Described herein is a method of purifying a target molecule from an aqueous biological composition, the method comprising: (a) contacting a cationic polymer and the aqueous biological composition to form a mixture, the mixture comprising a bio-polymer complex and the target non-binding molecule in a liquid, wherein the bio-polymer complex has an average particle diameter of at least 50 micrometers; (b) providing a filtering unit comprising (i) a housing having an inlet and an outlet, (ii) a porous, continuous filter medium which is fluidly connected to the inlet and the outlet, and (iii) a collection region upstream from the porous, continuous filter medium; (c) adding the mixture to the inlet; and (d) allowing the mixture to separate in the filtering unit, whereby the bio-polymer complex collects in the collection region and the target non-binding molecule passes through the filter medium, and wherein the majority of flow of the liquid through the porous, continuous filter medium is not substantially parallel with the direction of gravity.

Described herein is a method of purifying a target molecule from an aqueous biological composition, the method comprising: (a) contacting a cationic polymer and the aqueous biological composition to form a mixture, the mixture comprising a bio-polymer complex and the target non-binding molecule in a liquid, wherein the bio-polymer complex has an average particle diameter of at least 50 micrometers; (b) providing a filtering unit comprising (i) a housing having an inlet and an outlet, (ii) a porous, continuous filter medium which is fluidly connected to the inlet and the outlet, and (iii) a collection region upstream from the porous, continuous filter medium; (c) adding the mixture to the inlet; and (d) allowing the mixture to separate in the filtering unit, whereby the bio-polymer complex collects in the collection region and the target non-binding molecule passes through the filter medium, and wherein the majority of flow of the liquid through the porous, continuous filter medium is not substantially parallel with the direction of gravity.

In certain embodiments, the invention provides a method of purifying a protein of interest from a mixture which comprises the protein of interest and one or more contaminants, comprising: a) subjecting the mixture to a first chromatography step; b) recovering the protein of interest in an elution solution; c) adding caprylic acid to the elution solution to form a contaminant precipitate; d) removing the contaminant precipitate from the elution solution; and e) subjecting the post-precipitated elution solution to a second chromatography column, thereby purifying the protein of interest.

In certain embodiments, the invention provides a method of purifying a protein of interest from a mixture which comprises the protein of interest and one or more contaminants, comprising: a) subjecting the mixture to a first chromatography step; b) recovering the protein of interest in an elution solution; c) adding caprylic acid to the elution solution to form a contaminant precipitate; d) removing the contaminant precipitate from the elution solution; and e) subjecting the post-precipitated elution solution to a second chromatography column, thereby purifying the protein of interest.

For the removal of high molecular weight compounds from recombinantly produced polypeptides generally chromatographic methods are employed. It has been found that underivatized controlled pore glass (uCPG) selectively binds high molecular weight compounds present in a solution. The purified polypeptide can be recovered e.g. from the flow through of a chromatography column containing uCPG as chromatography material. It has been found that this effect is pronounced at a pH value of about 4 to 6 in buffered solutions. With approximately 100 m.sup.2 to 150 m.sup.2 uCPG surface per g of polypeptide almost 80% to 95% of the high molecular weight compounds are removed with a yield of 80% to 90% of polypeptide.

For the removal of high molecular weight compounds from recombinantly produced polypeptides generally chromatographic methods are employed. It has been found that underivatized controlled pore glass (uCPG) selectively binds high molecular weight compounds present in a solution. The purified polypeptide can be recovered e.g. from the flow through of a chromatography column containing uCPG as chromatography material. It has been found that this effect is pronounced at a pH value of about 4 to 6 in buffered solutions. With approximately 100 m.sup.2 to 150 m.sup.2 uCPG surface per g of polypeptide almost 80% to 95% of the high molecular weight compounds are removed with a yield of 80% to 90% of polypeptide.

The present invention relates to method for purifying proteins using silicates.

The present invention relates to method for purifying proteins using silicates.

A method includes enriching biomolecules and removal of the biomolecules from a biological sample. In the presence of particles, an alginate solution and salts of divalent and/or polyvalent cations or an acid are added to a biological sample, and an alginate-gel-biomolecule-complex is formed on the particles. The complex is removed from the sample by separation of the particles, and from which subsequently the biomolecules or ingredients of the biomolecules are released. The biomolecules, which shall be enriched, include cell-free nucleic acids, viruses or subcellular microparticles. The method is improved and simplified.

A protein construct including a gene encoding a light-sensitive protein fused to at least one of either a low complexity sequence, an intrinsically disordered protein region (IDR), or a repeating sequence of a linker and another gene encoding a light-sensitive protein. Among the many different possibilities contemplated, the protein construct may also advantageously include cleavage tags. This protein construct may be utilized for a variety of functions, including a method for protein purification, which requires introducing the protein construct into a living cell, and inducing the formation of clusters by irradiating the construct with light. The method may also advantageously include cleaving a target protein from an IDR, and separating the clusters via centrifuge. A kit for practicing in vivo aggregation or liquid-liquid phase separation is also included, the kit including the protein construct and a light source capable of producing a wavelength that the light-sensitive protein will respond to.