High-Flux Cellulose Acetate Membranes

One major goal of dialysis therapy has become the removal of ß2-microglobulin (ß2-m). The interdialytic elimination of ß2-m was studied using a newly developed high-flux cellulose acetate (CA) membrane. The results show that high-flux CA dialyzers offer better biocompatibility than classical Cuprophan or high-flux Cuprophan devices, with regard to leukopenia, C3a desarg generation, and elastase release from polymorphonuclear (PMN) leukocytes. Compared to high-flux CA membranes, high-flux PMMA membranes induce less C3a desarg formation but comparable leukopenia. High-flux PMMA membranes, however cause greater leukocyte stimulation than CA as demonstrated by more PMN elastase release during hemodialysis. Using high-flux CA or high-flux PMMA membranes, serum ß2-m levels decreased 32% during dialysis. Serum ß2-m dropped 10% with high-flux Cuprophan membranes, but remained unchanged with conventional Cuprophan dialyzers. Sieving coefficients for ß2-microglobulin (ß2-m) were virtually zero with classical Cuprophan and 0.66 with high-flux cellulose acetate membranes. High-flux membranes made of Cuprophan and PMMA gave coefficients of 0.25 and 0.45, respectively. This indicates the high removal capacity of the new CA-membrane for substances with high molecular weight. This high-flux CA membrane thus appears to combine a good degree of biocompatibility with a high capacity for ß2-m removal.

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Immunoextraction of CD25 Using Anti-CD25 Monoclonal Antibodies in Artificial Kidneys

Journal of Biomimetics Biomaterials and Tissue Engineering ◽

10.4028/www.scientific.net/jbbte.9.93 ◽

2011 ◽

Vol 9 ◽

pp. 93-99

Author(s):

Michael L. Branham

Keyword(s):

Cellulose Acetate ◽

In Vitro Model ◽

Interleukin 2 ◽

High Flux ◽

Cellulose Acetate Membranes ◽

Artificial Kidneys ◽

Soluble Interleukin 2 Receptor ◽

Vitro Model ◽

Antigen Antibody

The objectives of this study were to compare transport characteristics of the soluble interleukin-2 receptor (CD25) in haemodialyzers (high- and low flux) under equilibrium and sink conditions. Using an in vitro model high-flux polymethylmethacrylate (PMMA), high-flux cellulose acetate (CA), and low-flux polysulfone (PSF) dialyzer membranes were perfused with CD25 through the intracapillary space. Anti-CD25 antibodies added to the extracapillary space resulted in immunoextraction of CD25 after the system had reached steady-state. Results indicate that CD25 was efficiently cleared by both high-flux dialyzers but not the low-flux dialyzer. Furthermore, CD25 interaction with cellulose acetate membranes may promote formation of antigen-antibody lattice structures which disperse after antigen concentrations occur in excess. CD25 did not strongly adsorb to any of the membranes but its mass clearance was significantly enhanced by antibodies in the dialysate compartment. These studies demonstrated the utility of in vitro experiments to elucidate midsize molecule clearance during dialysis therapy.

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Effect of the structure of cellulose acetate membranes on their permeability, electrical conductivity and rejection

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902933 ◽

1990 ◽

Vol 55 (12) ◽

pp. 2933-2939 ◽

Cited By ~ 1

Author(s):

Hans-Hartmut Schwarz ◽

Vlastimil Kůdela ◽

Klaus Richau

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Cellulose Acetate ◽

Reverse Osmosis ◽

Water Flux ◽

Cellulose Acetate Membrane ◽

Structure Parameters ◽

Dc Electrical Conductivity ◽

Cellulose Acetate Membranes

Ultrafiltration cellulose acetate membrane can be transformed by annealing into reverse osmosis membranes (RO type). Annealing brings about changes in structural properties of the membranes, accompanied by changes in their permeability behaviour and electrical properties. Correlations between structure parameters and electrochemical properties are shown for the temperature range 20-90 °C. Relations have been derived which explain the role played by the dc electrical conductivity in the characterization of rejection ability of the membranes in the reverse osmosis, i.e. rRO = (1 + exp (A-B))-1, where exp A and exp B are statistically significant correlation functions of electrical conductivity and salt permeation, or of electrical conductivity and water flux through the membrane, respectively.

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Transport properties of Toray's asymmetric cellulose acetate membranes

Desalination ◽

10.1016/0011-9164(85)85029-3 ◽

1985 ◽

Vol 56 ◽

pp. 251-260 ◽

Cited By ~ 3

Author(s):

M. Kurihara ◽

W. Pusch ◽

T. Tanaka

Keyword(s):

Transport Properties ◽

Cellulose Acetate ◽

Cellulose Acetate Membranes

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Quantitative alkaline phosphatase isoenzyme determination by electrophoresis on cellulose acetate membranes.

Clinical Chemistry ◽

10.1093/clinchem/23.1.28 ◽

1977 ◽

Vol 23 (1) ◽

pp. 28-34 ◽

Cited By ~ 19

Author(s):

W H Siede ◽

U B Seiffert

Keyword(s):

Alkaline Phosphatase ◽

Cellulose Acetate ◽

Clinical Laboratory ◽

Kinetic Assay ◽

Specific Staining ◽

Cellulose Acetate Membranes ◽

Alkaline Phosphatase Isoenzymes ◽

Elution Method ◽

Routine Clinical Laboratory ◽

Alkaline Phosphatase Isoenzyme

Abstract We present a new method for quantitative determination of alkaline phosphatase isoenzymes. This method consists of electrophoretic separation on cellulose acetate membranes, special fixation technique to avoid elution and diffusion of enzyme protein during incubation, specific staining, and quantitative evaluation by densitometric measurement. We highly recommend the precedure for routine clinical laboratory use. In all normal individuals we observe two isoenzymes of hepatic origin and one isoenzyme each of osseous, intestinal, and biliary origin. Quantitative normal values are presented. Precision of the method is calculated, the CV being less than 10%. The exactness of densitometric quantification is proved by comparison with kinetic assay of alkaline phosphatase isoenzymes by use of an elution method. Clinical implications of alkaline phosphatase isoenzymograms are reported and discussed in detail.

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