Cross-Linking & Modification

Download the Crosslinkers Handbook & Selection Guide            Download the Protein Labeling & Conjugation Handbook


 Cross-linking agents contain at least two reactive groups that are reactive towards numerous groups, including sulfhydryls, amines and carbohydrates, and create chemical covalent bonds between two or more molecules.  functional groups that can be targeted with cross-linking agents are primary amines, carboxyls, sulfhydryls,  carbohydrates and carboxylic acids. Protein molecules have many of these functional groups and therefore proteins and peptides can be readily conjugated using cross-linking agents. Cross-linking agents are used to study protein structure and function, to anchor proteins to solid  supports, preparation of immunogens, immunotoxins, and other conjugated protein reagents. G-Biosciences offers a variety of Double Do™ cross-linking agents, reaction specific buffers, and accessories for performing and facilitating crosslinking applications. These accessory tools simplify cross-linking reactions and will enable researchers to achieve highly efficient cross-linking reactions with minimal effort in reaction optimization, set-up, and procedure development

We offer a variety of amino acid side chain modifiers to block side chain interactions, change the charge or modify them to be more favorable for other reactions. Many denaturants, or chaotropes, are available and can disrupt water interactions resulting in the solubilization of hydrophobic proteins and peptides. Chaotropes act on proteins to unfold them and alter their three-dimensional structure. A wide selection of reagents and accessories are also available.
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N-5-Azido-2-nitrobenzyloxysuccinimide    Features Molecular Weight: 305.20 Spacer Arm (Å): 7.7 Reactive Toward: Primary Amines Membran..


Anhydrous DMF [N,N-Dimethylformamide (HCON(CH3)2)]. Suitable for cross-linking, protein modification and biotinylation reaction applications...

Optimizer Buffer™

The conjugation and modification reactions used to cross-link proteins or couple labels to proteins, such as biotin, enzymes, and fluorescent dyes, require certain conditions, including pH and chemica..


4-Vinylpyridine is used as a derivatizing reagent for free thiols such as GSH. It is used in the Glutathione colorimetric assay to remove reduced GSH, so that the oxidized Glutathione (GSSG) concentra..


ρ-Azidobenzoyl Hydrazide Features Molecular Weight: 177.19 Spacer Arm (Å): 11.9 Reactive Toward: Carbohydrates Membrane Permeable: YES Water Soluble: NO C..


APDP A sulfhydryl-reactive and photoreactive cross-linker   Features Chemical Name: N-[4-(p-Azidosalicylamido)butyl]-3’-(2’-pyridyldithio)propionamide Synonym: APDP..


ρ-Azidophenyl glyoxal monohydrate   Features Molecular Weight: 193.16 Spacer Arm (Å): 9.3 Reactive Toward: Arginines Membrane Permeable: YES Water Solubl..


Bis(β-[4-azidosalicylamido]-ethyl) disulfide   Iodinatable     Features Molecular Weight: 474.52 Spacer Arm (Å): 21.3 Reactive Toward: No..

Bolton-Hunter Reagent (SHPP)

G-Biosciences Bolton-Hunter Reagent conjugates  tyrosine-like groups to end-terminal α-amino groups or ε-amino groups of lysine to increase the number of tyrosyl groups that ca..


(Bis(2-[Succinimidooxycarbonyloxy]ethyl) sulfone   Features Molecular Weight: 436.35 Spacer Arm (Å): 13 Reactive Toward: Primary Amines Membrane Permeable: Y..

Citraconic Anhydride

Citraconic anhydride reacts with primary amines and blocks them by creating an amide linkage and a terminal carboxylate.   The linkage is stable at neutral to alkaline pH (pH >7) and at ..


Anydrous DMSO [Dimethyl sulfoxide (CH3)2SO] is offered for the solubilization of the water insoluble cross-linkers and modification reagents.     ..