Figure 1: iCVD nano-adhesive bonding.
From: Non-polydimethylsiloxane devices for oxygen-free flow lithography
(a) Schematic description of the conformal iCVD nano-adhesive bonding process. The process is described in detail in the Methods Section. (b) Colour image of fully assembled channel mounted on a glass slide. The inserted schematic describes the bonding chemistry between channel interfaces. (c) Comparison of hybrid PDMS-Norland optical adhesive (NOA) and homogeneous NOA channels for solvent resistance. Using a ×20 objective indicated by the dashed red circle in the schematic, we examined the area highlighted in images. The organic solvent was seen to swell and significantly deform the channel segments constructed from PDMS after only 1 min of exposure in the hybrid device, while the homogeneous NOA device maintained its integrity even after 5 h of exposure. (d) Comparison of homogeneous PDMS and NOA channels for ultraviolet-initiated FL using mask template. PDMS channels allow for oxygen permeation, which terminates polymerization at the top and bottom faces of the device and thereby enables the creation of microparticles that can be removed via flow. In contrast, gas-impermeable NOA channels do not produce such a lubricating layer, thus creating structures fixed to the surfaces of the channel. Monomer solution consists of PEGDA 700, red acrylate 13, and PI whereas rinse solution is pure PEG 200. Scale bars, (b) 1 cm, (c) 80 μm, and (d) 100 μm.
