Albumin denaturation during ultrafiltration: Effects of operating conditions and consequences on membrane fouling

Meireles, Martine; Aimar, Pierre; Sánchez, V.

doi:10.1002/bit.260380511

Cited by 138 publications

(75 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Existing shear devices generate other stresses including surface interactions and enhanced protein-air contacts, which complicates data interpretation. 121,132,133 However, it has been established that the shear-stability of a protein molecule depends on: (i) its primary structure and molecular weight (ii) the magnitude of shear strain and the duration of its application, and (iii) the viscosity of its surrounding medium. 31,64,65 Therefore, these factors must be taken in consideration for a complete understanding of the shear-stability of protein systems.…”

Section: Implications In Physiology and Bioprocessingmentioning

confidence: 99%

The effects of shear flow on protein structure and function

Bekard

Asimakis

Bertolini³

et al. 2011

Biopolymers

148

140

View full text Add to dashboard Cite

Toxoplasma gondii usually causes an asymptomatic and then latent infection in human adults; however, a potentially fatal disseminated form can occur in immunocompromised patients. Given that the diagnosis of acute Toxoplasma infection, as opposed to latent disease, relies on finding direct evidence of T. gondii infection in tissue, pathologic examination is critical. There have only been a few reports describing the cytomorphology of Toxoplasma in exfoliative cytology, and no reports of the findings in Thin Prep. In this report, we describe a fatal case of toxoplasmosis in a cardiac transplant patient that was diagnosed by respiratory cytopathology. Although the extracellular organisms were well visualized on the Wright‐Giemsa stained cytospin, they were only faintly seen on the Pap‐stained cytospin trapped within mucin and were not easily appreciated on the ThinPrep slides nor the H&E stained cell block sections. An immunohistochemical stain for Toxoplasma performed on the cell block was strongly positive, and an autopsy performed on the patient confirmed disseminated infection. Our case illustrates that the diagnosis of Toxoplasma in exfoliative cytology specimens can be challenging since organisms are not well visualized on ThinPrep or Pap‐stained material; therefore, Wright‐Giemsa stained material can be particularly helpful. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.

show abstract

Section: Implications In Physiology and Bioprocessingmentioning

confidence: 99%

The effects of shear flow on protein structure and function

Bekard

Asimakis

Bertolini³

et al. 2011

Biopolymers

148

140

View full text Add to dashboard Cite

show abstract

“…hydrophilicity) on fouling behavior, it was necessary to measure the following¯uxes (the same coupons were used through steps 1 to 4): 1. J 0 , the initial electrolyte solution¯ux after 10 h of membrane compaction at 3.6 bar and 283 K. All experiments were performed at this temperature due to investigations by Meireles et al [23] who determined a critical operating temperature below which pump shear-induced albumin denaturation would become negligible. Preliminary experiments revealed that¯ux reduction due to pressure-induced compaction of the membrane occurred within the ®rst few hours to the most signi®cant extent.…”

Section: Fouling Experimentsmentioning

confidence: 99%

Static protein adsorption, ultrafiltration behavior and cleanability of hydrophilized polysulfone membranes

Möckel

Staude

Guiver

1999

Journal of Membrane Science

166

View full text Add to dashboard Cite

A systematic study on the in¯uence of incrementally increased hydrophilicity of UF membranes made from chemically modi®ed polysulfone on static protein adsorption, protein ultra®ltration performance and cleanability was performed. Hydrophilicity was imparted to the polymeric backbone either by carboxylation or sulfonation. Membranes with 100% retention towards sulfhydryl modi®ed bovine serum albumin (cys-BSA) were made by the phase inversion process from unmodi®ed polysulfone, ®ve carboxylated polysulfones (degrees of carboxylation ranging from 0.26 to 1.74) and two sulfonated polysulfones (degrees of sulfonation of 0.24 and 0.58). 1000 ppm aqueous solutions of cys-BSA at pH values 3, 4.8 and 9 were used in KCl medium at either low or high concentration. Static adsorption, ultra®ltration (UF)¯ux reduction and protein binding strength were lower at pH 3 than at pH 9 but reached an expected maximum at the protein's isoelectric point at pH 4.8. Hydrophilized polysulfone membranes show less static adsorption and lower UF¯ux reduction than hydrophobic unmodi®ed membranes. In all experiments we found that the higher the degree of carboxylation or sulfonation, the greater this effect. High ionic strengths reduced these advantages at pH values above or below the IEP but had a positive effect at the IEP. #

show abstract

“…Quelques phénomènes ont ainsi pu être mis en évidence en microfiltration et en ultrafiltration tels que l'effet du cisaillement, de la température et de la concentration sur la susceptibilité de certaines protéines à s'adsorber ou à former des agrégats (Meireles et al, 1991 ;Bowen et Gan, 1991a, b et 1992Kim et al, 1993). On trouve peu d'études tentant de mettre en évidence ces mêmes phénomènes dans des systèmes complexes tels que les fluides laitiers (Gésan, 1993).…”

unclassified

Microfiltration de lactosérum doux sur membranes d'alumine : influence des conditions hydrodynamiques sur le colmatage

Pouliot

Britten³

et al. 1995

Lait

View full text Add to dashboard Cite

Résumé -Il est possible de caractériser le colmatage d'un microfiltre par l'évaluation de la résistance hydraulique décomposée en une série de résistances partielles en cours de microfiltration. Différentes conditions hydrodynamiques (4 pressions transmembranaires et 3 vitesses tangentielles) ont été étu-diées lors de la microfiltration de lactosérum pour vérifier leur effet sur le colmatage et la rétention protéique d'un système à 4 membranes de microfiltration en alumine (Ceraflo, 0,221lm de diamètre de pore) montées en série. Le colmatage total a été significativement affecté par la pression transmembranaire, le facteur de concentration volumique et la vitesse tangentielle. La pression transmembranaire a constitué le facteur le plus important. La rétention (cr) de la sérum albumine bovine était totale, la~-lactoglobuline était retenue à >0,55 et l'a-lactalbumine à 0,40 dès le début de la filtration. La rétention était surtout affectée par la pression transmembranaire et la concentration des solutés et très peu par la vitesse tangentielle. La géométrie du filtre et les résultats expérimentaux suggèrent que le colmatage se situe surtout à l'intérieur de la matrice microporeuse à cause de la forte influence de la pression transmembranaire et de la faible influence de la vitesse tangentielle. Le colmatage serait dû à la déposition d'agrégats protéiques sous l'effet dénaturant des forces de cisaillement.

show abstract

Albumin denaturation during ultrafiltration: Effects of operating conditions and consequences on membrane fouling

Cited by 138 publications

References 10 publications

The effects of shear flow on protein structure and function

The effects of shear flow on protein structure and function

Static protein adsorption, ultrafiltration behavior and cleanability of hydrophilized polysulfone membranes

Microfiltration de lactosérum doux sur membranes d'alumine : influence des conditions hydrodynamiques sur le colmatage

Contact Info

Product

Resources

About