Principle of LC-EC detection

New Flowcell How Easy?1

New Flowcell How Easy?2

SenCell33SenCellSmall, robust, easy to handleStepless variable spacing

4Antec has developed a new flow cell: the SenCell. The Sencell is small, robust and easy to handle. The 25 or 50 um polymer spacer is no longer used, in stead the new cell has a stepless variable spacing. 4SenCell - SpecificationsWorking electrode GC 2mmReference electrodeSalt Bridge - blueISAAC - greenHYREF black

5Antec has developed a new flow cell: the SenCell. The Sencell is small, robust and easy to handle. The 25 or 50 um polymer spacer is no longer used, in stead the new cell has a stepless variable spacing. 5Sensitivity wall jetFlow cell designA. thin-layerB. wall-jetC. porous flow-through

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We have explained many times that our wall jet design has a huge advantage. Thanks to this concept, the cell can be miniaturized and used in microbore LC without loosing performance.Cotrell Equation7ECD Cottrell equation ilim= 1.47 n F (Fm )1/3 (DA/b)2/3 C

ilim = C spacer thickness

A= WE area Ab = spacer thicknessC = concentrationVariable spacing more signalStepless variable spacingSmaller spacingHigher signal

8Our new Sencell has stepless variable spacing: In a turn of the hand the spacing can be set from wide to almost zero micrometer.8Spacing9

Sensitivity more signal 100um vs 12 um spacing10

The smaller the spacing, the closer the inlet is to the working electrode, the higher the signal.Sensitivity more signalStepless variable spacingSmaller spacingHigher signal11

05000100001500020000020406080100Spacing SenCell (m)S/N of 100 nM standardDA5-HTAs a result of the increased signal the signal-to-noise ratio and detection limit can be improved about 300%.SensitivityLOD50 pM DA (0.23 fmol)65 pM 5-HT (0.25 fmol)[min.]Time01234[pA]Current-24-22-20-18-16-14-12100 pMBlankDA 5-HT 100 pmole/L standards in Hac + Ringer, 5 uL injection12Here is another example of detector performance using the SenCell.

SystemALEXYS UHPLC with 10-port valveColumn Waters Acquity UPLC HSS T3 1.7 um part, 1x50 mm + prefilterMobile phase200 mM acetate buffer pH 5.5, 0.5 mM EDTA, 200 mg/L Decane Sulphonic Acid (DSA), 10% acetonitrileFlowrate200 L/minPressure469 barInjection5 L (Full loop injection)Flow cellSencell v2 (SN 00006)WE2 mm GCREFsalt bridgeSpace setting12 umEcell460 mV vs. Ag/AgClToven38 C (separation and detection)

12PressureHigher flow rate due to UHPLCSmaller spacing down to 10um

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Our SenCell is fully UHPLC compatible. New UHPLC columns have been developed with smaller particle size. According to the Van Deemter equation these columns should have improved efficiency and allow a higher flow rate.13Sencell Max PressureLeak tight ringRating: 25 bar

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High flow rates usually result in an increase in pressure over the HPLC system. Therefore the new SenCell has a 10 times higher pressure rating.14UHPLC compatibleHigh speed analysisFast responseNoise leveltime (min)00.51.0[nA]Current051015DA 5-HT 100 nmole/L standards in Hac, 5 uL injection

15Especially for UHPLC the low noise level of the new cell is crucial as traditional noise filters are useless for fast chromatography.

SystemALEXYS UHPLC with 10-port valveColumn Waters Acquity UPLC HSS T3 1.7 um part, 1x50 mm + prefilterMobile phase200 mM acetate buffer pH 5.5, 0.5 mM EDTA, 25 mg/L Decane Sulphonic Acid (DSA), 10% acetonitrileFlowrate200 L/minPressure417 barInjection5 L (Full loop injection)Flow cellSencell v2 (SN 00006)WE2 mm GCREFsalt bridgeSpace setting12 um (position 0.5)Ecell460 mV vs. Ag/AgClToven45 C (separation and detection)

15UHPLC compatibletime (min)00.51.0[nA]Current051015DA 5-HT 100 nmole/L standards in Hac, 5 uL injection

16The extremely small effective cell volume (well below 250 nL) minimizes the extra column band broadening. Even at plate numbers higher than 300.000 per meter.

SystemALEXYS UHPLC with 10-port valveColumn Waters Acquity UPLC HSS T3 1.7 um part, 1x50 mm + prefilterMobile phase200 mM acetate buffer pH 5.5, 0.5 mM EDTA, 25 mg/L Decane Sulphonic Acid (DSA), 10% acetonitrileFlowrate200 L/minPressure417 barInjection5 L (Full loop injection)Flow cellSencell v2 (SN 00006)WE2 mm GCREFsalt bridgeSpace setting12 um (position 0.5)Ecell460 mV vs. Ag/AgClToven45 C (separation and detection)

16ConclusionSenCell The most Easy to use flowcell

Wall jet performanceVariable spacing - more signal Less noise by improved fluid dynamicsUHPLC compatible

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