Counter-pressure-assisted ITP with electrokinetic injection under field-amplified conditions for bacterial analysis
Version 2 2024-06-04, 12:13Version 2 2024-06-04, 12:13
Version 1 2016-07-15, 17:21Version 1 2016-07-15, 17:21
journal contribution
posted on 2015-09-01, 00:00authored byS C Phung, Ryan Nai, M Macka, S M Powell, Rosanne GuijtRosanne Guijt, M C Breadmore
Counter-pressure was used to extend the duration of field-amplified sample injection in isotachophoresis (FASI-ITP) in order to improve the detection of bacterial cells. Using 0.51-μm negatively charged encapsulated fluorescent beads as a model, the counter-pressure, injection and separation voltages, and times were optimized. Using 6-min 8,963-Pa counter-pressure FASI-ITP injections at −12 kV followed by mobilization of the ITP band with continued injection at −6 kV, the limit of detection (LOD) for Escherichia coli was improved to 78 cells/mL, a factor of 4 when compared with FASI-ITP without counter-pressure.