Ionics, Inc.

The Hubinger Co.

Surendar M Jain

Anthony J Giuffrida

Kalyanasundram Venkatasubramanian

Kalyanasundram Venkatsubramanian

A polarity reversing electrodialysis membrane stack containing a composite electrode at each end of the stack with each electrode having anode and cathode portions electrically insulated from each other. Current is supplied to the anode portion of one electrode and to the cathode portion of the other electrode with means for maintaining a trickle of current from the active anode of one electrode to the inactive anode of the other electrode. Upon reversal of stack polarity the electrodes change their polarities and the trickle currents runs to the other electrode. The invention also is directed to the use of noble metal coated electrodes wherein the coating covers substantially less than the total electrode surface which is in contact with electrolytic solution during use.

Polarity reversal electrodes

A process and apparatus for treating a liquid protein mixture is disclosed in which the protein mixture is first demineralized by electrodialysis (ED) and then subjected to isoelectric focusing (IEF) to effect the separation of proteins based on differences in their isoelectric points (pI). This combination of ED-IEF results in an improved separation of the protein components of a mixture than without the ED step.

Separation of proteins using electrodialysis - isoelectric focusing

A process is described for the selective recovery and/or concentration of a protein or a class of proteins from fermentation broth employing a combination of desalting and pH adjustment thereby causing the initial precipitation of unwanted proteins, again subjecting the resulting supernatant to another set of pH adjustment and desalting to cause the protein of interest to precipitate thereby obtaining a highly enriched fraction of the selected protein. Such a process will find use in the specific recovery of genetically engineered proteins from fermentation broths, e.g. interferon, insulin, growth hormone, etc.

Selected recovery of proteins from fermentation broths

A process and apparatus for treating a liquid protein mixture is disclosed in which the protein mixture is first determined by electrodialysis (ED) and then subjected to isoelectric focusing (IEF) to effect the separation of proteins based on differences in their isoelectric points (pI). This combination of ED-IEF results in an improved separation of the protein components of a mixture than without the ED step.

Separation of proteins using electrodialysis-isoelectric focusing

This invention describes the process of separating dextrose preferentially from a mixture of dextrose and oligosaccharides by using ion exchange membranes. More particularly it relates to the process comprising the steps of (1) passing a liquid mixture of dextrose and oligosaccharides through a first feed chamber of an electro-osmosis cell comprising at least two chambers defined between ion exchange membranes having alternating high and low permeability coefficients with respect to each other, (2) passing a direct electric current transversely through said membranes and chambers in a direction to cause the dextrose to pass from said feed chamber through said high permeability coefficient membrane into a second chamber with said dextrose being substantially retained in the second chamber, and (3) recovering an oligosaccharide enriched and a dextrose enriched effluent from the separate chambers.

Process for the preferential separation of dextrose from oligosaccharides

This invention relates to the separation of complex protein mixtures by lowering (desalting) or by raising (salting-out) their electrolytic (ionic) concentration by electrodialysis followed by chilling, pH adjustment, filtration, and/or centrifugation and optionally thereafter restoration of the lost electrolyte or removal of the gained electrolyte and water. This technique is especially adaptable for therapeutic plasma exchange performed in situ for immunepheresis i.e. removal of globulin or immunecomplexes implicated in autoimmune diseases. The techniques are also applicable for antihemophilic factor separation and purification, and separation of proteins from whey.

Fractionation of protein mixtures

A process is described for the fractionation of solutions of protein mixtures which includes the steps of subjecting such solutions to 'salting-out', separation of the resulting turbidity, subsequent removal of the 'salting-out' agent from the supernatant by dialysis and finally making up the original salt level of the liquid if required. Such a process may be used in therapeutic plasma exchange where removal of immunoglobulins or their complexes therefrom is desired so that the remaining albumin void of immunoglobulins can be administered back to the patient.

Fractionation of protein mixtures by salt addition followed by dialysis

This invention describes the process of separating fructose preferentially from a mixture of glucose and fructose by using ion exchange membranes. More particularly it relates to the process comprising the steps of (1) passing a liquid mixture of fructose and glucose through a first feed chamber of an electro-osmosis cell comprising at least two chambers defined between ion exchange membranes having alternating high and low permeability coefficients with respect to each other, (2) passing a direct electric current transversely through said membranes and chambers in a direction to cause the fructose to pass from said feed chamber through said high permeability coefficient membrane into a second chamber with said fructose being substantially retained in the second chamber, and (3) recovering a glucose enriched and a fructose enriched effluent from the separate chambers.

Process for the preferential separation of fructose from glucose

Apparatus and process for the fractionation of liquid solutions of protein mixtures which includes the steps of subjecting such solutions to electrodialysis (ED) while in the pH range of about between 5-8 until a partial or a substantially complete desalting takes place, the ED preferably being conducted between about 15.degree. C. to 40.degree. C., separating the fraction of protein which precipitates, passing the resulting supernatant salt depleted protein mixture into the concentrating compartments of the ED apparatus whereby the salts entering the salt concentrating chambers from the adjacent salt diluting chambers will substantially restore the original salt content of the desalted protein mixture.

Growing community of inventors

Watertown, MA, United States of America

Surendar M Jain