Figure 4: Formation and crystallization of peptide-based coordination networks using MLP.
From: Femtolitre chemistry assisted by microfluidic pen lithography
(a) FESEM image of a 3 × 7 droplet array in which each row comprises droplets of a mixture containing the GH ligand and one of seven metal acetates (droplet distance=25 μm). Mixture droplets within each row were created by first patterning a droplet of an aqueous solution of 1 M GH (contact time=1 s), and then delivering a solution of the corresponding metal acetate (0.3 M in 7:3 H2O/diethyleneglycol) for different contact times per row: 0.2 s (top), 0.1 s (middle) and 0.01 s (bottom). (b) Photograph showing the bulk reproduction of all screened GH-metal acetate reactions, revealing that the occurrence of crystal formation matched perfectly to the corresponding femtolitre reactions. (c,d) Representative FESEM images of crystals obtained within the femtolitre mixture of Ni(II) (c) and Cu(II) (d) with GH dipeptide. Scale bars: 2 μm. (e,f) X-ray crystal structures of the new [Ni(GH)2]·7H2O and [Cu(GH)(H2O)]·H2O.
