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Updated: Jan 27, 2026

Isothermal Titration Calorimetry for Measuring Macromolecule-Ligand Affinity
Published on: September 7, 2011
Protection-Group-Free Synthesis of Sequence-Defined Macromolecules via Precision λ-Orthogonal Photochemistry
Waldemar Konrad1,2, Christian Fengler1,2, Sarrah Putwa1
1Macromolecular Architectures, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT), Engesserstr. 18, 76131, Karlsruhe, Germany.
Abstract:
An advanced light-induced avenue to monodisperse sequence-defined linear macromolecules via a unique photochemical protocol is presented that does not require any protection-group chemistry. Starting from a symmetrical core unit, precision macromolecules with molecular weights up to 6257.10 g mol-1 are obtained via a two-monomer system: a monomer unit carrying a pyrene functionalized visible light responsive tetrazole and a photo-caged UV responsive diene, enabling an iterative approach for chain growth; and a monomer unit equipped with a carboxylic acid and a fumarate. Both light-induced chain growth reactions are carried out in a λ-orthogonal fashion, exciting the respective photosensitive group selectively and thus avoiding protecting chemistry. Characterization of each sequence-defined chain (size-exclusion chromatography (SEC), high-resolution electrospray ionization mass spectrometry (ESI-MS), and NMR spectroscopy), confirms the precision nature of the macromolecules.
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