Skip to main content
European Commission logo print header

Self-assembly of Helical Functional Nanomaterials

Article Category

Article available in the following languages:

Novel polymers enhance MRI scans

EU-funded researchers developed novel self-assembled supramolecular polymers that should enhance the scans from magnetic resonance imaging (MRI).

Industrial Technologies icon Industrial Technologies

Magnetic resonance imaging (MRI) that enables viewing thin ‘slices’ of tissue has enabled non-intrusive diagnoses of many diseases based on structural abnormalities. Contrast agents such as paramagnetic Gadolinium(III), or Gd(III), used to enhance the differences among different tissue types have played a critical role in the successful application of MRI. The development of supramolecular complexes based on self-assembled Gd(III) chelating molecular units could combine the benefits of both low and high molecular weight derivatives. While self-assembly of linear molecules into spherical or cylindrical structures has been extensively studied, its extension to self-assembly of one-dimensional (1D) ordered arrays such as rod-like superpolymers is rare. Construction of water-compatible, self-assembled nano-sized objects employing exquisite control of size, shape and functionalisation of features is of critical importance to the development of novel nanomaterials for MRI contrast agents. European researchers initiated the ‘Self-assembly of helical functional nanomaterials’ (Sahnmat) project to develop techniques to control the growth of aqueous 1D supramolecular polymers with potential applications in electronics, sensing and regenerative medicine. Scientists turned to nature and the self-assembly of biological systems such as the phospholipid bilayer cell membrane, dictated by hydrophilic (relatively charged or water ‘loving’) and hydrophobic (non-polar or neutral, water ‘fearing’) interactions among molecules. The self-assembling molecular unit was based on a symmetrical core (C3 symmetrical benzene-1,3,5-tricarboxamide) that directed 1D self-assembly into helices (like stretched springs) consisting of stacks of disk-shaped molecules. This structure was modified to create a hydrophobic pocket in the core. Changing the balance of non-covalent attractive forces within the hydrophobic core and electrostatic repulsive forces on the hydrophilic rim enabled a switch from elongated, rod-like assemblies to small discrete structures. Further spectroscopic experiments enabled correlation of growth mechanisms with the morphology of the structures produced. Sahnmat scientists demonstrated a unique method of directed self-assembly in water of supramolecular polymers governed by interactions among electrically charged particles. The polymers, promising potential building blocks of MRI contrast agents, could have important impact on the future of molecular imaging.

Discover other articles in the same domain of application