Testing of electrochemical efficiency of wall-jet cell FC2 as a tool for detection of electrochemically oxidisable biomarkers

In order to test the suitability of newly developed wall-jet electrochemical cells FC2 for detection of electrochemically active biomarkers, electrochemical efficiency of those cells have been characterized using [Fe (CN)₆]^3-/[Fe(CN)₆]^4- redox couple as a probe. Measurements were performed in the range of Reynolds numbers from 0.067 to 21.3 for flow rates 0.1 - 32 ml/hr. Efficiency of the cells were found to be in the range of 0.06 - 5.3 %. The dependence of efficiency E on the flow rate Q follows the equation E (%) = a x Q ^b (a = 0.855, b = - 0.746;[Q] = ml/hr) with R = 0,999. The difference between the three cells can be characterized by SD of a and b (8.2 % and 5.2 %, respectively). The dependence of current I (nA) on the flow rate Q follows the same equation I(nA) = a · Q^b with a = 2294 and b = 0,255 (SD = 8.2 % and 14.7 % for a and b, respectively). FC2 cell with wall-jet hydrodynamics provides reproducible electrochemical measurements with well-defined efficiency and current flow dependence.