A simple procedure for removing contaminating aldehydes and peroxides from aqueous solutions of polyethylene glycols and of nonionic detergents that are based on the polyoxyethylene linkage

Ray, William J.; Puvathingal, Joseph M.

doi:10.1016/0003-2697(85)90544-5

Cited by 77 publications

(45 citation statements)

References 5 publications

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“…The present polyethylene glycol chains do not contain charged functional groups and the zeta potential of −45 mV at pH 7 is explained by the adsorbed hydroxide ions. However, compared to the pristine membrane, the IEP is slightly more acidic, what can be explained by small amounts of negatively charged functional groups which are present on the membrane surface and originate either from oxidation during irradiation or from oxidized impurities in the used PEG [52,53]. Nevertheless, when compared to the PVDF-PSS membrane it becomes clear that no additional negatively charged groups were added to the membrane surface.…”

Section: Characteristics Of Modified Pvdf Membranesmentioning

confidence: 96%

Tailoring Membrane Surface Charges: A Novel Study on Electrostatic Interactions during Membrane Fouling

et al. 2015

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Abstract:In this work we aim to show that the overall surface potential is a key factor to understand and predict anti-fouling characteristics of a polymer membrane. Therefore, polyvinylidene fluoride membranes were modified by electron beam-induced grafting reactions forming neutral, acidic, alkaline or zwitterionic structures on the membrane surface. The differently charged membranes were investigated regarding their surface properties using diverse analytical methods: zeta potential, static and dynamic water contact angle, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Porosimetry measurements proved that there is no pore blocking due to the modifications. Monodisperse suspensions of differently charged polystyrene beads were synthesized by a radical emulsion polymerization reaction and were used as a model fouling reagent, preventing comparability problems known from current literature. To simulate membrane fouling, different bead suspensions were filtered through the membranes. The fouling characteristics were investigated regarding permeation flux decline and concentration of model fouling reagent in filtrate as well as by SEM. By considering electrostatic interactions equal to hydrophobic interactions we developed a novel fouling test system, which enables the prediction of a membrane's fouling tendency. Electrostatic forces are dominating, especially when charged fouling reagents are present, and can help to explain fouling characteristics that cannot be explained considering the surface wettability.

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Section: Characteristics Of Modified Pvdf Membranesmentioning

confidence: 96%

Tailoring Membrane Surface Charges: A Novel Study on Electrostatic Interactions during Membrane Fouling

et al. 2015

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“…Better crystals came with high purity commercial PEGs (Fluka or Hampton Research Inc.). but not with additional PEG purification (Ray & Puvathingal, 1985;Jurnak, 1986). Crystals were obtained at pH 7.5 and with 10 to 20 mg/mL protein at either 4 or 20°C.…”

Section: Purification Of a K From A Natural Source (Horseshoe Crabs) mentioning

confidence: 99%

Expression, purification from inclusion bodies, and crystal characterization of a transition state analog complex of arginine kinase: A model for studying phosphagen kinases

et al. 1997

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Phosphagen kinases catalyze the reversible transfer of a phosphoryl group between guanidino phosphate compounds and ADP, thereby regenerating ATP during bursts of cellular activity. Large quantities of highly pure arginine kinase (EC 2.7.3.3), the phosphagen kinase present in arthropods, have been isolated from E. coli, into which the cDNA for the horseshoe crab enzyme had been cloned. Purification involves size exclusion and anion exchange chromatographies applied in the denatured and refolded states. The recombinant enzyme has been crystallized as a transition state analog complex. Near complete native diffraction data have been collected to 1.86 A resolution. Substitution of a recombinant source for a natural one, improvement in the purification, and data collection at cry0 temperatures have all yielded significant improvements in diffraction. This reaction and those of the rest of the guanidino (or phosphagen) kinase family, including creatine kinase (CK), enable ATP to be quickly regenerated from storage phosphagens during bursts of cellular activity. In addition to this "temporal" buffering, it has been proposed that these enzymes also function in "spatial" buff-

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“…The chemicals were purchased from indicated source: EDTA (Sigma), LDAO (Fluka), ß-OG (Bachern), PEG (Merck, purified according to [21]), NaN 3 , NaCl and Tris (Merck).…”

Section: Chemicals and Materialsmentioning

confidence: 99%

Solubility diagram of theRhodobacter sphaeroidesreaction center as a function of PEG concentration

Gaucher¹,

Riès-Kautt²,

Reiss‐Husson³

et al. 1997

FEBS Letters

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A simple procedure for removing contaminating aldehydes and peroxides from aqueous solutions of polyethylene glycols and of nonionic detergents that are based on the polyoxyethylene linkage

Cited by 77 publications

References 5 publications

Tailoring Membrane Surface Charges: A Novel Study on Electrostatic Interactions during Membrane Fouling

Tailoring Membrane Surface Charges: A Novel Study on Electrostatic Interactions during Membrane Fouling

Expression, purification from inclusion bodies, and crystal characterization of a transition state analog complex of arginine kinase: A model for studying phosphagen kinases

Solubility diagram of theRhodobacter sphaeroidesreaction center as a function of PEG concentration

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