    A lamellar-mesostructured silica has been synthesized by using poly(ethylene glycol) distearate as template in ethanol solution. Highly ordered lamellar mesostructure was confirmed by X-ray diffraction pattern, transmission electronic microscopy, and nitrogen adsorption-desorption isotherm. The material obtained in this work has a large interlayer distance, and good thermal and mechanical stabilities, which can favor the preparation of the in situ polymerized nanocomposites based on intercalation of polymers in the lamellar-mesostructured silica.