Fig. 13.

Chemical patterning with temperature and RF responsive particles. (a) Two consecutive reactions in a single large unilamellar vesicle (LUV) nanoreactor. The nanoreactor was loaded with two kinds of small unilamellar vesicles (SUVs), the first kind with a phase transition temperature T_t = 23 °C and encapsulating dichlorodimethylacridinone (DDAO) phosphate (dark red), the other with T_t = 41 °C and containing fluorescein diphosphate (FDP, dark green). (Reprinted with permission from ref. 139. Copyright (2008) by John Wiley and Sons). (b–d) Schematic illustration (b) and TEM images (c, d) of the controlled-release Au-nanocages-based system. (b) On exposure to a near-infrared laser, the light is absorbed by the nanocage and converted into heat, triggering the smart polymer to collapse and thus release the pre-loaded effector. When the laser is turned off, the polymer chains will relax back to the extended conformation and terminate the release. (Reprinted with permission from ref. 141. Copyright (2009) by The Nature Publishing Group). (c) TEM images of Au nanocages for which the surface was covered by a pNIPAAm-co-pAAm copolymer with the lower critical solution temperature at 39 °C. The inset shows a magnified TEM image of the corner of such a nanocage. (Reprinted with permission from ref. 141. Copyright (2009) by The Nature Publishing Group). (d) TEM of multiple-walled Au/Ag nanoshells. (Reprinted with permission from ref. 143. Copyright (2004) by The American Chemical Society). (e–g) Optical images showing the remote controlled, spatially localized microfabrication within a capillary. Two microwires (1 and 2) were embedded within a microfabricated capillary (ca. 1 mm in diameter and 1.5 cm in length) and the capillary was aligned on top of a 2D microcoil. The microcoil was used to remotely increase the temperature of the container. Separate containers filled with pluronic and soaked with the chemical sensitizer and activator were guided into the capillary to the site of the gap within wire 1 using a magnetic stylus (e, f). The capillary was then flushed with a commercial electroless copper-plating solution; chemical reduction (bubbles of the hydrogen gas, a byproduct in the reaction, can be seen) of copper sulfate to metallic copper, occurred at the gap within microwire 1 (g). As a result copper was deposited only in the gap within wire 1 (not shown in the figure). (Reprinted with permission from ref. 145. Copyright (2007) by John Wiley and Sons).