A Ca²‐, Mg²‐, and Zn²‐Based Dendritic Contractile Nanodevice with Two pH‐Dependent Motional Functions.

Stadler, Adrian‐Mihail; Karmazin, Lydia; Bailly, Corinne

A contractile dendritic motional device is reported where metal ions with biological importance—Ca2 (the main regulatory and signaling species of the natural muscles), Mg2 , and Zn2 —initiate two kinds of motional functions. The first motional function is the metal‐ion‐induced contraction of a linear strand into a Z‐shaped dinuclear complex, and the second one is the change of the height of Z‐shaped complexes via transmetalation. By means of the pH‐dependent counterligand tren, the two motional features of the machine can depend on alternate additions of acid and base. An optical response is associated with the conversion of the linear form (which is yellow) into the metalated Z‐shaped one (which is red).Contract and stretch: A dendrimer has been developed that contracts upon metal‐ion coordination (Ca2 , Mg2 , Zn2 ) and changes its height upon transmetalation (displacement of Ca2 by Zn2 ). These nanomechanical motions were made pH‐dependent.

Angewandte Chemie International Edition, 2015, Vol 54, Issue 48, p14570

1433-7851

Academic Journal

10.1002/anie.201506474