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The main challenge in the isolation of circulating tumor cells (CTCs) resides in their extreme rarity in blood. Here we report on the design of efficient and disposable microfluidic CTC capture devices based on the plasma functionalization of PDMS and its subsequent conjugation with the anti-epithelial-cell adhesion-molecule (EpCAM) mAb. Model studies on planar surfaces demonstrated excellent immuno-specificity of cancer-cell capture using NCI H69 small-cell lung cancer cells and SK-Br-3 breast cancer cells. Taking advantage of the transparency of the PDMS device, direct observation of the capture events on the internal 3D microstructure of the device could be achieved. At a flow rate of 16 μL min−1, an overall capture efficiency of 80 to 90% is determined in cell-spiking experiments in PBS. In accordance with direct microscopic observations, an increased flow rate (48 μL min−1) only has a minor effect (30% reduction) on cell-capture efficiency. Capture efficiency of the device using cancer cells spiked in whole blood is above 70%. The combination of soft lithography and plasma-based functionalization described in this work enables the facile fabrication of efficient and disposable CTC capture devices based on PDMS, which could facilitate the transition of this new technology into the clinical environment. [ABSTRACT FROM AUTHOR]

Parameters affecting the quality of vapour phase polymerised (VPP) PEDOT and their influence on electrochromic device performance were investigated. Specifically, the role of water during synthesis was examined and a polymerisation mechanism proposed. Paradoxically, water vapour is essential for PEDOT polymerisation, however, too high a loading leads to crystallite formation in the oxidant layer, rendering the oxidant inactive. Changes in water vapour affect the doping level of the polymer, presumably due to poor conjugation along the polymer's backbone during synthesis. The addition of a surfactant, PPG-ran-PEG, was studied using XPS. The surfactant inhibited oxidant crystal growth and slowed the rate of PEDOT polymerisation, reducing film defects and improving PEDOT conductivity. Controlling and optimising the levels of water vapour and surfactant during synthesis resulted in reproducible, high conductivity, high optical switch, PEDOT films. Finally, complementary dual-polymer electrochromic devices utilising (pre- and post-process-enhanced) VPP PEDOT and PMAS (control) were fabricated and changes in switching transmission evaluated. [ABSTRACT FROM AUTHOR]

In this communication we demonstrate that in the initial stages of deposition of ultrathin plasma polymer films, both the growth rate and the chemical composition of the films are affected by the nature of the substrate which is an important question surprisingly neglected until now. [ABSTRACT FROM AUTHOR]

Towards a robust and universal functionalization procedure with alkanethiols for gold nanorods and plasmonic nanoparticles, a straightforward two-step approach is described. [ABSTRACT FROM AUTHOR]