Antibody or Protein Exatecan Conjugation Kit with VC-PAB-Linker

Product Description

CellMosaic® has designed this kit to label any antibody or protein (≥20 kDa) with Exatecan using a valine-citruline p-aminobenzylcarbamate (VC-PAB) linker. Exatecan is a synthetic analog of Camptothecin (CPT) and exhibits antineoplastic activity by inhibiting topoisomerase 1.

Using the kit components along with a user-supplied protein or antibody, the user first converts the antibody or protein into a thiol-protein through surface amine labeling. The thiol-protein is then reacted with maleimide-activated Exatecan to generate antibody- or protein-Exatecan conjugates. The final product is then purified to remove any unreacted drug.

Kit is configured to conjugate 6.67-20 nano-mole (nmol) of one (CM11436x1) or three antibodies or proteins (CM11436x3).

If you have a smaller amount of protein, a protein with a MW below 20KDa, or other customization needs, please select the customization radio button and/or fill out the information above.

Drug Information

• Name: Mc-VC-PAB-Exatecan
• CAS number: 2504068-28-2
• Chemical formula: C₅₃H₆₀FN₉O₁₂
• MW: 1034.10
• Mechanism of action: A potent topoisomerase I inhibitor and anticancer agent. It binds to topoisomerase I (Topo I)-DNA complexes via hydrogen bonding, preventing DNA relegation and inducing DNA damage and apoptosis.
• Activities: Anti-Cancer

Requirement for Antibody or Protein

1. Preferably >90% pure by gel electrophoresis
2. Total amount: 6.67-20 nano-mole (nmol) protein content as measured by UV. 

Note: the accuracy of your antibody or protein measurement is the single most important factor in obtaining an optimized DAR or DPR of 2-4.

Key Features of this PerKit™

• Simple and efficient labeling of antibody or protein with Exatecan, minimizing toxin exposure.
• Features Cathepsin B-cleavable VC-PAB linker (Ref. Doronina et al., 2008, Bioconjugate Chem., 19, 1960-1963).
• Fast and easy preparation: 6 h preparation and less than 2 hours of hands-on time.
• All reagents and supplies included for preparation and purification
• Options to choose tailored services at CellMosaic® after conjugation

After conjugation: you can choose to send your sample to CellMosaic® for HPLC analysis and determination of the DAR.

Conjugation Chemistry

Protocol

Schematic diagram of the workflow for preparing antibody- or protein-Exatecan conjugates starting with 20 nmol of protein (volume of reagents varies if the amount of protein is less than 20 nmol).

Related Products

Hydrophobic Interaction Chromatography (HIC) Buffer Set (Product#: CM02025): For ADCs prepared via a reduced thiol of the antibody, HIC HPLC is used to calculate the DAR and the heterogeneity of the ADCs. The conjugates are separated based on hydrophobicity. Antibodies loaded with the same number of drugs (same DAR) will have similar hydrophobicity and be eluted as a single peak. CellMosaic® offers HIC buffer for our customers to use with any HIC column. The CM02025 product sheet contains all of the information and methodology needed to run an HIC HPLC analysis. If you do not have access to an HPLC facility, you can send your sample to CellMosaic® for analysis.

Size Exclusion Chromatography (SEC) HPLC Protein Standards (Product #: CM92004 and CM92005): SEC HPLC separates the conjugates by apparent molecular weight (MW) or size in aqueous solution. The larger the MW of the conjugate, the earlier it elutes. By comparing the SEC profile of unlabeled IgG and the ADC, you can estimate how much aggregation is in the ADC. CellMosaic® offers two SEC standards for our customers to use with any SEC column. The CM92004 product sheet contains all of the information and methodology you need to run an SEC HPLC analysis. If you do not have access to an HPLC facility, you can send your sample to CellMosaic® for analysis.

ADC stabilizing PBS buffer (5x) (Product #: CM02022): CM02022 contains 5x PBS buffer and other stabilizers to prevent the hydrophobic drugs from interacting with each other during storage, which would cause the ADCs to precipitate out. Stabilization buffer also helps preserve the structure of the ADCs during lyophilization. The buffer is biocompatible and can be used directly for any in vitro and in vivo studies.