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Small Molecule Activation

This is an intermediate step required for coupling a small molecule to a biopolymer. Some small molecules are commercially available in an activate form. For non-active molecules, we can either convert them to an active form first or let them react directly with a biopolymer using active coupling reagents.

CellMosaic uses these processes exclusively for supporting our custom Biopolymer Labeling and Biopolymer Conjugation.

Example 1: Preparation of an active ester of carboxylate (-COOH) compound for reaction with amine-containing biopolymers.

In situ activation of carboxylic acid groups using dicyclohexylcarbodiimide (DCC) and N-hydroxyl succinimide (NHS). After filtration of the byproduct dicyclohexylurea (DCU), the activated NHS-ester will be used directly for biopolymer labeling.

 NHS ester formation using DCC

Scheme 1NHS ester formation using DCC coupling


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