Liquid purification or separation – Processes – Liquid/liquid solvent or colloidal extraction or diffusing...
Patent
1984-10-26
1986-04-01
Adee, John
Liquid purification or separation
Processes
Liquid/liquid solvent or colloidal extraction or diffusing...
210638, 210927, B01D 1508
Patent
active
045796610
DESCRIPTION:
BRIEF SUMMARY
The present invention is concerned with a process in the purification of a biologically active substance with the aid of a system of at least two immiscible aqueous phases.
When a solution contains biologically active substances such as for example peptides, proteins and other biomolecules it is desirable to have ways and means for isolating individual components therefrom, and consequently a major number of separation methods have been developed for various different systems of biomolecules. For large-scale separations, a number of techniques employing columns are now being used extensively. In these methods the solution is passed along a gel bed; in passing along the bed the individual components present in the solution will be delayed in different degrees, depending on their molecular size (gel filtration), or will bind to groups present in the gel, depending on electric charge (ion exchange chromatography), or will bind due to biospecific affinity to ligands immobilized in the gel (affinity chromatography). These methods often require long separation times since the amount of solution to be passed through the column is relatively large, and moreover the range of practical applicabilities of such methods will be limited because of the requirement that all components should be present in a solubilized form; for if solids are present these will greatly tend to obturate the gel bed. Therefore, if any such non-dissolved material is present in a biological fluid sample an extra preliminary separation step is required, such as e.g. filtration and/or centrifugation.
A method found to have potential advantages in connection with large-scale purifications involves the utilization of systems containing at least two liquid phases having different polar properties, in which case different components of the sample assume different patterns inter se of their respective distribution among the phases. In view of the fact that biological substances often require mild conditions of treatment in order to avoid losing their activity the phases employed are in the first place aqueous phases, sometimes in conjunction with mild organic solvents.
Separation systems of this type may contain aqueous solutions of
Systems according to item (1) consisting of at least two aqueous polymers have been described by for example Albertsson, P. A., in "Partition of Cell Particles and Macromolecules" (Almquist & Wiksell, Stockholm, and John Wiley & Sons Inc., New York 1971); in addition to water such systems may contain for example the following combinations of water-soluble polymers: polyethylene glycol/dextran; polypropylene glycol/dextran; polyethylene glycol/polyvinyl alcohol; polyethylene glycol/Ficoll.RTM. (copolymer of sucrose and epichlorohydrin, from Pharmacia Fine Chemicals, Uppsala, Sweden); polyvinyl alcohol/dextran; methyl cellulose/dextran; polypropylene glycol/polyvinyl pyrrolidone; charged polyethylene glycol/dextran; polypropylene glycol/methoxypolyethylene glycol; polypropylene glycol/polyvinyl alcohol; polypropylene glycol/hydroxypropyl dextran; polyethylene glycol/polyvinyl pyrrolidone; polyethylene glycol/starch; and polyvinyl alcohol/methyl cellulose. Additional combinations of these and also other polymers are well known from the literature. Among the aforesaid combinations, the two-phase systems comprising dextran as their more polar phase have been studied most extensively; but the comparatively high price of dextran is a limiting factor for the large-scale utilization of the method.
In systems according to the above item (2) containing aqueous solutions of at least one polymer and at least one salt, the polymer may be selected from among those mentioned above and the salt may be a water-soluble organic or inorganic salt such as e.g. phosphate or sulfate, for example potassium phosphate and magnesium sulfate. The more polar phase which in this case is a salt solution can be prepared at low costs, so this method will be well suited for economically attractive large-scale applications.
As can be seen from item (3) abo
REFERENCES:
patent: 3996132 (1976-12-01), Mateos et al.
patent: 4207200 (1980-06-01), Muller et al.
patent: 4268395 (1981-05-01), Stewart
patent: 4406865 (1983-09-01), Fuller
patent: 4464165 (1984-08-01), Pollard, Jr.
Chemical Abstracts, vol. 78, 1983, p. 188, No. 120936s.
Gustafsson Sture J.
Hedman Per O.
Ling Torbjorn G. I.
Mattiasson Bo G.
Adee John
Pharmacia AB
Philpitt Fred
LandOfFree
Process in the purification of biologically active substances does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process in the purification of biologically active substances, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process in the purification of biologically active substances will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1083440