Journal articles: 'Tensioactifs à base de PEG'

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Haldkar, R. K., I. A. Parinov, A. V. Cherpakov, and O. V. Shilyaeva. "Modelling vibrations of axial piezoelectric generator with active base." Journal of Physics: Conference Series 2131, no. 2 (December 1, 2021): 022018. http://dx.doi.org/10.1088/1742-6596/2131/2/022018.

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Abstract Modelling of an axial-type piezoelectric generator (PEG) is considered. PEG is an integral part of the system for converting mechanical vibration energy from the environment into electrical energy. The energy generator has an axial type of the configuration of elements, aimed on using bending and compressive loads simultaneously on piezoelectric elements. The base of the generator is made as an active pinching. A feature of PEG is that the generator has two types of piezoelectric elements: (1) elements located on the substrate in the form of a bimorph and (2) piezoelectric elements of a cylindrical shape, fixing the generator base, located on the same axis. PEG has a symmetrical structure about the center of proof mass. The results of modal and harmonic analysis of vibrations are given for vibration excitation of the PEG base in a certain frequency range. The analysis of the output characteristics is given.

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Ohya, Yuichi, Hidetoshi Kuroda, Keiichi Hirai, and Tatsuro Ouchi. "Synthesis and Cytotoxic Activity of Conjugates of Monomethoxy-Poly(Ethylene Glycol) End-Capped with Doxorubicin via Ester, Amide, or Schiffs Base Bond." Journal of Bioactive and Compatible Polymers 10, no. 1 (January 1995): 51–66. http://dx.doi.org/10.1177/088391159501000106.

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Doxorubicin (adriamycin; ADR) which is one of the most clinically used antitumor agent, has undesirable side-effects. To reduce these side-effects, a macromolecular prodrug of ADR exhibiting high antitumor activity, the conjugate of PEG end-capped with ADR was developed. Tb effect intracellular release of ADR from the conjugate, ester, amide and Schiffs base bonds were employed as modes of bonding ADR to PEG. The MeO-PEG/Schiffs base/ADR conjugate readily released ADR under the lysosomal acidic conditions in vitro and very slowly ADR under physiological conditions. Moreover, the MeO-PEG/Schiffs base/ADR conjugate showed strong cytotoxic activity similar to free ADR against p388D1 lymphocytic leukemia cells in vitro. Fluorescence measurements suggest that the conjugate forms self-aggregates in aqueous solution.

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Leonard, Kaethe N., and Joshua M. Blose. "Effects of osmolytes and macromolecular crowders on stable GAAA tetraloops and their preference for a CG closing base pair." PeerJ 6 (February 13, 2018): e4236. http://dx.doi.org/10.7717/peerj.4236.

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Osmolytes and macromolecular crowders have the potential to influence the stability of secondary structure motifs and alter preferences for conserved nucleic acid sequences in vivo. To further understand the cellular function of RNA we observed the effects of a model osmolyte, polyethylene glycol (PEG) 200, and a model macromolecular crowding agent, PEG 8000, on the GAAA tetraloop motif. GAAA tetraloops are conserved, stable tetraloops, and are critical participants in RNA tertiary structure. They also have a thermodynamic preference for a CG closing base pair. The thermal denaturation of model hairpins containing GAAA loops was monitored using UV-Vis spectroscopy in the presence and absence of PEG 200 or PEG 8000. Both of the cosolutes tested influenced the thermodynamic preference for a CG base pair by destabilizing the loop with a CG closing base pair relative to the loop with a GC closing base pair. This result also extended to a related DNA triloop, which provides further evidence that the interactions between the loop and closing base pair are identical for the d(GCA) triloop and the GAAA tetraloop. Our results suggest that in the presence of model PEG molecules, loops with a GC closing base pair may retain some preferential interactions with the cosolutes that are lost in the presence of the CG closing base pair. These results reveal that relatively small structural changes could influence how neutral cosolutes tune the stability and function of secondary structure motifs in vivo.

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Sesigur, Feyza, Dolunay Sakar, Ozlem Yazici, Fatih Cakar, Ozlem Cankurtaran, and Ferdane Karaman. "Dispersive Surface Energy and Acid-Base Parameters of Tosylate Functionalized Poly(ethylene glycol) via Inverse Gas Chromatography." Journal of Chemistry 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/402325.

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An inverse gas chromatographic (IGC) study of the sorption properties of poly(ethylene glycol) modified with tosylate (PEG-TOS) was presented. PEG-TOS was synthesized via the tosylation of the corresponding poly(ethylene glycol) (PEG) withp-toluenesulfonyl chloride in the basic medium. The synthesized PEG-Tos was characterized by FTIR-ATR and1HNMR techniques. The retention diagrams of n-hexane, n-heptane, n-octane, n-nonane, n-decane, dichloromethane, chloroform, acetone, tetrahydrofuran, ethyl acetate, and ethanol on the PEG and PEG-Tos were plotted at temperatures in K between 303 and 373 by inverse gas chromatography technique. The dispersive component of the surface-free energy,γSD, of studied adsorbent surface was estimated using retention times of different nonpolar organics in the infinite dilution region. Thermodynamic parameters of adsorption (free energy,ΔGAS, enthalpy,ΔHAS, and entropy,ΔSAS), dispersive components of the surface energies,γSD, and the acid,KA, and base,KD, constants for the PEG and PEG-Tos were calculated and the results were discussed.

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Gomes, Cláudio Luís Nina, José Dantas Ribeiro Filho, Rafael Resende Faleiros, Fernanda Timbó D'el Rey Dantas, Lincoln da Silva Amorim, and Waleska de Melo Ferreira Dantas. "Blood gas analysis, anion gap, and strong ion difference in horses treated with polyethylene glycol balanced solution (PEG 3350) or enteral and parenteral electrolyte solutions." Ciência Rural 44, no. 6 (June 2014): 1086–92. http://dx.doi.org/10.1590/s0103-84782014000600022.

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Large volumes of different electrolytes solutions are commonly used for ingesta hydration in horses with large colon impaction, but little is known about their consequences to blood acid-base balance. To evaluate the effects of PEG 3350 or enteral and parenteral electrolyte solutions on the blood gas analysis, anion gap and strong ion difference, five adult female horses were used in a 5x5 latin square design. The animals were divided in five groups and distributed to each of the following treatments: NaCl (0.9% sodium chloride solution); EES (enteral electrolyte solution), EES+LR (EES plus lactated Ringer's solution); PEG (balanced solution with PEG 3350) and PEG+LR (PEG plus lactated Ringer's solution). Treatments PEG or PEG + LR did not change or promoted minimal changes, while the EES caused a slight decrease in pH, but its association with lactated Ringer's solution induced increase in AG and SID values, as well as caused hypernatremia. In turn, the treatment NaCl generated metabolic acidosis. PEG 3350 did not alter the acid-base balance. Despite it's slight acidifying effect, the enteral electrolyte solution (EES) did not cause clinically relevant changes.

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Dewi, Sella_Arbi Nur_Ullya, Dewi Andini_Kunti Mulangsri, and Mufrod Mufrod. "PENGARUH KOMBINASI BASIS PEG 400 DAN BASIS PEG 4000 DALAM FORMULASI SALEP EKSTRAK DAUN SUKUN (Artocarpus altilis) TERHADAP AKTIVITAS ANTIBAKTERINYA." JIFFK : Jurnal Ilmu Farmasi dan Farmasi Klinik 15, no. 2 (December 31, 2018): 13. http://dx.doi.org/10.31942/jiffk.v15i2.2560.

