That could certainly be the case when using molecules to construct microscopic devices such as medication-delivering nano-robots. It was with such applications in mind that scientists from ETH Zurich and IBM recently developed a process for building custom molecules from mix-n-match components.

The process begins with scientists choosing various microspheres made from a polymer or silica. Each one has a diameter of about one micrometer, plus they can each possess different physical qualities. These are placed side-by-side in tiny indentations, which are engraved in polymer templates. Each sphere is placed individually, allowing its position within the finished structure to be precisely dictated.