from the conferences organized by TANGER Ltd.
1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) is the most used carbodiimide for conjugating biological substances containing carboxyls and amines. The use of EDC for conjugating a protein containing amines to a particle with a carboxyl group is often utilized for the preparation of modified nanoparticles, which are used for example in electrochemical immunosensing[1]. EDC is an unstable substance that undergoes hydrolysis in aqueous environments, which can lead to reduced formation of the desired conjugate. The most significant complication in the complex reaction occurs during the generation of the active intermediate O-acylisourea, which is formed in seconds in the solution. Subsequent hydrolysis and the consequent reformation of the carboxyl group prevent the reaction from progressing, resulting in no conjugate formation. Due to this limitation, there is motivation to monitor the stability of EDC in aqueous environments and to develop a simple method for rapidly determining the activity and functionality of stored EDC. We have developed a new simple precipitation method for semi-quantitative determination of the activity of EDC in aqueous solutions and tested it against the established pyridine method. The potential of our approach for rapidly assessing the active state and functionality of the EDC lies in the simplicity of its preparation and instrument independent usage.
Keywords: Bioconjugation, O-acylisourea, protein bioconjugation, 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.