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ABSTRACTBreadfruit leaves contain flavonoid compounds that can inhibit the growth of Staphylococcus aureus bacteria. Breadfruit leaf extract is practical and effective formulated in ointment preparations. The base combination of PEG 400 and PEG 4000 decreases the melting point of PEG 4000, so that it is compatible and can increase the penetration of drugs in the skin. The objective of this study to determine the breadfruit leaf extract ointment with a combination of PEG 400 and PEG 4000 bases as well as antibacterial activity against Staphylococcus aureus bacteria. Breadfruit leaf extract (BLE) was obtained by maceration with 70% ethanol. Salve preparations were made into III formulas with variations in base concentrations of PEG 400 and PEG 4000, namely (F1) 75%: 25%, (F2) 50%: 50%, (F3) 25%: 75%, using the fusion method. Antibacterial activity test used agar well diffusion method. Kruskal Wallis test and Mann Whitney test used for analyzed data from antibacterial activity test. The ointment of Breadfruit leaves extract showed the color of brown ointment, semi-solid form, distinctive aroma of breadfruit leave. All of three ointment formulas have antibacterial activity indicated by the formation of inhibitory zones around the well. All of three ointment formulas have significant differences which means the combination of PEG 400 and PEG 4000 can affect antibacterial activity of BLE ointment. The higher of the concentration PEG 4000 compared PEG 400 caused inhibiton zone become smaller that means the potency of antibacterial decreased. The formula has the greatest antibacterial activity in the FI is 8,02mm.Keywords: breadfruit leaves, ointment, PEG 400 and PEG 4000, antibacterial

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Bireddy, Srinivasa Reddy, Veera Swamy Konkala, and Pramod Kumar Dubey. "A green process PEG‐600 mediated on‐pot, alternative synthesis of 3‐methyl‐2‐(((1‐methyl‐1H‐benzimidazole‐2‐YL) sulfonyl) methyl) quinazolin‐4(3H)‐one." Vietnam Journal of Chemistry 58, no. 6 (December 2020): 798–803. http://dx.doi.org/10.1002/vjch.202000085.

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AbstractCondensation of 2‐((1H‐benzo[d]imidazol‐2‐yl)thio)acetic acid (1) with anthranilamide (2) in PEG‐600 (polyethylene glycol), at 100 oC for 3hr. gave 2‐(((1H‐benzo[d]imidazol‐2‐yl)thio)methyl)quinazolin‐4(3H)‐one (3). Treatment of 3 with DMS, DES and Ph‐CH2‐Cl, individually in PEG‐600, at RT for 1 hr. without using any base, followed by easy process resulted in 4 (a‐c). The later on reaction with H2O2 in PEG‐600, for 3 hr, without using any base, followed by simple processing resulted in 5 (a‐c). Alternatively, 5 (a‐c) the sequence of reactions could be prepared by tandem procedure with good yields. Thus novel quinazolinone products have been prepared with new synthetic routes and strategies by using PEG‐600 as solvent, in polyethylene glycol (PEG‐600) in four routes. i.e. (tandem‐1, tandem‐2, stepwise‐1 and stepwise‐2) Probably, this is the first case of four variable but identical end‐products‐ giving tandem syntheses, under green conditions, of 5 (a‐c). Obviously, as figures pointed out, tandem‐1 route gave good yields compared to the stepwise routes. In this process PEG‐600 recycled and reused.

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Tao, Yangchun, Siwei Liu, Yi Zhang, Zhenguo Chi, and Jiarui Xu. "A pH-responsive polymer based on dynamic imine bonds as a drug delivery material with pseudo target release behavior." Polymer Chemistry 9, no. 7 (2018): 878–84. http://dx.doi.org/10.1039/c7py02108a.

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In this study, pentaerythritol tetra(3-mercaptopropionate)-allylurea-poly(ethylene glycol) (PETMP-AU-PEG), produced by the Schiff-base reaction between terminal-aldehyded PEG and PETMP-AU, was used to prepare doxorubicin (DOX)-loaded polymers for triggered release.

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Wang, Shiwen, Guanjiang Liu, Bei Yang, Zifeng Zhang, Debo Hu, Chenchen Wu, Yaling Qin, Qian Dou, Qing Dai, and Wenping Hu. "Low-fouling CNT-PEG-hydrogel coated quartz crystal microbalance sensor for saliva glucose detection." RSC Advances 11, no. 37 (2021): 22556–64. http://dx.doi.org/10.1039/d1ra02841c.

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We successfully achieved the direct detection of saliva glucose by a CNT-PEG-hydrogel. The top CNT-PEG layer provides channels for transporting glucose molecules and filters macromolecular impurities and the bottom base PBA-hydrogel film provides the glucose binding sites.

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Mikesell, Logan, Dhananjani N. A. M. Eriyagama, Yipeng Yin, Bao-Yuan Lu, and Shiyue Fang. "Stepwise PEG synthesis featuring deprotection and coupling in one pot." Beilstein Journal of Organic Chemistry 17 (December 28, 2021): 2976–82. http://dx.doi.org/10.3762/bjoc.17.207.

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The stepwise synthesis of monodisperse polyethylene glycols (PEGs) and their derivatives usually involves using an acid-labile protecting group such as DMTr and coupling the two PEG moieties together under basic Williamson ether formation conditions. Using this approach, each elongation of PEG is achieved in three steps – deprotection, deprotonation and coupling – in two pots. Here, we report a more convenient approach for PEG synthesis featuring the use of a base-labile protecting group such as the phenethyl group. Using this approach, each elongation of PEG can be achieved in two steps – deprotection and coupling – in only one pot. The deprotonation step, and the isolation and purification of the intermediate product after deprotection using existing approaches are no longer needed when the one-pot approach is used. Because the stepwise PEG synthesis usually requires multiple PEG elongation cycles, the new PEG synthesis method is expected to significantly lower PEG synthesis cost.

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Cherpakov, Alexander V., Ivan A. Parinov, and Rakesh Kumar Haldkar. "Parametric and Experimental Modeling of Axial-Type Piezoelectric Energy Generator with Active Base." Applied Sciences 12, no. 3 (February 7, 2022): 1700. http://dx.doi.org/10.3390/app12031700.

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A computational and experimental approach to modeling oscillations of a new axial-type piezoelectric generator (PEG) with an attached mass and an active base is considered. A pair of cylindrical piezoelements located along the generator axis is used as an active base. Plate-type piezoelectric elements, made in the form of two bimorphs on an elastic PEG base, use the potential energy of PEG bending vibrations. Energy generation in cylindrical piezoelectric elements occurs due to the transfer of compressive forces to the piezoelectric element at the base of the PEG during excitation of structural vibrations. The active load scheme is selected separately for each piezoelectric element. Numerical simulation was performed in the ANSYS FE analysis package. The results of modal and harmonic analysis of vibrations are presented. A technique for experimental analysis of vibrations is presented, and a laboratory test setup is described. Numerical and experimental results are presented for the output characteristics of a piezoelectric generator at a low-frequency load. For one of the versions of the generator and a certain displacement amplitude for a frequency of 39 Hz, in the results of a comparative experimental analysis at a load of 10 kΩ, the maximum output power for each cylindrical piezoelectric element was 2138.9 μW, and for plate-type piezoelectric elements, respectively, 446.9 μW and 423.2 μW.

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Cabrales, Pedro, Amy G. Tsai, Robert M. Winslow, and Marcos Intaglietta. "Extreme hemodilution with PEG-hemoglobin vs. PEG-albumin." American Journal of Physiology-Heart and Circulatory Physiology 289, no. 6 (December 2005): H2392—H2400. http://dx.doi.org/10.1152/ajpheart.00225.2005.

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Isovolemic hemodilution to 11% systemic hematocrit was performed in the hamster window chamber model using 6% dextran 70 kDa (Dx 70) and 5% human serum albumin (HSA). Systemic and microvascular effects of these solutions were compared with polyethylene glycol (PEG)-conjugated 5% albumin (MPA) and PEG-conjugated 4.2% Hb (MP4). These studies were performed for the purpose of comparing systemic and microvascular responses of PEG vs. non-PEG plasma expanders and similar oxygen-carrying vs. noncarrying blood replacement fluids. Mean arterial blood pressure was statistically significantly reduced for all groups compared with baseline ( P < 0.05), HSA, MPA, and MP4 higher than Dx 70 ( P < 0.05). MP4 and MPA had a significantly higher cardiac index than HSA and Dx 70, in addition to a positive base excess. Microvascular blood flow and capillary perfusion were significantly higher for the PEG compounds compared with HSA and Dx 70. Intravascular Po2 for MP4 and MPA was higher in arterioles ( P < 0.05) compared with HSA and Dx 70, but there was no difference in either tissue or venular Po2 between groups. Total Hb in the MP4 group was 4.8 ± 0.4 g/dl, whereas the remaining groups had a range of 3.6–3.8 g/dl. The hemodilution results showed that PEG compounds maintained microvascular conditions with lower concentrations than conventional plasma expanders. Furthermore, microvascular oxygen delivery and extraction in the window chamber tissue were significantly higher for the PEG compounds. MP4 was significantly higher than MPA ( P < 0.05) and was not statistically different from baseline, an effect due to the additional oxygen release to the tissue by the Hb MP4.

