The invention provides novel chemical entities based on sugar alcohols. These new chemical entities are biocompatible and biodegradable. The molecules can be made in a single and pure form. The molecular weights of these molecules range from small (<1000 Da) to large (1000-120,000 Da). The sugar alcohol-based molecules can have functional groups throughout the molecule for crosslinking compounds, such as the preparation of antibody-drug conjugates, or to facilitate the delivery of therapeutic proteins, peptides, siRNA, and chemotherapeutic drugs. Also provided are new conjugate entities prepared through sugar alcohol molecules. Methods of synthesizing sugar alcohol-based molecules and conjugates are also within the scope of the invention.

A polysaccharide derivative has a partial structure represented by Formula (1) below. It is preferable that at least one of the amino acids that constitute X.sup.2 in Formula (1) below is a basic amino acid.

##STR00001##

(In the formula, X.sup.1 represents a residue obtained by removing the terminal amino group and the terminal carboxyl group from a neutral amino acid or an -aminoalkanoic acid, X.sup.2 represents a residue obtained by removing the terminal amino group and the terminal carboxyl group from a membrane-permeable peptide, X.sup.3 represents a hydroxyl group, an amino group, an alkoxyl group having 1 to 4 carbon atoms, or a benzyloxy group, a represents a number of 0 or 1, and b represents a number of from 0 to 50.)

Provided is a method for producing a short-chain peptide-immobilized carrier that maintains a secondary structure of a short-chain peptide, the method including a step of preparing an alcohol solution containing an alcohol solvent, and a short-chain peptide having a plurality of immobilizing functional groups, the short-chain peptide having a secondary structure induced in the alcohol solvent; and a step of bringing a carrier coupled with a spacer having a reactive group that reacts with the immobilizing functional group, into contact with the alcohol solution, and thereby immobilizing the short-chain peptide to the spacer.

Provided is a method for producing a short-chain peptide-immobilized carrier that maintains a secondary structure of a short-chain peptide, the method including a step of preparing an alcohol solution containing an alcohol solvent, and a short-chain peptide having a plurality of immobilizing functional groups, the short-chain peptide having a secondary structure induced in the alcohol solvent; and a step of bringing a carrier coupled with a spacer having a reactive group that reacts with the immobilizing functional group, into contact with the alcohol solution, and thereby immobilizing the short-chain peptide to the spacer.

Using a nucleic acid construct, association of a polypeptide with a sequence coding therefor and screening of a polypeptide that binds to a target substance are carried out, which nucleic acid construct comprises a 5-untranslated region and a coding region, wherein the above-mentioned coding region comprises a sequence coding for a polypeptide subjected to be displayed, a sequence coding for a first nucleic acid binding polypeptide, and a sequence coding for a second nucleic acid binding polypeptide; the above-mentioned 5-untranslated region comprises a first sequence capable of binding to a first nucleic acid binding polypeptide and a second sequence capable of binding to second nucleic acid binding polypeptide; and, when the above-mentioned nucleic acid construct is introduced in a translation system, a fusion protein translated from the coding region of the above-mentioned nucleic acid construct forms a complex with an RNA corresponding to the above-mentioned nucleic acid construct.

Using a nucleic acid construct, association of a polypeptide with a sequence coding therefor and screening of a polypeptide that binds to a target substance are carried out, which nucleic acid construct comprises a 5-untranslated region and a coding region, wherein the above-mentioned coding region comprises a sequence coding for a polypeptide subjected to be displayed, a sequence coding for a first nucleic acid binding polypeptide, and a sequence coding for a second nucleic acid binding polypeptide; the above-mentioned 5-untranslated region comprises a first sequence capable of binding to a first nucleic acid binding polypeptide and a second sequence capable of binding to second nucleic acid binding polypeptide; and, when the above-mentioned nucleic acid construct is introduced in a translation system, a fusion protein translated from the coding region of the above-mentioned nucleic acid construct forms a complex with an RNA corresponding to the above-mentioned nucleic acid construct.

The present invention provides a formulation to link protein to a solid support that comprises one or more proteins, Oligo-dT and one or more non-volatile, water-soluble protein solvents, solutes or combination thereof in an aqueous solution. Further provided is a method of attaching a protein to a surface of a substrate. The formulations provided herein are contacted onto the substrate surface, printed thereon and air dried. The substrate surface is irradiated with UV light to induce thymidine photochemical crosslinking via the thymidine moieties of the Oligo-dT.

The present invention provides a formulation to link protein to a solid support that comprises one or more proteins, Oligo-dT and one or more non-volatile, water-soluble protein solvents, solutes or combination thereof in an aqueous solution. Further provided is a method of attaching a protein to a surface of a substrate. The formulations provided herein are contacted onto the substrate surface, printed thereon and air dried. The substrate surface is irradiated with UV light to induce thymidine photochemical crosslinking via the thymidine moieties of the Oligo-dT.

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.