Biotin Rapid Coupling Kit

The Biotin Rapid Conjugation Kit provides a simple and fast conjugation protocol for conjugating biotin to antibodies, proteins, peptides, or other ligands containing free amino groups. The reagent reacts effectively with primary amino groups (-NH2) in a buffer solution with pH 7-9 to form stable amide bonds. Proteins, including antibodies, typically have several primary amines on the side chains of lysine (K) residues and at the N-terminus of each polypeptide, which can serve as targets for reagent labeling.

Application
(1) Rapid labeling of proteins (antibodies), etc.

Advantages
(1) High sensitivity and high labeling efficiency;
(2) Providing desalting columns and usage protocols;
(3) Providing methods for detecting labeling efficiency;
(4) This kit provides a complete set of reagents required for rapid labeling, and the reagents are easy to store.

2mg can be used to label 0.5-2mg antibodies (monoclonal antibodies, polyclonal antibodies) or other proteins:

10mg can be used to label 0.5-10mg antibodies (monoclonal antibodies, polyclonal antibodies) or other proteins:

1. Requirements for buffer and concentration of antibodies/proteins to be conjugated: Antibodies/proteins should be stored in 10mM phosphate buffer (1xPBS, pH 7.2-7.4) with a recommended concentration range of 2-4mg/mL. The buffer must not contain amino components to avoid competitive reactions with the coupling agent, which would affect the conjugation effect. Specifically, these include primary amines (such as Tris, glycine, ammonium salts, EDTA) and protein stabilizers (such as BSA, gelatin), etc. If the sample contains substances that may interfere with labeling, it is recommended to replace the buffer with PBS and concentrate to the recommended concentration.
2. For most IgG, in a cuvette with a 1cm optical path, a 1mg/mL solution has an absorbance of approximately 1.3-1.4 at 280nm. The coupling agent has no significant absorption at 280nm. Therefore, the concentration (mg/mL) of biotin-labeled antibodies can be calculated by dividing the absorbance value of the dialyzed sample at 280nm by 1.4.
3. It is recommended to store the conjugated products under refrigeration. If the final concentration of the purified antibody/protein conjugate is less than 1mg/mL, add bovine serum albumin (BSA) or other protein stabilizers to a concentration of 1-10mg/mL, which can remain stable for several months at 2-8°C. For long-term storage, the labeled solution can be aliquoted according to usage needs and stored frozen at -20°C in the dark, avoiding repeated freezing and thawing.
4. If the coupling agent solution prepared by adding the co-solvent in this kit is not fully used, it should be sealed and stored at -20°C. It can be used normally within one week. If it exceeds one week but is used within one month, the dosage should be appropriately increased; it should not be used after one month.
5. For small peptide molecules with a molecular weight less than 5KD, the amount of coupling agent solution added can be appropriately increased to improve conjugation efficiency.
6. Instructions for the desalting column (>5000 Mr) in this kit: Column volume 8.3mL, eluent 3.5mL. Gravity desalting: sample loading volume 1.0-2.5mL, desalting efficiency >98%; Centrifugal desalting: sample loading volume 1.75-2.5mL, desalting efficiency >90%.
7. If reagent D stored at 2°C -8°C has salt crystals, it is a normal phenomenon that the crystals disappear after returning to room temperature and mixing.