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Peter, Philippe, Christophe Plessis, and Gérard Riess. "Agglomération contrôlée de latex par formation de complexes tensioactifs anioniques : copolymères à blocs à base de poly(oxyde d’éthylène)." Comptes Rendus Chimie 6, no. 11-12 (November 2003): 1403–10. http://dx.doi.org/10.1016/j.crci.2003.10.002.

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Ilhami, Fasih Bintang, Enyew Alemayehu Bayle, and Chih-Chia Cheng. "Complementary Nucleobase Interactions Drive Co-Assembly of Drugs and Nanocarriers for Selective Cancer Chemotherapy." Pharmaceutics 13, no. 11 (November 15, 2021): 1929. http://dx.doi.org/10.3390/pharmaceutics13111929.

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A new concept in cooperative adenine–uracil (A–U) hydrogen bonding interactions between anticancer drugs and nanocarrier complexes was successfully demonstrated by invoking the co-assembly of water soluble, uracil end-capped polyethylene glycol polymer (BU-PEG) upon association with the hydrophobic drug adenine-modified rhodamine (A-R6G). This concept holds promise as a smart and versatile drug delivery system for the achievement of targeted, more efficient cancer chemotherapy. Due to A–U base pairing between BU-PEG and A-R6G, BU-PEG has high tendency to interact with A-R6G, which leads to the formation of self-assembled A-R6G/BU-PEG nanogels in aqueous solution. The resulting nanogels exhibit a number of unique physical properties, including extremely high A-R6G-loading capacity, well-controlled, pH-triggered A-R6G release behavior, and excellent structural stability in biological media. Importantly, a series of in vitro cellular experiments clearly demonstrated that A-R6G/BU-PEG nanogels improved the selective uptake of A-R6G by cancer cells via endocytosis and promoted the intracellular release of A-R6G to subsequently induce apoptotic cell death, while control rhodamine/BU-PEG nanogels did not exert selective toxicity in cancer or normal cell lines. Overall, these results indicate that cooperative A–U base pairing within nanogels is a critical factor that improves selective drug uptake and effectively promotes apoptotic programmed cell death in cancer cells.

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Wang, Huiru, Yanmin Wang, Xian Li, Min Chen, Yanling Wu, Cuicui Sun, and Xiaoning Wang. "Antiaging Property and Mechanism of Phase-Change Asphalt with PEG as an Additive." Advances in Materials Science and Engineering 2020 (November 22, 2020): 1–10. http://dx.doi.org/10.1155/2020/7598049.

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In this study, phase-change asphalt was prepared with polyethylene glycol (PEG-1000) as a modifier. The short- and long-term antiaging performances were characterized by rolling-thin-film-oven (RTFOT) and pressure-aging vessel (PAV) tests, respectively. The functional groups and “bee structures” of PEG-modified asphalt and base asphalt were characterized by Fourier transform infrared absorption spectroscopy (FTIR) and atomic force microscopy (AFM). The research results indicate that the additive of PEG can improve the high-temperature, temperature sensitivity, and the antiaging properties of asphalt. The FTIR reveals that only physical blending and no chemical reaction occurs between PEG and asphalt. AFM topography indicates that smaller “bee structures” appear on the surface of PEG-modified asphalt and these structures do not change during aging.

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Hendrick, Erin, and Margaret Frey. "Increasing Surface Hydrophilicity in Poly(Lactic Acid) Electrospun Fibers by Addition of Pla-b-Peg Co-Polymers." Journal of Engineered Fibers and Fabrics 9, no. 2 (June 2014): 155892501400900. http://dx.doi.org/10.1177/155892501400900219.

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Poly (lactic acid) – b – poly (ethylene glycol) (PLA-b-PEG) co-polymers with block lengths of 1000–750, 5000–1000, 1000–5000, and bulk PEG were added to PLA electrospinning dopes to create hydrophilic but non-water soluble nanofibers. PLA-b-PEG block lengths strongly affected the total amount of PEG that could be incorporated, as well as spinnability and fiber morphology. Solutions containing >1% w/w of the lowest molecular weight co-polymer PLA (1000) – b – PEG (750) formed an unspinnable, cloudy gel. Addition of the PLA (5000) – b – PEG (1000) to the base spinning solution influenced fiber diameters and spinnability in the same manner as simply increasing PLA concentration in the spinning dope. Addition of PLA (1000) – b – PEG (5000) resulted in decreased fiber diameters, and allowed for the highest overall co-polymer loading. In final fiber formulations, maximums of 0.9, 2.9 and 9.3 wt% PEG could be achieved using the PLA-b-PEG 1000–750, 5000–1000 and 1000–5000 respectively. PEG (MW = 3350 g/mol) homopolymer was added to the spinning dopes to prepare fibers with 1.0 and 5.0 wt% PEG. The resulting fibers had non-uniform morphology and more variable diameter size than occurred with the addition of PEG in block co-polymer form. Water absorbance by electrospun nonwoven fabrics increased by four times over the control PLA with the addition of 1.0 wt% PEG, and by eighteen times with the addition of 9.3 wt% PEG with the block co-polymers. At similar overall PEG loadings, the addition of PLA-b-PEG resulted in a two to four fold increase in water wicking over the addition of PEG homopolymer.

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Wang, Zijia, Yawen Chang, Siyang Jia, and Fujuan Liu. "Preparation and Properties of Polyimide/Polysulfonamide/Polyethylene Glycol (PI/PSA/PEG) Hydrophobic Nanofibrous Membranes." Materials 17, no. 16 (August 21, 2024): 4135. http://dx.doi.org/10.3390/ma17164135.

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In this study, polyimide (PI) and polysulfonamide (PSA) were used as base materials, and polyethylene glycol (PEG) was added to successfully prepare PI/PSA/PEG nanofiber membranes through electrospinning technology. Subsequently, water etching was performed on the membranes, utilizing the water solubility of PEG to form the rough wrinkled structure, further enhancing the surface hydrophobicity. The experimental results showed that under the conditions of a spinning voltage of 10 kV, PI/PSA mass fraction of 15 wt.%, and PEG-to-PI/PSA mass ratio of 1/3, the obtained fiber membranes exhibit a uniform morphology (an average diameter of 0.73 µm) and excellent hydrophobicity (the initial water contact angle (WCA) reaching 130.4°). After PEG water etching, the surface of the PI/PSA/PEG hydrophobic membranes formed the rough wrinkled structure, which not only improved their mechanical properties but also further enhanced their hydrophobicity (the initial WCA increasing to 137.9°). Hence, fiber membranes are expected to have broad application prospects in fields such as waterproofing and moisture permeability.

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Szulc-Musioł, Beata, Lucyna Bułaś, and Barbara Dolińska. "Formulation, characterization, and in vitro evaluation release nimesulide from different rectal suppository bases." Acta Poloniae Pharmaceutica - Drug Research 79, no. 6 (March 3, 2023): 865–73. http://dx.doi.org/10.32383/appdr/159289.

