Mechanochemical bond scission for the activation of drugs

The liberating force of ultrasound

“…Now, writing in Nature Chemistry, Herrmann, Göstl and co-workers have now demonstrated the possibility of a new version of this last type of DDS. It exploits polymer mechanochemistry induced by ultrasound 3 .…”

“…The drug-delivery potential of polymer mechanochemistry is therefore predicated on finding general and practical means of releasing small molecules by stretching polymer chains. Herrmann, Göstl and colleagues describe three approaches that are tailored to drugs bound to polymers by covalent or non-covalent bonds 3 .…”

“…Herrmann, Göstl and colleagues describe a clever generalization of the same idea to release diverse alcohols or amines -which many pharmaceuticals are -without toxic by-products. A drug is bound to a β-carbonate disulfide moiety located near the centre-of-mass of the carrier macromolecule, which favours mechanochemical chain fracture by dissociation of the backbone S-S bond 3 (Fig. 1c).…”

“…However, as many a young child or budding sailor will attest, tying knots is difficult! This is especially true at the molecular level where only a small number of the simpler synthetic molecular knots have ever been created 3 . Now, writing in Nature Chemistry 4 , a team led by David Leigh has applied a weaving strategy to realize the formation of a seven-crossing 7 4 molecular knot possessing a non-privileged topology.…”

“…Once the metal ions are removed in each case, all that remains is the single knotted molecular chain. This pioneering work paved the way for the preparation of various entangled links and knotted molecules, such as the Hopf link (a [2]catenane), Borromean rings (three rings that are linked but removal of any one ring leaves the other two unconnected) and other trefoil knots (the simplest non-trivial knot), but it is somewhat limited in its broader scope 3 .…”