The preparation method of a starch-based double-loaded functional nanoparticle includes: performing restrictive hydrolysis treatment on egg high-density lipoprotein using proteases to obtain the polypeptide; performing self-assembling on a mixed system containing the polypeptide and quercetin under the alkaline condition to form a micelle nanoparticle; performing covalent grafting reaction on a mixed system containing the micelle nanoparticle and anthocyanin under the alkaline condition to form a graft; and electrostatically compounding carboxymethyl dextrin with the graft to obtain the starch-based double-loaded functional nanoparticle. In the preparation method, raw materials derived from natural sources are used, and the self-assembled colloid nanoparticle with good properties can be obtained by adjusting the pH without any organic reagents. The obtained product has a nanoparticle size, has high antioxidant activity and stability against environmental stress, and can be widely applied to the fields of delivery of nutrients, stabilization of biologically active substances and the like.

The present invention concerns a method of storing a separation matrix comprising multimers of immunoglobulin-binding alkali-stabilized Protein A domains covalently coupled to a porous support. The method comprises the steps of: a) providing a storage liquid comprising at least 50% by volume of an aqueous alkali metal hydroxide solution; b) permeating the separation matrix with the storage liquid; and c) storing the storage liquid-permeated separation matrix for a storage time of at least days. The alkali-stabilized Protein A domains comprise mutants of a parental Fc-binding domain of Staphylococcus Protein A (SpA), as defined by, or having at least 80% such as at least 90%, 95% or 98% identity to, SEQ ID NO 51 or SEQ ID NO 52, wherein the amino acid residues at positions 13 and 44 of SEQ ID NO 51 or 52 are asparagines and wherein at least the asparagine residue at position 3 of SEQ ID NO 51 or 52 has been mutated to an amino acid selected from the group consisting of glutamic acid, lysine, tyrosine, threonine, phenylalanine, leucine, isoleucine, tryptophan, methionine, valine, alanine, histidine and arginine.

The present invention concerns a method of storing a separation matrix comprising multimers of immunoglobulin-binding alkali-stabilized Protein A domains covalently coupled to a porous support. The method comprises the steps of: a) providing a storage liquid comprising at least 50% by volume of an aqueous alkali metal hydroxide solution; b) permeating the separation matrix with the storage liquid; and c) storing the storage liquid-permeated separation matrix for a storage time of at least days. The alkali-stabilized Protein A domains comprise mutants of a parental Fc-binding domain of Staphylococcus Protein A (SpA), as defined by, or having at least 80% such as at least 90%, 95% or 98% identity to, SEQ ID NO 51 or SEQ ID NO 52, wherein the amino acid residues at positions 13 and 44 of SEQ ID NO 51 or 52 are asparagines and wherein at least the asparagine residue at position 3 of SEQ ID NO 51 or 52 has been mutated to an amino acid selected from the group consisting of glutamic acid, lysine, tyrosine, threonine, phenylalanine, leucine, isoleucine, tryptophan, methionine, valine, alanine, histidine and arginine.

The present invention relates to a chromatography ligand, which comprises Domain C from Staphylococcus protein A (SpA), or a functional fragment or variant thereof. The chromatography ligand presents an advantageous capability of withstanding harsh cleaning in place (CIF) conditions, and is capable of binding Fab fragments of antibodies. The ligand may be provided with a terminal coupling group, such as arginine or cysteine, to facilitate its coupling to an insoluble carrier such as beads or a membrane. The invention also relates process of using the ligand in isolation of antibodies, and to a purification protocol which may include washing steps and/or regeneration with alkali.

The present invention relates to a chromatography ligand, which comprises Domain C from Staphylococcus protein A (SpA), or a functional fragment or variant thereof. The chromatography ligand presents an advantageous capability of withstanding harsh cleaning in place (CIF) conditions, and is capable of binding Fab fragments of antibodies. The ligand may be provided with a terminal coupling group, such as arginine or cysteine, to facilitate its coupling to an insoluble carrier such as beads or a membrane. The invention also relates process of using the ligand in isolation of antibodies, and to a purification protocol which may include washing steps and/or regeneration with alkali.

The present invention provides a lectin-magnetic carrier coupling complex for separating glycosylated exosomes from a clinical sample. The lectin-magnetic carrier coupling complex comprises a magnetic carrier and lectins coupled to the outer side of the magnetic carrier. The lectin-magnetic carrier coupling complex provided by the present invention may rapidly, accurately, and automatically separate glycosylated exosomes from a clinical sample with a high separation efficiency; and the separated exosomes are intact in morphology without rupturing or cracking, may be directly used for liquid detection of glycosylated exosomes, or directly used for immunology-related detection, or directly used for nucleotide sequence detection and analysis after extracting nucleic acids from the exosomes.

The present invention provides a lectin-magnetic carrier coupling complex for separating glycosylated exosomes from a clinical sample. The lectin-magnetic carrier coupling complex comprises a magnetic carrier and lectins coupled to the outer side of the magnetic carrier. The lectin-magnetic carrier coupling complex provided by the present invention may rapidly, accurately, and automatically separate glycosylated exosomes from a clinical sample with a high separation efficiency; and the separated exosomes are intact in morphology without rupturing or cracking, may be directly used for liquid detection of glycosylated exosomes, or directly used for immunology-related detection, or directly used for nucleotide sequence detection and analysis after extracting nucleic acids from the exosomes.

Compositions useful for propagation of pluripotent stem cells are provided. The compositions comprise a polysaccharide hydrogel linked to a peptide fragment of the extracellular domain of epithelial cadherin. Methods of making the composition, and culturing pluripotent stem cells also are provided.

Compositions useful for propagation of pluripotent stem cells are provided. The compositions comprise a polysaccharide hydrogel linked to a peptide fragment of the extracellular domain of epithelial cadherin. Methods of making the composition, and culturing pluripotent stem cells also are provided.

The present invention relates to a method for modifying and purifying peptides comprising an immobilizing step, a modification step and a releasing step. In the immobilizing step, a crude linker-tagged peptide L-P is coupled to a solid support yielding an immobilized linker-tagged peptide S-L-P. Subsequently, the immobilized linker-tagged peptide S-L-P is modified with one or more organic molecules yielding an immobilized linker-tagged peptide S-L-mP. Finally, the modified peptide is released via a reduced intermediate RI. The linker molecule is a compound of formula 1, X—Tb—Va-U—Y—Z (1), which can be coupled to a purification resin via the moiety X and to a peptide via the moiety Y under the release of the leaving group Z. T is an optional spacer moiety and V is an optional electron withdrawing moiety. U is an aryl or 5- or 6-membered heteroaryl moiety bound to at least one electron withdrawing moiety V, W or E. The linker is stable under acidic conditions and releases the peptide upon addition of a reducing agent.