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Nimesulide is a poorly water-soluble, non-steroidal anti-inflammatory drug for both systemic and topical application. The aim of the study was to assess the influence of the type of base and surfactants (Tween80, Span80, soy lecithin, sodium lauryl sulphate) on drug release from rectal suppositories. Suppositories were prepared in the Unquator® using Cacao butter, Witepsol H15 and PEG1500:PEG400 as a base. The physicochemical properties of the prepared suppositories were in accordance to the Pharmacopoeia’s requirements. In vitro dissolution profile of the formulations was evaluated using USP apparatus 1. It has been shown that most of the nimesulide was released from suppositories prepared on PEG base. Addition of 2% surfactant to lipophilic base suppositories, significantly increased the amount of nimesulide released from all the investigated formulae. Among the formulations containing surfactants, only Witepsol H15 with Span 80 released a nearly complete drug during 210 minutes. The results indicate that the First-Order model is the best fit with the nimesulide in-vitro release from lipophilic suppositories, while the Higuchi model - to the PEG suppositories. The drug release kinetics from suppositories showed that the Cacao butter bases adequately fit data for zero-order kinetics model, while the Higuchi model - for the PEG suppositories.

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Jalloh, Umu S., Arielle Gsell, Kirstene A. Gultian, James MacAulay, Abigail Madden, Jillian Smith, Luke Siri, and Sebastián L. Vega. "Synthesis and Photopatterning of Synthetic Thiol-Norbornene Hydrogels." Gels 10, no. 3 (February 23, 2024): 164. http://dx.doi.org/10.3390/gels10030164.

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Hydrogels are a class of soft biomaterials and the material of choice for a myriad of biomedical applications due to their biocompatibility and highly tunable mechanical and biochemical properties. Specifically, light-mediated thiol-norbornene click reactions between norbornene-modified macromers and di-thiolated crosslinkers can be used to form base hydrogels amenable to spatial biochemical modifications via subsequent light reactions between pendant norbornenes in the hydrogel network and thiolated peptides. Macromers derived from natural sources (e.g., hyaluronic acid, gelatin, alginate) can cause off-target cell signaling, and this has motivated the use of synthetic macromers such as poly(ethylene glycol) (PEG). In this study, commercially available 8-arm norbornene-modified PEG (PEG-Nor) macromers were reacted with di-thiolated crosslinkers (dithiothreitol, DTT) to form synthetic hydrogels. By varying the PEG-Nor weight percent or DTT concentration, hydrogels with a stiffness range of 3.3 kPa–31.3 kPa were formed. Pendant norbornene groups in these hydrogels were used for secondary reactions to either increase hydrogel stiffness (by reacting with DTT) or to tether mono-thiolated peptides to the hydrogel network. Peptide functionalization has no effect on bulk hydrogel mechanics, and this confirms that mechanical and biochemical signals can be independently controlled. Using photomasks, thiolated peptides can also be photopatterned onto base hydrogels, and mesenchymal stem cells (MSCs) attach and spread on RGD-functionalized PEG-Nor hydrogels. MSCs encapsulated in PEG-Nor hydrogels are also highly viable, demonstrating the ability of this platform to form biocompatible hydrogels for 2D and 3D cell culture with user-defined mechanical and biochemical properties.

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Qu, Yuanyuan, Jinlong Li, Xin Jia, and Lijun Yin. "Schiff Base-Crosslinked Tetra-PEG-BSA Hydrogel: Design, Properties, and Multifunctional Functions." Journal of Functional Biomaterials 16, no. 2 (February 18, 2025): 69. https://doi.org/10.3390/jfb16020069.

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Hydrogel network structures play a crucial role in determining mechanical properties and have broad applications in biomedical and industrial fields. Therefore, their rational design is essential. Herein, we developed a Schiff base-crosslinked hydrogel through the reaction of Tetra-armed polyethylene glycol with aldehyde end groups (Tetra-PEG-CHO) and bovine serum albumin (BSA) under alkaline conditions. In addition, the Tetra-PEG-BSA hydrogel showed a rapid gelation time of around 11 s, much faster than that of the GLU-BSA, HT-BSA, and GDL-BSA hydrogels. It had high optical transmittance (92.92% at 600 nm) and swelling ratios superior to the other gels in different solutions, maintaining structural integrity even in denaturing environments such as guanidine hydrochloride and SDS. Mechanical tests showed superior strain at break (84.12 ± 0.76%), rupture stress (28.64 ± 1.21 kPa), and energy dissipation ability (468.0 ± 34.9 kJ·m−3), surpassing all control group hydrogels. MTT cytotoxicity assays indicated that cell viability remained >80% at lower concentrations, confirming excellent biocompatibility. These findings suggest that Tetra-PEG-BSA hydrogels may serve as effective materials for drug delivery, tissue engineering, and 3D printing.

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Zacharuk, Mario, Daniela Becker, Luiz A. F. Coelho, and Sergio H. Pezzin. "Estudo da reação entre polietileno glicol e resina epoxídica na presença de N,N-dimetilbenzilamina." Polímeros 21, no. 1 (February 11, 2011): 73–77. http://dx.doi.org/10.1590/s0104-14282011005000009.

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Neste trabalho foi estudada a reação entre polietileno glicol (PEG) e uma resina epoxídica à base de diglicidil éter de bisfenol A (DGEBA), na presença de N,N-dimetilbenzilamina (DMBA), sendo os produtos desta reação avaliados por espectroscopia no infravermelho (FTIR), espectroscopia de ressonância magnética nuclear de próton (RMN-1H) e medidas de viscosidade cone-prato. Amostras curadas com um endurecedor à base de poliamina foram também submetidas a ensaios de tração e calorimetria exploratória diferencial (DSC). Os resultados das análises de viscosidade, FTIR e RMN (1H) confirmaram a ocorrência da reação entre grupos epóxi do DGEBA e grupos hidroxila do PEG na presença de DMBA, a 100 ºC. As análises de DSC e os ensaios de tração dos sistemas curados mostram que a reação de DGEBA com PEG gera um material com temperatura de transição vítrea (Tg) significativamente menor, em conjunto com o aumento da deformação na ruptura e decréscimo do modulo de elasticidade, quando comparados ao sistema epoxídico de referência (DGEBA).

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Tanaka, Yuta, Hisashi Doi, Yasuhiko Iwasaki, T. Yoneyama, and Takao Hanawa. "Immobilization of Poly(Ethylene Glycol) Terminated with Amine to Titanium Surface by Electrodeposition." Advanced Materials Research 15-17 (February 2006): 205–8. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.205.

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In many applications such as catheters, artificial blood vessels and diagnostic sensors, blood compatibility or prevention of adhesion of platelet is required. The preferred way to control these purposes is to eliminate or drastically reduce the adsorption of proteins. Surface modification with Poly(ethylene glycol), PEG has long been known to reduce undesirable protein adsorption. No technique for the immobilization of PEG to base metal has been developed. In this study, PEG terminated at both terminals or one terminal with amine bases was immobilized onto titanium surface by immersion or electrodeposition. The bonding manners of PEG onto titanium, which involve directionality of terminated amines and chemical bonding states of interface between the deposited PEG layer and TiO2, were characterized using X-ray photoelectron spectroscopy, XPS. As a result, terminated amines locate inside of the PEG layer and combine mainly with TiO2 as stable NHO by electrodeposition, while amines randomly exist and show mainly unstable bonding with TiO2 by immersion. Moreover, the difference of amine termination leads to different bonding manners, U-shape in PEG terminated both terminals and brush in PEG terminated one terminal. This immobilization process is one-stage convenient technique and useful for all electroconductive and morphological materials.

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Kampars, Valdis, Ruta Kampare, and Aija Krumina. "MgO Catalysts for FAME Synthesis Prepared Using PEG Surfactant during Precipitation and Calcination." Catalysts 12, no. 2 (February 16, 2022): 226. http://dx.doi.org/10.3390/catal12020226.

