Hywel Morgan

..The system is characterised using a range of different sized polystyrene beads (fluorescent and non-fluorescent). Single and mixed populations of beads were measured and the data compared with a conventional flow cytometer...

..With over 130 delegates from more than 25 countries worldwide, NanoBioTech 2009 provided a diverse and invigorating forum for discussion...

..At high flow rates inertial focusing is observed; the particles flow in equal numbers through two equilibrium positions reducing the coefficient of variance (CV) in the impedance signals to negligible values...

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..The technique is demonstrated using a time-invariant passive RC network. The impedance of single biological cell flowing in a microfluidic channel is also measured, showing that MLS is an ideal method for high speed impedance analysis...

..Data are also compared with conventional flow cytometry and dynamic light scattering: the coefficient of variation (CV) of size is found to be comparable between the systems...

..The technique represents a simple method for detecting a subpopulation of cells within a heterogeneous mix. The impedance-based antibody identification method could form the basis of simple low-cost point of care diagnostic technologies...

..Our system provides a non-invasive lab-on-a-chip technology for spatially mapping the electrical properties of single cells, which would be significant and useful for diagnostic and clinical applications...

..Immunofluorescent staining of the ZO-1 tight junction protein in the untreated and treated 16HBEs was performed to verify the disruption of the tight junctions by EGTA...

..Tests with patient samples showed 95% correlation against commercial (optical/Coulter) blood analysis equipment, demonstrating the potential clinical utility of the impedance microcytometer for a point-of-care blood analysis system...

..The method is used to achieve a LOD of 20 nM with a colourimetric iron assay and a LOD of 0.22 milli-absorption units with a pH assay...

..Single channel conductance measurements of KcsA in the on-chip bilayer were recorded and these were compared to previously published data obtained with a conventional planar bilayer system...

..The data from the microfabricated flow cytometer was shown to be comparable to that of a commercial flow cytometer (BD-FACSAria)...

..5625 Hz to 500 kHz. The spectral information for each bead is obtained in approximately 1 ms. Good agreement is shown between the MLS data and both circuit simulations and conventional AC single frequency measurements...

..Scaling up the technique for use in an array platform is also straightforward, the simultaneous formation of three individually addressable BLMs being demonstrated...

..This biophysical approach gives quantitative insight into nanosphere-bilayer interactions and suggests that nanoparticle-lipid interactions alone can compromise the barrier function of the plasma membrane...

..As a result, we identify the most likely candidates to be used for future integrated device development for practical applications...

..Analysis of the 80 microm diameter trap showed that a 15.6 microm diameter latex particle could be held with a force of 23 pN at an applied voltage of 5 V peak-peak...

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..This method is suitable for incorporation into lab-on-a-chip devices and allows for buffer exchange and electrical measurements...

..The conductance of the open channel increases with increasing concentration of anionic lipid, an effect possibly due to effects of anionic lipid on the concentration of K(+) close to the membrane surface...

..The method produced BLMs suitable for single-channel recording of membrane protein activity and the technique can be extended to create programmable BLM arrays and networks...

..3 nS for CPMV, 0.38 nS for TMV, and 0.52 nS for 27 nm diameter carboxy-latex beads. Data analysis has shown that the optimal condition for separation of TMV and CPMV is a low-conductivity suspending medium - below 1 mS/m...