If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.



Method separates intact antibody-drug conjugates

Native reversed-phase liquid chromatography allows characterization of ADCs by mass spectrometry

by Celia Henry Arnaud
February 1, 2019 | A version of this story appeared in Volume 97, Issue 5


Structure of the drug and linker from a model antibody-drug conjugate from AbbVie.
The linker and drug from a model antibody-drug conjugate from AbbVie

Antibody-drug conjugates (ADCs) are cancer therapeutics that harness the targeting abilities of monoclonal antibodies to deliver small-molecule drugs directly to tumors. Characterization of such conjugates involves determining the drug-to-antibody ratio—how many drug molecules are attached to each antibody. The standard method for determining the drug-to-antibody ratio is hydrophobic interaction chromatography, but that separation method isn’t compatible with mass-spectrometric detection. Now, a team led by Mary J. Wirth of Purdue University, working with researchers at AbbVie, reports a method called native reversed-phase liquid chromatography, which allows the characterization of intact ADCs by mass spectrometry (Anal. Chem. 2019, DOI: 10.1021/acs.analchem.8b04699). The keys to the method are using a low concentration of an MS-compatible salt, a mild organic additive, and a low-hydrophobicity stationary phase, so that ADCs can traverse the column without getting stuck or falling apart. By combining the new separation method with mass spectrometry, the researchers detected ADCs with various numbers of attached drug molecules. They demonstrated the method using a model ADC from AbbVie and a commercial ADC, brentuximab vedotin, from Seattle Genetics. A drawback of the method is that it doesn’t work well for the antibody with no drug attached.


This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.