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To develop a method for the preparation of MgO nanoparticles, precatalyst synthesis from magnesium nitrate with ammonia and calcination was performed in presence of PEG in air. Without PEG, the catalysts are inactive. The conversion to hydroxide was performed using a PEG/MgO molar ratio of 1, but, before the calcination, excess of PEG was either saved (PEG1) or increased to 2, 3, or 4 (PEG 2–4). Catalysts were calcined at 400–660 °C and characterized using XRD, N2 adsorption-desorption, TGA, FTIR, and SEM. The FAME yield in the reactions with methanol depend on the PEG ratio used and the calcination temperature. The optimal calcination temperature and highest FAME yield in the 6 h reactions for catalysts PEG1, PEG2, PEG3 and PEG4 were 400 °C, 74%; 500 °C, 80%; 500 °C, 51% and 550 °C, 31%, respectively. The yield dependence on calcination temperature for catalysts with a constant PEG ratio is similar to that of a bell curve, which becomes wider and flatters with an increase in PEG ratio. For most catalysts, the FAME yield increases as the size of the crystallites decreases. The dependence of FAME and the intermediate yield on oil conversion confirms that all catalysts have strong base sites.

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CATIKER, Efkan, Temel OZTURK, Bedrettin SAVAS, Mehmet ATAKAY, and Bekir SALIH. "Synthesis of Novel Aba-Type Amphiphilic Copolymers Including 2-Hydroxypropyl Propionate and N-Isobutoxymethyl Β-Alanine by Peg-Dialkoxide Initiated Hydrogen-Transfer Polymerization." Eurasia Proceedings of Science Technology Engineering and Mathematics 15 (December 31, 2021): 21–27. http://dx.doi.org/10.55549/epstem.1052148.

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Novel ABA-type amphiphilic copolymers were prepared using end-groups activated poly (ethylene glycol) (PEG) as an initiator of hydrogen-transfer polymerization (HTP). For this purpose, PEG with 1450 Da (PEG-1450) was treated with the equivalent amount of sodium hydride to synthesize PEG with dialkoxide end-groups, namely PEG-dialkoxide. Using the PEG-dialkoxide as a macroinitiator, base-catalysed HTP of 2-hydroxypropyl acrylate (HPA), and N-isobutoxymethyl acrylamide (BMA) were performed to achieve the novel ABA-type block copolymers. The copolymers were obtained with relatively high yields. Characterization of the ABA-type amphiphilic copolymers was carried out using FTIR and MALDI mass spectrometry. FTIR spectra of the copolymers exhibited some characteristic bands assigning to the functional groups arising from the mechanism of HTP. Molar mass distributions of the copolymers from the MALDI mass study pointed out that chain extensions by mass in each copolymer were almost equal. Hence, the MALDI mass spectra of the copolymers revealed that chain extensions of PEGs by HPA, and BMA units were successfully fulfilled.

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Shekouhy, Mohsen, and Ali Khalafi-Nezhad. "Polyethylene glycol-bonded 1,8-diazabicyclo[5.4.0]undec-7-ene (PEG–DBU) as a surfactant-combined base catalyst for the application of nucleosides as reagents in multi-component syntheses of 8-substituted pyrido[2,3-d]pyrimidine-6-carbonitriles in water." Green Chemistry 17, no. 10 (2015): 4815–29. http://dx.doi.org/10.1039/c5gc01448d.

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Huet, Lucie A., Hannah M. Emnett, and Mitra J. Z. Hartmann. "Demonstration of three-dimensional contact point determination and contour reconstruction during active whisking behavior of an awake rat." PLOS Computational Biology 18, no. 9 (September 15, 2022): e1007763. http://dx.doi.org/10.1371/journal.pcbi.1007763.

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The rodent vibrissal (whisker) system has been studied for decades as a model of active touch sensing. There are no sensors along the length of a whisker; all sensing occurs at the whisker base. Therefore, a large open question in many neuroscience studies is how an animal could estimate the three-dimensional (3D) location at which a whisker makes contact with an object. In the present work we simulated the shape of a real rat whisker to demonstrate the existence of several unique mappings from triplets of mechanical signals at the whisker base to the three-dimensional whisker-object contact point. We then used high speed video to record whisker deflections as an awake rat whisked against a peg, and used the mechanics resulting from those deflections to extract the contact points along the peg surface. These results demonstrate that measurement of specific mechanical triplets at the base of a biological whisker can enable 3D contact point determination during natural whisking behavior. The approach is viable even though the biological whisker has non-ideal, non-planar curvature, and even given the rat’s real-world choices of whisking parameters. Visual intuition for the quality of the approach is provided in a video that shows the contour of the peg gradually emerging during active whisking behavior.

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Wang, Lin, Fang Liu, and Si Tong Cao. "Study on Preparation and Properties of High Permeability Polyurethane Composites with Low Swelling." Advanced Materials Research 750-752 (August 2013): 16–19. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.16.

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The water vapor permeability and water-swelling property of Polyurethane (PU) membranes with hydrophilic group and the PU composites were investigated. The water vapor permeability of the PU membranes increases with increasing polyethylene glycol (PEG) content. The highest water vapor permeability of PU membrane reaches 5,500 g/m2×24h, whose expansion ratio reaches fifty-eight percent. The PU composites have three PU layers. The best surface layer of the composite is PU with fifteen percent PEG content, and the best base layer is PU with one hundred percent PEG content. The middle layer uses PU with PEG content from fifty to one hundred percent. The water vapor permeability of the PU composites can reach 4,000 g/m2×24h, and the water-expansion ratio of the composites is below four percent when the surface layer of the composites contacts with water.

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Justin, Richard, and Biqiong Chen. "Multifunctional chitosan–magnetic graphene quantum dot nanocomposites for the release of therapeutics from detachable and non-detachable biodegradable microneedle arrays." Interface Focus 8, no. 3 (April 20, 2018): 20170055. http://dx.doi.org/10.1098/rsfs.2017.0055.

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Biodegradable chitosan–magnetic graphene quantum dot (MGQD) nanocomposites were prepared and investigated for the release of small and large molecular weight (MWt) therapeutics from detachable and non-detachable biodegradable microneedle arrays. The presence of MGQDs in chitosan increased the electrical conductivity and biodegradation rate of chitosan while maintaining its mechanical properties. The detachable microneedle arrays were created by including a water-soluble ring of poly(ethylene glycol) (PEG) at the base of the microneedle, which enabled the rapid detachment of the microneedle shaft from the base. The PEG ring did not impede the microneedle array performance, with mechanical properties and a drug release profile of low MWt lidocaine hydrochloride similar to microneedle arrays without the ring. Without the PEG ring, the chitosan–MGQD microneedles were electrically conductive and allowed for electrically stimulated release of large MWt therapeutics which was challenging without the stimulation. These results demonstrate that chitosan nanocomposites containing MGQDs with intrinsic photoluminescent and supermagnetic properties are promising materials for developing multifunctional microneedles for targeted and tracked transdermal drug delivery.

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Ren, Jiaoyu, Yanxi Zhu, Hongyun Xuan, Xuefan Liu, Zhichao Lou, and Liqin Ge. "Highly transparent and self-healing films based on the dynamic Schiff base linkage." RSC Advances 6, no. 116 (2016): 115247–51. http://dx.doi.org/10.1039/c6ra23886f.

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Cabrales, Pedro, Fantao Meng, and Seetharama A. Acharya. "Tissue oxidative metabolism after extreme hemodilution with PEG-conjugated hemoglobin." Journal of Applied Physiology 109, no. 6 (December 2010): 1852–59. http://dx.doi.org/10.1152/japplphysiol.00344.2010.

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NADH-localized fluorometry was used as a noninvasive technique to monitor changes in the energy state of intact tissue (muscle and connective tissue), without anesthesia, as a function of blood plasma O2-carrying capacity in the hamster window chamber model. Acute moderate isovolemic hemodilution was induced by two isovolemic hemodilution steps: in the first step, 6% 70-kDa dextran (Dex70) was used to induce an acute anemic state (18% Hct); in the second step, exchange transfusion of polyethylene glycol (PEG) maleimide-conjugated Hb (4 g/dl, PEG-Hb) or Dex70 (6 g/dl) was used to reduce erythrocytes to 75% of baseline (11% Hct). PEG-Hb had six copies of PEG (5 kDa) conjugated to each human Hb (0.48 g PEG/g Hb) through extension arm-facilitated chemistry. Systemic parameters, microvascular perfusion, functional capillary density, intravascular and interstitial Po2, and intracellular NADH fluorescence were monitored. Mean arterial blood pressure after extreme hemodilution was statistically significantly reduced for Dex70 compared with PEG-Hb. The presence of PEG-Hb in the circulation maintained positive acid-base balance. While microvascular blood flows were not different, functional capillary density was significantly higher for PEG-Hb than Dex70. Arteriolar Po2 was higher in the presence of PEG-Hb than Dex70, but tissue and venular Po2 were not different. Cellular energy metabolism (intracellular O2) in the tissues was improved with PEG-Hb. Moderate hemodilution to 18% Hct (6.4 g Hb/dl) brings tissue O2 delivery to the verge of inadequacy. Extreme hemodilution to 11% Hct (3.7 g Hb/dl) produces tissue anoxia, and high-O2-affinity PEG-Hb (Po2 at which blood is 50% saturated with O2 = 4 Torr, 1.1 g Hb/dl) only partially decreases anaerobic metabolism without increasing tissue Po2.

