Dialysis Recovery

Influence of Acid Type and Concentration on Diffusion Dialysis Recovery.975... 

Donnan dialysis Recovery of precious metals, softening of hard water, preconcentration of a trace amount of metal ions for analysis, etc. 

Open-ended 1-2 Nanoparticle separation Small-molecule separation Voltage-gated transport for transdermal drug deUvery Desalination Recovery of homogeneous catalysts Dialysis Recovery Stochastic sensing... 

The recovery of caustic from hemiceUulose (qv) ia the rayon process was well estabUshed ia the 1930s (18), and is still used ia modem times (19) (see Pulp). Very few new iadustrial appHcations of dialysis emerged duriag the 1940—1980 period. More recendy, iaterest has reawakened ia isobaric dialysis as a unit operation for the removal of alcohol from beverages (20,21) and ia the production of products derived from biotechnology (22,23). 

There is significant controversy over the role of loop diuretics in the treatment of ARE Theoretical benefits in hastening recovery of renal function include decreased metabolic oxygen requirements of the kidney, increased resistance to ischemia, increased urine flow rates that reduce intraluminal obstruction and filtrate backleak, and renal vasodilation.6 Theoretically, these effects could lead to increased urine output, decreased need for dialysis, improved renal recovery, and ultimately, increased survival. However, there are conflicting... 

With either type of dialysis, studies suggest that recovery of renal function is decreased in ARF patients who undergo dialysis compared with those not requiring dialysis. Decreased recovery of renal function may be due to hemodialysis-induced hypotension causing additional ischemic injury to the kidney. Also, exposure of a patient s blood to bioincompatible dialysis membranes (cuprophane or cellulose acetate) results in complement and leukocyte activation which can lead to neutrophil infiltration into the kidney and release of vasoconstrictive substances that can prolong renal dysfunction.26 Synthetic membranes composed of substances such as polysulfone, polyacrylonitrile, and polymethylmethacrylate are considered to be more biocompatible and would be less likely to activate complement. Synthetic membranes are generally more expensive than cellulose-based membranes. Several recent meta-analyses found no difference in mortality between biocompatible and bioincompatible membranes. Whether biocompatible membranes lead to better patient outcomes continues to be debated. 

GC, utilizing flame ionization detection (FID), has been used to measure diisopropyl methylphosphonate in meat, grain, or milk (Caton et al. 1994). Sample preparation steps include homogenization, filtration, dialysis, and extraction on a solid sorbent. Two common solid phase extractants, Tenax GC and octadecylsilane bonded silica gel (C18 Silica), were compared by Caton et al. (1994). They reported 70% recovery when using Tenax GC and 85% recovery when using C18 Silica. Sensitivity was not reported. Equilibrium experiments indicate that 8-10 mg of Tenax GC are required to achieve maximum recovery of each g of diisopropyl methylphosphonate (Caton et al. 1994). By extrapolating these... 

Mechanism-based inactivation results in formation of a covalent adduct between the active inhibitor and the enzyme, or between the active inhibitor and a substrate or cofactor molecule. If the mechanism involves covalent modification of the enzyme, then one should not be able to demonstrate a recovery of enzymatic activity after dialysis, gel filtration, ultrafiltration, or large dilution, as described in Chapters 5 to 7. Additionally, if the inactivation is covalent, denaturation of the enzyme should fail to release the inhibitory molecule into solution. If a radiolabeled version of the inactivator is available, one should be able to demonstrate irreversible association of radioactivity with the enzyme molecule even after denaturation and separation by gel filtration, and so on. In favorable cases one should likewise be able to demonstrate covalent association of the inhibitor with the enzyme by a combination of tryptic digestion and LC/MS methods. 

Fresh and frozen human tissue samples obtained from brain, liver, and kidney have been analyzed for hydrogen sulfide levels by sulfide-derived methylene blue determination using ion-interaction reversed-phase HPLC (Mitchell et al. 1993). This method can quantify nmol/g levels of sulfide. Gas dialysis/ion chromatography with ECD has been utilized for measurement of sulfide in brain tissue with 95-100% recovery (Goodwin et al. 1989). 

The successful of recovery of RNase A functional activity by a heat-induced AR method suggested the possibility of recovering RNase A immunoreactivity as well. The immunoreactivity of native RNase A and RNase A that was incubated at a concentration of 4 mg/mL in 10% neutral buffered formalin for 1 day and then freed of formaldehyde by dialysis against PBS was compared using capture enzyme-linked immunosorbent assay (ELISA). Selected fractions that... 

Remove excess crosslinker and reaction by-products by dialysis or size exclusion chromatography. For small quantities of bait proteins, dialysis may be the better choice, because gel filtration columns often bind nonspecifically enough protein to make recoveries unacceptably low. 

At plasma nickel concentrations of about 3 mg/L, patients had adverse effects including headaches, nausea, vomiting, and weakness recovery occurred 3 to 13 h after cessation of dialysis... 

Lantagne and Velin [267] have reviewed the application of dialysis, electrodialysis and membrane cell electrolysis for the recovery of waste acids. Because of the new trends governed by environmental pressures, conventional treatment methods based on neutralization and disposal are being questioned. Membrane and electromembrane technologies are considered to be potential energy-efficient substitutes for conventional approaches. Paper mills will focus on the application of ion-exchange membranes namely dialysis, electrodialysis and membrane cell electrolysis for recovery of waste acids. 

Lantagne G, Velin AP, Overview of the application of dialysis, electrodialysis and membrane cell electrolysis for the recovery of waste acids, in ref (45a), and references therein... 

Membrane-Enclosed Enzymatic Catalysis (MEEC) has been developed as a useful, practical new method for the manipulation of enzymes in organic synthesis. The enzyme in soluble form is enclosed in commercially available dialysis membranes. It combines the simplicity of use of soluble enzymes with certain of the advantages of immobilized enzymes. Containment permits separation of the enzyme from the reaction medium, straightforward separation of the product, and recovery of the enzyme for reuse [53],... 

A (rapidly) reversible inhibitor will permit rapid and complete recovery of enzyme activity by dialysis. However, irreversible inhibitors are not removed by this procedure. Recovery from tight-binding inhibition is usually slow it is not uncommon for several dialysis bags containing enzyme to be prepared and for activity in each to be determined at various time points following the commencement of dialysis. The off-rate of these inhibitors is generally more rapid at higher temperatures. 

The same hyperbranched polyglycerol modified with hydrophobic palmitoyl groups was used for a noncovalent encapsulation of hydrophilic platinum Pincer [77]. In a double Michael addition of ethyl cyanoacetate with methyl vinyl ketone, these polymer supports indicated high conversion (81 to 59%) at room temperature in dichloromethane as a solvent. The activity was stiU lower compared with the noncomplexed Pt catalyst. Product catalyst separation was performed by dialysis allowing the recovery of 97% of catalytic material. This is therefore an illustrative example for the possible apphcation of such a polymer/catalyst system in continuous membrane reactors. 

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