Electrochemical detector with a 20 nl volume for micro-columns liquid chromatography

Capillary gap flow cell as capillary-end electrochemical detector in flow-based analysis

“…In this present study, ܸ ா has been measured experimentally, through varying gap distance and flow rate. The experimentally determined ܸ ா of 35 nL for the gap-FC is the lowest amongst those reported ܸ ா of EC detectors [18,19,22] and more importantly, the only experimentally confirmed ܸ ா to-date, which produced an EC conversion efficiency of ~11%.…”

“…4(a). In the past, the ܸ ா of alternative EC detectors have been calculated based on applying a simplified method for a known detector geometry, by multiplying electrode surface area and gap distance [18,19,22]. In this present study, ܸ ா has been measured experimentally, through varying gap distance and flow rate.…”

“…These include difficulties in miniaturisation of the system [13][14][15], frequent repolishing of the electrode [16], and low efficiency of EC conversion, typically 4-5% [17]. Additionally, there are technical issues such as a lack of experimentally determined effective cell volume (ܸ ா ) data for the different gap distance (capillary outlet-electrode) in existing EC detectors [18][19][20][21], as well as the necessity of cleaning the electrode surface during or after the experiment, and lack of EC detectors capable of being coupled with chromatographic separation platforms operating at flow rates within the nano-to millilitre per minute range [13,16,17,[19][20][21][22]. The existing mechanisms of TL-and WJ-FC in terms of layer and jet formation is reported in Hubbard et al [23], Gunasingham [13], and Patthy et al [16] respectively, which stipulate rigid construction of the EC detection FCs.…”

Microcolumn liquid chromatography: instrumentation, detection and applications

“…Mass limits of detection of 0.14 pg for adrenaline were reported. Other designs, such as wall-jet cells have been described too [ 180,181 ].…”

Analysis of cis‐platinum using a microcolumn with a β‐cyclodextrin stationary phase and electrochemical detection

“…Apparatus. The experimental work was carried out with a homemade microchromatograph (Institute of Analytical Chemistry, Bmo, Czechoslovakia) (13), which was equipped with a PMD 85-2 personal computer (Tesla, Bratislava, Czechoslovakia) and a homemade conductivity-amperomctnc detector that had a platinum electrode (14) and an inserted potential of +1.5 V. These were used for simultaneous recording of conductivity and amperometric signals (1 5). When an EMD 10 detector (Laboratory Instruments, Prague, Czechoslovakia) was used, the potential on the platinum electrode was 1.2 V (the voltage was regulated so that the basic current for the mobile phase did not exceed 50 nA).…”