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Shields, Vonnie D. C. "Ultrastructure of the aporous sensilla on the galea of larval Mamestra configurata (Walker) (Lepidoptera: Noctuidae)." Canadian Journal of Zoology 72, no. 11 (November 1, 1994): 2032–54. http://dx.doi.org/10.1139/z94-274.

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The galea of fifth-instar Bertha armyworms, Mamestra configurata, has three types of aporous sensilla: one spire-shaped basiconic peg, two short basiconic pegs, and one campaniform sensillum. The spire-shaped peg is set in an inflexible socket, innervated by three bipolar neurons, and enveloped by three sheath cells. One microtubule-laden dendrite completely fills the distal portion of the dendritic sheath and ends within the peg. It is joined by a lamellate and a scolopidium-like dendrite that end near and below the base of the peg, respectively. The ciliary sinus is large and the membrane of the enveloping inner sheath cell is highly elaborate. This sensillum exhibits features characteristic of thermo-hygrosensilla. The short basiconic pegs and campaniform sensillum are each innervated by a single bipolar neuron and each is associated with three sheath cells. In both sensilla, the dendrite ends in a tubular body, typical of mechanosensilla.

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Wagner, Victoria E., and James D. Bryers. "Monocyte/macrophage interactions with base and linear- and star-like PEG-modified PEG-poly(acrylic acid) co-polymers." Journal of Biomedical Materials Research 66A, no. 1 (June 23, 2003): 62–78. http://dx.doi.org/10.1002/jbm.a.10516.

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Aldabbagh, Maha, Baker F. Abdallaha, Nibras Y. Abdulla, and Ibraheem J. Ibraheem. "Synthesis, Characterization and Anticancer Activity of Chitosan Schiff Base / PEG Blend Doped with Gold and Silver Nanoparticles in Treatment of Breast Cancer Cell Line MCF-7." Iraqi Journal of Pharmaceutical Sciences( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) 33, no. 2 (June 29, 2024): 101–11. http://dx.doi.org/10.31351/vol33iss2pp101-111.

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In the present study, chitosan Schiff base has been prepared from chitosan reaction with the para chloro benzaldehyde. The AuNPs and AgNPs were manufacture by extract of onion peels as a reducing agent. The AuNPs and AgNPs that have been synthesized were characterized through UV-vis spectroscopy the XRD analyses and SEM microscopy. The polymer blends of the chitosan / PEG has been prepared through using the approach of solution casting. Chitosan Schiff base / PEG Au and Ag nano-composites were synthesized nano composites and polymer blends have been characterized by FTIR which confirm the formation of Schiff base by revealing a new band of absorption at 1693 cm-1 as a result of the (C=N) imine group. FESEM, DSC and TGA confirms the thermal stability of the prepared polymer blends and nanocomposites, nano composites have shown good results in inhibiting breast cancer cell line MCF-7, IC50 of nanocomposite = 19.44 µg / mL.

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34

Yeler, Erdal Eren, Metin Tosun, and Aras Türkoğlu. "Mitigating Osmotic Drought Stress in Rye: Assessing the Ameliorative Effects of Putrecine on Germination, Seedling and Mitotic Index." Erzincan Üniversitesi Fen Bilimleri Enstitüsü Dergisi 17, no. 3 (September 3, 2024): 718–35. https://doi.org/10.18185/erzifbed.1432960.

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Abstract In this study, the impact of putrescine, a polyamine, on the germination, seedling growth, and mitotic index of rye seeds (cv. Aslım-95) was investigated under osmotic drought conditions induced by polyethylene glycol (PEG-6000) application. The experiment involved six different PEG doses (-2, -4, -6, -8, and -10 bars) in combination with putrescine doses of 0.001, 0.01, and 0.1 mM. The concentration of -2 bars of polyethylene glycol, representing osmotic drought, positively influenced some of the studied characteristics. However, the stimulative effect of -2 bars of osmotic drought exhibited minimal changes with PEG 6000 + putrescine combinations. Conversely, as the osmotic drought level (PEG 6000 concentration) increased beyond that concentration, all the observed characteristics were negatively impacted. All putrescine doses used in combination with PEG 6000 demonstrated positive effects on the examined characteristics and reduced the germination duration. The most significant effect of putrescine was observed at a concentration of 0.1 mM on the base dry weight and 0.001 mM concentration on all other characteristics. Consequently, high doses of osmotic drought stress, particularly, adversely affected germination and seedling growth. It was determined that all putrescine doses could partially alleviate the negative effects induced by osmotic drought caused by PEG 6000.

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35

Valenzuela Villela, Karen Sofia, Karen Valeria Alvarado Araujo, Perla Elvia Garcia Casillas, and Christian Chapa González. "Protective Encapsulation of a Bioactive Compound in Starch–Polyethylene Glycol-Modified Microparticles: Degradation Analysis with Enzymes." Polymers 16, no. 14 (July 20, 2024): 2075. http://dx.doi.org/10.3390/polym16142075.

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Starch is a promising polymer for creating novel microparticulate systems with superior biocompatibility and controlled drug delivery capabilities. In this study, we synthesized polyethylene glycol (PEG)-modified starch microparticles and encapsulated folic acid using a solvent-mediated acid-base precipitation method with magnetic stirring, which is a simple and effective method. To evaluate particle degradation, we simulated physiological conditions by employing an enzymatic degradation approach. Our results with FTIR and SEM confirmed the successful synthesis of starch–PEG microparticles encapsulating folic acid. The average size of starch microparticles encapsulating folic acid was 4.97 μm and increased to 6.01 μm upon modification with PEG. The microparticles were first exposed to amylase at pH 6.7 and pepsin at pH 1.5 at different incubation times at physiological temperature with shaking. Post-degradation analysis revealed changes in particle size and morphology, indicating effective enzymatic degradation. FTIR spectroscopy was used to assess the chemical composition before and after degradation. The initial FTIR spectra displayed characteristic peaks of starch, PEG, and folic acid, which showed decreased intensities after enzymatic degradation, suggesting alterations in chemical composition. These findings demonstrate the ongoing development of starch–PEG microparticles for controlled drug delivery and other biomedical applications and provide the basis for further exploration of PEG–starch as a versatile biomaterial for encapsulating bioactive compounds.

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Hazer, Derya Burcu, Baki Hazer, and Nazmiye Dinçer. "Soft Tissue Response to the Presence of Polypropylene-G-Poly(ethylene glycol) Comb-Type Graft Copolymers Containing Gold Nanoparticles." Journal of Biomedicine and Biotechnology 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/956169.

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The aim of this study is to evaluate the soft tissue response of the pure and Au-embedded PPg-PEG. PP-g-PEG2000, PP-g-PEG4000, Au-PP-g-PEG2000, and AuPP-g-PEG4000 were obtained via chlorination of polypropylene and polyethylene glycol in the presence of a base with a “grafting onto” technique. Solvent cast films of these four copolymers with PP as a control group were embedded into five different rats. After 30 days of implantation, microscopic evaluation of inflammation and SEM analysis were done. PP had the most intense inflammatory reaction among the other polymers. PP-PEG block copolymers with high molecular weight and gold-nanoparticles-embedded ones revealed mild inflammatory reaction independently. SEM assessment revealed punched hole-like defects on the surface of all polymer samples except for PP. Graft copolymers with PEG, especially Au-attached ones, have favorable soft tissue response, and inflammatory reaction becomes milder as the number of PEG side chains increases.

