Fig. 4. Positioning of functionalities within printed structures.

Illustrations (a–c) and photographs (d–f) of the spatially controlled deposition of silica cages with different functional groups and the selective binding of organic dyes. Two independent layers of cages functionalized with either thiol or amine groups are printed successively in a shifted checkerboard pattern (a, d). The pattern is then exposed to a mixture of TMR-mal and Cy5-NHS dyes (b, e), which bind selectively to the thiol and amine functionalized tiles, respectively (c, f). Between each step, the pattern was washed with methanol.