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37

Martinah, Siti, RTM Sutamihardja, and Lilis Sugiarti. "OPTIMASI PERLAKUAN POLYETHYLENE GLIKOL (PEG) 6000 TERHADAP ISOLASI AGAROSA RUMPUT LAUT Glacilaria sp." Jurnal Sains Natural 4, no. 2 (December 3, 2017): 115. http://dx.doi.org/10.31938/jsn.v4i2.83.

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Optimation of Polyethylene Glycol (PEG) 6000 Treatment on Isolation of Agarose Seaweeds of Glacilaria sp Isolation of agarose from seaweeds (Glacilaria sp) had been done in acid, base, and neutral condition by using polyethylene glycol (PEG) method. Glacilaria sp, Seaweeds that used in this research was cultured by farmer in Muara Gembong, Bekasi. It used PEG with concentration 10%, 15%, 20%, 25%, & 30%. The scope of this research ware determination of seaweeds, seaweeds water content, isolation of agarose from seaweeds, and quality test of agarose. Parameter test of agarose quality include the strength of gel, the content of sulfat, measurement of galactose content and its proksimat. The high yield was 61,27% r in PEG 30%. The best quality of agarose was resulted in PEG 20% because of the highest strength of gel was 379,04 g/cm2.The lowest sulfat concentration was 1,33% and galactose was 17,39%.Key words: polyethylene glycol, PEG 6000, agarose, seaweeds, glacilaria sp ABSTRAK Isolasi agarosa dari rumput laut Glacilaria sp telah dilakukan dalam suasana asam, basa dan netral dengan metode polyethylene glikol (PEG). Rumput lauat yang digunakan adalah Gracilaria sp yang dibudidayakan oleh petani di Muara Gembong, Bekasi dengan perlakuan konsentrasi PEG 10%, 15%, 20%, 25% dan 30%. Ruang lingkup penelitian ini meliputi uji determinasi rumput laut, penetapan kadar air rumput laut, isolasi agarosa dari rumput laut, serta uji kualitas agarosa. Parameter pengujian kualitas agarosa terdiri dari kekuatan gel, kandungan sulfat, dan pengukuran kandungan galaktosa serta proksimatnya. Isolasi agarosa perlakuan konsentrasi polyethylene Glikol (PEG) 6000 pada rumput laut Glacilaria sp diperoleh rendemen paling tinggi terdapat pada perlakuan PEG 30% yaitu sebesar 61,27%. Akan tetapi untuk kualitas agarosa yang paling baik terdapat pada perlakuan konsentrasi PEG 20% karena diperoleh kekuatan gel paling tinggi sebesar 379,04 g/cm2. Kadar sulfat yang paling rendah sebesar 1,33% dan kadar galaktosa sebesar 17,39%.Kata Kunci: polyethylene glikol, PEG 6000, agarosa, rumput laut, glacilaria sp

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38

Helman, Laura, José Luiz Martins, Djalma José Fagundes, Edward Esteves, Cirilo de Paula Lima, and Álisson de Souza Costa. "Experimental antegrade enema: effects on water, electrolyte and acid-base balances with different solutions." Acta Cirurgica Brasileira 22, no. 5 (October 2007): 372–78. http://dx.doi.org/10.1590/s0102-86502007000500009.

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PURPOSE: To study the effects on the water, electrolyte, and acid-base balances in rabbits submitted to antegrade enema with different solutions through appendicostomy. METHODS: Forty male New Zealand rabbits were submitted to appendicostomy, and distributed in 4 groups, according to the antegrade enema solution: PEG group, polyethylene glycol electrolyte solution (n=10); ISS group, isotonic saline solution (n=10); GS group, glycerin solution (n=10); SPS group, sodium phosphate solution (n=10). After being weighed, arterial blood gas analysis, red blood count, creatinine and electrolytes were measured at 4 times: preoperatively (T1); day 6 postop, before enema (T2); 4h after enema (T3); and 24h after T3 (T4). RESULTS: In PEG group occurred Na retention after 4h, causing alkalemia, sustained for 24h with HCO3 retention. In ISS group occurred isotonic water retention and hyperchloremic acidosis after 4h, which was partially compensated in 24h. GS group showed metabolic acidosis after 4h, compensated in 24h. In SPS group occurred hypernatremic dehydration, metabolic acidosis in 4h, and hypokalemia, hypocalcemia, hypomagnesemia, and metabolic alkalosis with partially compensated dehydration in 24h. CONCLUSIONS: All solutions used in this study caused minor alterations on water, electrolyte or acid-base balances. The most intense ones were caused by hypertonic sodium phosphate solution (SPS) and isotonic saline solution (ISS) and the least by polyethyleneglycol electrolyte solution (PEG) and glycerin solution 12% (GS).

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Huang, Xue, Fang Yao, Ting Wei, and Mingzhong Cai. "A Highly Efficient and Recyclable Pd(Pph3)4/Peg-400 System for Stille Cross-Coupling Reactions of Organostannanes with Aryl Bromides." Journal of Chemical Research 41, no. 9 (September 2017): 547–50. http://dx.doi.org/10.3184/174751917x15045169836226.

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Pd(PPh3)4 in PEG-400 is shown to be a highly efficient catalyst for the Stille cross-coupling reactions of various organotin compounds with aryl bromides. The reaction could be conducted at 80 °C using NaOAc as base, yielding a variety of biaryls, alkynes and alkenes in good to excellent yields. The isolation of the products was readily performed by extraction with petroleum ether and the Pd(PPh3)4/PEG-400 system could be easily recycled and reused five times without any significant loss of activity.

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Winslow, Robert M., Armando Gonzales, Maria L. Gonzales, Michael Magde, Michael McCarthy, Ronald J. Rohlfs, and Kim D. Vandegriff. "Vascular resistance and the efficacy of red cell substitutes in a rat hemorrhage model." Journal of Applied Physiology 85, no. 3 (September 1, 1998): 993–1003. http://dx.doi.org/10.1152/jappl.1998.85.3.993.

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We have compared polyethylene glycol-modified bovine hemoglobin (PEG-Hb; high O2 affinity, high viscosity, high oncotic pressure) and human hemoglobin cross-linked between the α-chains (αα-Hb; low O2affinity, low viscosity, low oncotic pressure) with a non-O2-carrying plasma expander (pentastarch, high viscosity and oncotic pressure) after a 50% (by volume) exchange transfusion followed by a severe (60% of blood volume) hemorrhage. Mean arterial pressure and systemic vascular resistance rose significantly in the αα-Hb but not in the PEG-Hb animals. Two-hour survival was greater in the PEG-Hb animals (93%) than in control (35%), pentastarch (8%), or αα-Hb (6%) animals. In the PEG-Hb animals, there was no disturbance of acid-base balance, significantly less accumulation of lactic acid, and higher cardiac output than in the other groups. The data suggest that the rise in vascular resistance that follows αα-Hb exchange transfusion offsets the additional O2 transport provided by the cell-free hemoglobin. When resistance does not rise, as with PEG-Hb, even relatively small amounts of cell-free hemoglobin appear to be a very effective blood replacement.

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Chakraborty, Gurudas, Konstantin Balinin, Giuseppe Portale, Mark Loznik, Evgeny Polushkin, Tanja Weil, and Andreas Herrmann. "Electrostatically PEGylated DNA enables salt-free hybridization in water." Chemical Science 10, no. 43 (2019): 10097–105. http://dx.doi.org/10.1039/c9sc02598g.

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Electrostatic bonding of PEG molecules onto the backbone of DNA allows Watson–Crick base-pairing between individually PEGylated complementary strands resulting in a double helix with enhanced thermostability in salt-free aqueous medium.

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Molina, Brenda G., Luminita Cianga, Anca-Dana Bendrea, Ioan Cianga, Luis J. del Valle, Francesc Estrany, Carlos Alemán, and Elaine Armelin. "Amphiphilic polypyrrole-poly(Schiff base) copolymers with poly(ethylene glycol) side chains: synthesis, properties and applications." Polymer Chemistry 9, no. 31 (2018): 4218–32. http://dx.doi.org/10.1039/c8py00762d.

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Hsu, Chih Yueh, Chin Chung Wei, and Cho-Pei Jiang. "Tribological Study of PCL-PEG-PCL Polymer on SiN_xH_y Base." Key Engineering Materials 642 (April 2015): 264–69. http://dx.doi.org/10.4028/www.scientific.net/kem.642.264.

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Tribological behaviour of polymer and hard coating films is complicated with bio-lubricant. Contacting and kinematic conditions of a knee joint when a person in running was simulated in the study. Substrates of specimens are Ti6Al4V and 316LVM stainless steel. Two kinds of polymer films, PCL-PEG-PCL and mPEG-PCL-mPEG, were used to simulate the tissue of cartilage. The silicon nitride film, SiNxHy prepared by PECVD, was used as a protecting film, and it’s thickness about 1000 nm under the polymer film. The testing device was developed, upper specimen is rotated reversely and the lower one is moved linearly forward and backward for 6 mm. A frequency vibration is applied under the lower specimen to simulate the vibration caused from walking, which is sated 2 Hz. Two torque meters are used for friction measurement in rotational and sliding directions. Experiments simulated vertical vibration, rotary and reciprocating motion. Comparing friction coefficient with different substrates with SiNxHy film, mixture of PCL-PEG-PCL and bovine serum can effectively decrease friction but useless for mPEG-PCL-mPEG. If adhesion of PCL-PEG-PCL polymer can be improved, it has potential in the application of artificial joint.

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Nitone, Umesh, Jayaveersinh Mahida, and Seema Agrawal. "ONE-POT MCR REACTION VIA DIFFERENT BASE USED AS CATALYST ANDPEG-400 AS A SOLVENT." RASAYAN Journal of Chemistry 15, no. 04 (2022): 2761–66. http://dx.doi.org/10.31788/rjc.2022.1526815.

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Our motto for this work is green and natural resources use for the development of multicomponent reaction (MCRs) significant approach for the fabrication of polyfunctional molecules in an operatively easy and atom-economic manner, and the finding of novel MCRs appeal to various building blocks. Herein, the latest pyran-based phthalazinone pyrazole hybrids were synthesized by a facile one-pot MCR done by triethylamine, di-isopropyl ethyl amine (DIPEA), tripropylamine (TPA) as a catalyst. Check study led to the recognition of tripropylamine (TPA) with PEG-400 as the potential catalyst and green solvent, respectively, and the reusability of PEG-400 up to 5 cycles. This protocol opens a new perception for the introduction of rational design and the building blocks of MCRs.

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Tookalloo, Koorosh, Javad Heidarian, Mohammad Soleymani, Alimorad Rashidi, and Mahdi Nazarisaram. "Analyzing Effects of Multi-Wall Carbon Nanotubes (MWCNT) & Polyethylene Glycol (PEG) on Performance of Water Base Mud (WBM) in Shale Formation." Open Petroleum Engineering Journal 11, no. 1 (April 30, 2018): 29–47. http://dx.doi.org/10.2174/1874834101811010029.

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Background: Due to importance and unique properties of Multi-Wall Carbon Nanotube(s) (MWCNT), in the present study, effectiveness of these materials in Water Base Mud (WBM) is evaluated. Objective: The impacts of mud additives, local water and the addition of phases of bentonite and surfactants on the rheological properties, water loss and stability of water base mud in the absence of Multi-Wall Carbon Nanotube have been experimentally investigated. Materials and Methods: Then, the same experiment performed in the presence of Multi-Wall Carbon Nanotube to determine the efficiency and impact of Nanoparticles (NPs) on the properties of water base mud. The results have shown that additives, local water, Multi-Wall Carbon Nanotube dimensions, addition phase of bentonite and surfactants have influenced the rheological properties of the water base mud. Results: When Multi-Wall Carbon Nanotubes and polyethylene glycol alone or together are added, the performance terms of rheological properties decrease as by the subsequent order CNT; CNT + PEG; PEG. Multi-Wall Carbon Nanotube improves shale integrity and increases shale recovery. Conclusion: In general, the presence of Multi-Wall Carbon Nanotube increases the efficiency of polymers and rheological properties of the water base mud and eventually the shale stability is achieved.

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Wang, Jing-Lun, Liang-Nian He, Xiao-Yong Dou, and Fang Wu. "Poly(ethylene glycol): an Alternative Solvent for the Synthesis of Cyclic Carbonate from Vicinal Halohydrin and Carbon Dioxide." Australian Journal of Chemistry 62, no. 8 (2009): 917. http://dx.doi.org/10.1071/ch08554.

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Poly(ethylene glycol) (PEG) in this work proved to be an efficient reaction medium for the reaction of vicinal halohydrin with carbon dioxide in the presence of a base to synthesise cyclic carbonates. Notably, PEG-400 as an environmentally friendly solvent exhibits a unique influence on reactivity compared with conventional organic solvents. Various cyclic carbonates were prepared in high yield employing this protocol. The process presented here has potential applications in the industrial production of cyclic carbonates because of its simplicity, cost benefits, ready availability of starting materials, and mild reaction conditions.

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Gao, Pei-Sen, Kan Zhang, Ming-Ming Yang, Shan Xu, Hua-Ming Sun, Jin-Lei Zhang, Zi-Wei Gao, Wei-Qiang Zhang, and Li-Wen Xu. "A robust multifunctional ligand-controlled palladium-catalyzed carbonylation reaction in water." Chemical Communications 54, no. 40 (2018): 5074–77. http://dx.doi.org/10.1039/c8cc00324f.

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A novel and robust PEG-modulated s-triazine-based multifunctional and hydrophilic Schiff base/N,P-ligand L9 was employed in the Pd-catalyzed Heck-type carbonylative coupling reactions, yielding chalcone derivatives in good yields.

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Lan, Jiabo, Junru Shen, Linjie Dai, Tangxuan Wen, and Xiaoheng Zou. "Preparation of PH-sensitive drug delivery nanoparticles (PEG-Schiff base-Doxorubicin)." Emerging Science 1, no. 1 (2020): 127–34. http://dx.doi.org/10.47917/j.es.20190727.

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Saito, Hiroshi, Allan S. Hoffman, and Hiroaki Iyehara Ogawa. "Delivery of Doxorubicin from Biodegradable PEG Hydrogels Having Schiff Base Linkages†." Journal of Bioactive and Compatible Polymers 22, no. 6 (November 2007): 589–601. http://dx.doi.org/10.1177/0883911507084653.

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Chereches, Elena Ionela, and Alina Adriana Minea. "Experiments on the Electrical Conductivity of PEG 400 Nanocolloids Enhanced with Two Oxide Nanoparticles." Nanomaterials 13, no. 9 (May 5, 2023): 1555. http://dx.doi.org/10.3390/nano13091555.

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This paper aims to provide some insights into the pH and electrical conductivity of two classes of nanocolloids with PEG 400 as the base fluid. Thus, nanoparticles of two oxides—MgO and TiO2—were added to the base fluid in 5 mass concentrations in the range 0.25–2.5 %wt. The stability was evaluated in terms of pH at ambient temperature, while the electrical conductivity was discussed at both ambient temperature and up to 333.15 K. The electrical conductivity of PEG 400 was previously discussed by this group, while the behavior of the new nanocolloids was debated in terms of the state of the art. More precisely, the influence of MgO increases electrical conductivity, and an enhancement of up to 48% for 0.25% MgO was found, while the influence of TiO2 nanoparticles was found to be in similar ranges. In conclusion, electrical conductivity varies with temperature and the addition of nanoparticles to the base fluid, although the mechanisms that are driving the nanoparticle type and concentration influence are not yet entirely assumed in the available literature.

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Journal articles on the topic 'Tensioactifs à base de PEG'

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